Technology is getting better daily as the digital market expands into all avenues of convenience. So is it possible that guitar tube amplifiers will take a final bow like the tube radio? Can solid state emulation replace all the nuances created by tube amplifiers? Let’s discuss!

On an expedition through the gear smorgasbord the tube amp might be the last piece of the equation to be replaced. Recent years have brought a leap forward with solid state amps, amp software, pedals and cabinet simulators flooding the
market. I am a believer in a few of these items in my own studio. Cabinet simulators play a larger role in my recordings than the others. I have been impressed by the offerings of current manufactures in the pedals, solid state amps and software emulation available as well. Admittedly a lot of guitar parts I record now days utilize Two Notes technology within their Wall of Sound plug in.

I do not necessarily need a huge mic locker or guitar cabinet warehouse with different size cabinets, speaker choices and ohm capacities. This advance made by Two Notes has minimized the amount of setup and has exponentially increased time to experiment more efficiently while also not blowing up my ears in the process. Of course I still own multiple cabinets, with multiple speakers and with different ohms—it’s just a different feel to the music. The more tools the better in my opinion—after all, every song is different and requires its own stamp on the musical landscape.

Sophisticated pedal such as the Orange Bax, (which features on-board EQ, Gain and a cabinet sim—yes, all this from just a pedal!) can offer originality to your playing. Insert that in your chain and turn your silverface into an Orange! If pedals can push the limits, what can be done in a larger format head or combo amps? The differences between a tube amp and a solid state are still noticeable overall and it might just come down to the irregularities of tube performance that create those beautiful noises with all that power running through them.

As far as tube amps go, my tube locker contains all sorts of letters and numbers each with their own sound palette. For this reason I believe there is more fun to be had with a tube amp. Some tubes can really open up the sound or dull it beyond belief. The ability to change from an EL34 British type power section to a more American style 6L6 is a good time in experimentation. At other points, a little something different is needed and altering the power section is a great feature on many amps that provides a ‘new’ amp in your arsenal.

Then there is the ‘fun’ factor of the preamp section—overall preamp, each channel, phase inverters and reverb! Any where from 2-8 tubes can be swapped for different shade in the sound. For additional options change the speaker or the cabinet that is part of the rig and boom, new sounds. There is a lot of interaction that takes place between you, guitar, cab and the tube amp. Playful feedback is tossed into the mix and can be summoned when provoked.

Unfortunately all of that excitement begins to dim when a tube starts glowing a different color or suddenly fades out like a dying star. As we all know, there are legit worries with owning tube amps. Maintenance for one ranks higher than others. In some cases, opening them up should be left to the professionals. The internal guts of these wonderful boxes are delicate from the wiring, capacitors, transformers and, of course, the tubes. This can lead to an expensive effort to find what works in an amp or in the instance when a tube has lit for the last time. When a tube wears
out I generally start to question if I like the amp anymore and that is a good way to identify if a change is required. If you own a tube amp I would highly recommend Orange’s VT1000 for your tube testing needs. Alas, problems do not stop there. Weather impacts performance, moving them around without harming the tubes is a worry, what if a fuse fails, is a backup needed to gig with?–you get the idea.

On the other side of the musical rainbow is the solid state amp. Worries are gone with solid state, right? Sure, there could be harm bestowed moving the amp from practice space to gig but no tubes to fail, no fuses to worry about. At 8 o’clock it sounds the same at 3 o’clock on the master volume. No breakup changes to worry about when cranking to get more volume over your drummer. Life is good.

Another improvement in our toolbox is modelling software. Imagine having every amp you have ever dreamed about within your computer or a small box that takes up less space than one amp head available to you at all times. I’m interested! The advantages are definitely tempting. All the back breaking amps, cabs and combos can stay at home. Simply show up with your computer or modelling amp and go direct into the soundboard. Which almost seems like blasphemy to a stage setup though your back will thank you, perhaps a cheaper alternative in the long run and certainly less dangerous in upkeep. The con list extends more to the tone side as there is less chances to experiment with tone changes due to lack of tubes and reliance on pedals almost becomes mandatory. Pedal dependency is a personal choice driven by what style you are playing. I
adore the edge of breakup tone, pushing the power section to break is glorious. With a solid state amp, that line in the sand no longer exists unless it is built to simulate that classic tone.

The edges can become blurred once the guitars have been recorded. Which track is solid state? Which track is an emulator? Which track is tube? I have mixed solid state and tube amps on a few occasions and I still hear the difference between them, even if they do sound good together, they are still not entirely equal. The difference becomes clearer when you start mixing all those sounds together. Certain sections stand out a little more than others and you might not be able to tell which is which but the alteration is heard.

I have been impressed by many different solid state heads and I had the pleasure of playing the Crush series as well as some of its competitors lately. Certain software packs sound pretty good but not enough that I say—that’s it, I am buying it! Sorry UAD!
I am not putting down the solid state crowd, I just don’t believe we are there…yet. Is the tube amp safe? I believe it is but in another 10 years the tube purist in me might be shaking in my boots. For me there is just too much interaction between that tube amp and guitar that could be missed with solid state.

Obviously I am not solid on the idea of bidding goodbye to my tube amp arsenal but I have been swayed on other advances as stated. The time is coming and it is close, when the tube amp might be a tool of the past; or at least one where we self-proclaimed purists are the only believers requesting to be buried ensconced with our tubes.


A pedalboard’s primary function is to provide a home for your beloved pedal collection as well as making life a little easier out there on the road, but they are not solely the domain of effects pedals per se. Pedalboards can also provide a haven for other guitar-orientated bits and pieces; some of which might not be that familiar to some of us. So with that in mind what else might we find lurking in the dark corners of a pedalboard other than effects pedals…

Amp Controller
The footswitch for your amp (if it has one) is probably the most common inhabitant of a pedalboard after effects pedals.

They come in all shapes and sizes…

They come in all shapes and sizes…


Power Supply
If you’re running pedals, you’re probably going to need power. What format it will take on your board (if it’s even on your board at all) is up to you. Besides batteries, the choices are power-banks such as those by T-Rex or Voodoo Labs, something like Pedaltrain’s Volto or direct from the mains.

There’s something to suit all tastes…

There’s something to suit all tastes…

Wireless System
If you like to go jumping about the stage like you’re possessed by some kind of rock demon (we like to think that these really do exist), a wireless system may be a necessity. They’ve evolved over the years and where older versions were slightly cumbersome (more often than not they were designed to be part of a rack-mounted setup) some of the newer breed such as Line 6’s Relay Series or Shure’s GLXD have been designed to be pedalboard friendly.



If you’re a pedal board junky then you’re probably aware of these already. They give your signal a little more oomph to make sure it gets through all those pedals and all that extra cable without losing any of its sparkle. Several manufacturers produce bespoke buffers; Boss on the other hand include them in the majority of their pedals as standard.


Custom Audio Electronic’s MC406 and JHS’ Little Black Buffer…

Loop / Bypass Pedal
It could be argued that these fall into the category of effects pedals but strictly speaking a loop / bypass pedal such as One Control’s Crocodile Tail or MXR’s Loop Box are more utility pedals rather than effects.
Loop pedals (not the recording kind to avoid any confusion) allow any pedals contained within the loop(s) of the unit to be simultaneously taken out of your signal chain with just a single stomp (so no more tap dancing). If it’s a programmable unit you can assign particular loops containing certain effects to specific footswitches.

As complicated…or as simple as you want…

As complicated…or as simple as you want…

A/B/Y Switch
Similar to loop / bypass pedals in that they allow you to re-divert your signal, AB pedals allow you to break your signal chain into 2 parts (or more sometimes) and use either one side or the other…or both if there’s a ‘Y’ involved. Why would you want to do this? Well if you use more than one guitar rather than unplugging every time you swap you simply plug both into the AB box and select either with the stomp of a switch. Alternatively you may want to run more than one amp. Simply connect an amp to either output of the AB box and you’re good to go *.

* If you’re running more than one amp please remember that you need a speaker load for each amp; don’t plug 2 amps into 1 speaker cab because things will go bang (and not in a good way).

A, B or indeed Y…

A, B or indeed Y…

DI Box
Lots of pros run a DI (Direct Input) box straight from their boards to get a signal straight to the sound desk. This clever bit of kit performs various tasks (such as level and impedance matching) to ensure that your line signal is compatible with the desk.

To DI or not to DI; that is the question…

To DI or not to DI; that is the question…

Not much to say about these really; every pedalboard should come with one as standard.

Turn on, tune in and rock out…

Turn on, tune in and rock out…

Noise Gate
These clever little boxes keep hisses, squeals and any other unwanted sounds to a minimum by controlling the volume (amplitude) of the signal. In simple terms they allow a signal through only when it is above a set level i.e. the gate is ‘open’. When the signal falls below this level no signal is allowed through i.e. the gate is ‘closed’.

Silence is golden…

Silence is golden…

If you’re into pedalboards then this is all probably common knowledge. But if you’re not, some of this stuff may be new to you and so the next time you see a board and think to yourself what is that little (or not so little) box you now might have the answer. Pedalboards can be home to lots of things such as mic stands, pick tins and slide holders, so when it comes to what a pedalboard is used for the world is quite literally at your feet.

By Guest Blogger Darren Carless

Previous blog articles have briefly looked at the types of effects that are available to modern guitarists, what you need to be thinking about when taking your first steps into the world of pedalboards, and the enigma that is the effects loop.

With those previous editions in mind, this article looks at arranging your selection of effects in order to optimise their performance and get them doing what you want them to. The way in which your effects are arranged has a massive impact on your overall sound. This is because they will all react differently depending on where they are placed in the chain due to the signal that is fed into them (i.e. pure guitar signal or signal from another effect).

Deciding upon your setup is a big decision…so how do you know which way is right and which is wrong? Well as you’ve probably come to expect by now (as with everything else when it comes to your setup) there is no right way or wrong way to chain your pedals together…it’s simply all about finding out what’s best for you!

The general consensus on the proper arrangement of effects is as follows…

  1. Dynamic effects (e.g. compressors)
  2. EQ’s and filters (e.g. wah-wah)
  3. Drive effects (e.g. overdrive, distortion and fuzz)
  4. Modulation effects (e.g. chorus, phasers and flangers)
  5. Delays / Echoes (although more often than not these can be found in the effects loop of the amp)
  6. Reverbs (also usually found in the effects loop of the amp

This arrangement means that the raw signal (i.e. from your guitar) is straightened out and refined first, before being distorted and boosted and then made to wobble. Next echo is added to the modified signal and finally it is reverberated.

Here’s a few suggested setups and what you can expect from them…




This follows the order above and is a good place to start if you’re trying to get to grips with arranging your effects. This is considered to be the classic setup.




This is a common variation on the standard setup. Here the wah-wah and the modulation pedal are swapped around. This arrangement will make the wah-wah stand out a lot more. When using older (more often than not analogue) modulation pedals it can be worth experimenting and placing them before your drive pedals, as sometimes they can sound a bit mushy when placed after.




If your amp has an effects loop it’s always worthwhile trying your delays and reverbs in it (modulation pedals are often placed in effects loops too). This setup will usually mean that your delay and reverb will sound more prominent. It will also simplify the signal going into the front of your amp.




Compressors should always be placed at the start of your chain, as their job is to even out the dynamics of the signal. Putting them later in the chain will only amplify any noise built up before them. You could also try this arrangement with a wah-wah positioned between the compressor and modulation pedal.

So there you go…as easy as that. If after reading this you’re sat there thinking it all looks and sounds very complicated (although it can be if you want it to be) don’t be put off as in reality it’s very simple…you get a pedal and plug it in, then you add another to it, then you swap them around and then add others and change the order until you find the sound that you’re after. Some decisions will be made for you (e.g. if your amp doesn’t have an effects loop you’ll have no choice but to put everything into the front of your amp) but for the most part it’ll be down to your personal preferences. Remember when it comes to effects experimentation is the key so get your hands on some and get stuck in!

It’s quite evident that the effects loop is still greeted with mixed reviews even though it’s been with us for quite some time now and is a very common feature on many guitar and bass amplifiers such as Orange’s TH30 and OR15. In order to gain an understanding as to whether the effects loop is a friend, a foe or simply something that is misunderstood, let’s start at the beginning and get to grips with the history and basics of the effects loop.

The effects loop first appeared in the 1970’s but it was the 80’s that really saw it come to prominence. Why the 80’s? Well…prior to that decade amplifiers only had clean channels and any effects used (more often than not tremolo and reverb) were usually built into the amp. When overdrive and distortion became popular amps began sporting a designated ‘overdrive’ channel and it was quickly discovered that putting effects into the front of the amp, as had been done previously, didn’t necessarily create the desired sounds. The effects loop was created in response to this problem and allowed the placing of effects after the preamp but before the power amp.

Effects loops are usually found on the rear side of the amplifier (not always though) and are normally identified as ‘Send’ i.e. Output and ‘Return’ i.e. Input. They tend to come in one of two varieties: a ‘series’ loop (all of the signal is passed through the effects in the loop) or a ‘parallel’ loop (part of the signal passes through only the amp, while the other part passes through the effects loop and is then mixed back together with the clean signal).

Untitled (1)

So now that we have a basic understanding of what the loop is and does, why would you want to use it? There are a number of benefits to be gained when using an effects loop. The biggest advantage is that effects placed in the loop tend to sound clearer and more pronounced. Another bonus is that by placing effects in the loop there is less likelihood of any signal loss due to an impedance mismatch, which can occur when using rack-mounted or pedal-based effects (to help with this many effects loops have a level/gain control).

Using the effects loop does have its negatives as well. You do need to run extra cables in order to use it (like we don’t already have enough of those). There is also the fact that the extra cable length for the loop can actually change your signal (it may weaken it or cause tone loss).

So if you decide to use the loop, what effects should you put in it? The general consensus is that time based effects (e.g. delay, flange, chorus etc) sound better in the effects loop whilst dirt effects (e.g. overdrive and distortion) and compressors work best in front of the amp. This, of course, is all subjective and there is (within reason) no right or wrong way to set up your equipment. It is worth considering what you are trying to achieve when using an effects loop however. Take a booster pedal for example, which works in either position. But a booster in front of the amp will only drive the preamp harder, and if you’re already rocking out a load of gain on the amp, you won’t really notice much difference. However, if you place it in the loop, a booster will give the whole signal a shot before it reaches the power amp and should increase the overall volume.

As an avid user of the effects loop I’ve read lots of material on the way they should be used and what benefits they can bring to your setup. This led me to my decision to set up my gear with the loop in mind. The other guitarist in my band can’t even begin to get his head around the need for extra leads, never mind the concept of the loop or how it works. As mentioned above there is no correct method to setting up your gear and, just like the choice of guitar, amplifier and effects pedals are all down to personal taste, whether or not you choose to use the effects loop is also a personal preference. That said the next time you have a look around the back of your amp and see those two sockets just bear in mind what they could actually do for you. They may open a whole new world of extra tonal options and you may find out that the effects loop is something that should be explored and not feared.

Guest Blogger: Darren Carless

How did you come up with the circuit?
It was during a night of terror. A lizard appeared and looked me right in the eyes. In his deep marble eyes I saw an amp next to an A4 pad of paper. He was a tiny terror. [Adrian wanted to design an amp that could “fit on an A4 pad of paper.”]

What’s the ethos behind the circuit?
Everybody wants to play a show and have a couple of beers without having to drive. The Tiny Terror allows you to do just that because you can easily carry it. Call up one of the other bands on the bill and ask if it’s cool to borrow their 4×12. Play the show with volume on 10, tone on 10, gain around 12 to 2 o’clock and get right into the output tubes. The guy you borrowed the 4×12 from has a 100 watt marshall with the pre-amp on 9 and the volume on 2 sounding like a dentist. Your cranked TT geetar sound is SOOO good that you attract the attention of some of the laydeez :) You wind up going to a party with them, still carrying your Tiny Terror and your geetar and your night suddenly gets even better :)

How does the circuit work?
Simply, it’s this, the first gang of the gain pot increases the gain of the first stage. The second gang of the gain pot increases the impedance of the second stage. This results in the signal pushing into the output tubes evenly all the way up. The phase inverters in a lot of amps is complete snollygoster. The one in the TT is perfect. The EL84s have the best distortion sound, the cathode biasing gives you more smerge swomp. This results in the pancakes being thick in treacle [molasses]. Thicker than the dude you borrowed the 4×12 off of.

Technical Director Adrian Emsley (Left) with Dr. Damon "I Wear Bike Shorts In The Winter" McCartney (Right)

Technical Director Adrian Emsley (Left) with
Dr. Damon “I Wear Bike Shorts In The Winter” McCartney (Right)

Interview by Dr. Damon McCartney

As Senior Amp Tech for Orange USA I get a lot of questions regarding which Overdrive/Distortion pedals work best with our amps. As you may well know, our product line is quite diverse, yet each amp we make has a certain common characteristic midrange bark that I lovingly call “Orange Punch”.



While this tonal trait is part of what makes our amps special, it can be a challenge to find pedals that will work with  the amps natural tone and compliment it rather than bury it or fight it. Here are a few of my favorites that I have found to work especially well with all of our amps:


1) Fulltone OCD:  I cannot overstate how great this pedal sounds! From a subtle boost, to a natural overdrive, to full on high gain, it does it all and it does it without killing the natural sound of our amps. My favorite way to run it is with the drive between 10-11 o’clock and the volume pegged to goose the front end of my Retro 50 and make it cry for mercy. I also like to use it in the studio with the clean channel of our amps as a sort of third “in between” sound. The pedal has two modes of operation, high peak and low peak. High peak can give a little more bass and drive, as well as some extra upper midrange if you need to cut through a dense mix. Low peak is your sound only more, without tonal change. A great trick with this pedal is to run it at 18V, which gives it more headroom and a truly “amp-like” feel that responds to your pick attack and volume control just as our amps do naturally. I’ve tried just about every drive pedal out there and I always come back to this. It works, it’s bulletproof, and it’s relatively inexpensive given the quality and flexibility.



2) Maxon OD808:  This one is for Metal, plain and simple! I know what you are saying, “but that’s just a tubescreamer knock-off for the SRV clones out there” and you would be somewhat right. However the Maxon OD-808 has a couple of small circuit tweaks done to the original tube screamer circuit that sets this one apart from your standard TS-9 and TS-808. This pedal does have an EQ coloration, it shaves of a little bit of the sub low frequencies, and adds a nice midrange coloration and compression to the tone. When you combine that with our high gain amp channels, it tightens them up for some extra low-string clarity while also adding some weight to the high notes courtesy of that nice midrange. A ton of your favorite metal players use this pedal with high gain amps for this EQ curve, as opposed to adding a ton of gain from the pedal. The typical settings are drive at off to 10 o’clock with the blend all the way up and the tone set to taste. If you love metal give this one a shot.


3) Way Huge Swollen Pickle: This one is for the adventurous amongst you! It is not subtle, it can make your amp sound like an army of mosquitos or elephants depending on how you set it up. There is also some old school late 60’s/early 70’s fuzzed out goodness in there, think early Black Sabbath, Neil young, T. Rex etc. If you are like me and love the first two Smashing Pumpkins albums, then you need this pedal. It does have a lot of parameters, and can be somewhat of a challenge to dial in perfectly, but when you do you will be rewarded with some of the sickest fuzz tones out there.


4) Pigtronix Class A Boost: If your tastes run more towards the cleaner side of the spectrum, or you need something to just boost the volume of your amp, give this awesome pedal a try. When set up in front of your amp it gives you 30db of pure high headroom volume boost. It is very tonally neutral, giving you your pure guitar to amp tone while just making it LOUD!! It is also one of the only boost pedals designed to work at line levels. This makes it possible to use in the FX loop of our amps for a volume boost for solos. It’s also bonehead easy to use, a single volume control is all you get, set it and forget it!

I recommend you check out some YouTube clips of these pedals, but ultimately the best thing to do is to go to a music store and try them yourself. All of them work great with our amps, are reasonably priced, gig tough, and the manufacturers stand behind their products and offer tremendous support.

Until next time, keep it loud, keep it proud!

Jon Bailey

Senior Amp Tech


Read what booking agent, manager, and promoter, George Gargan, has to say about his experience with Orange Terror Bass amps and cabs…

“Backline Without The Backache”

By George Gargan

I started to put on gigs in London back in 2006 under the name of Damnably. I have a particular taste in music and the bands I love would not always play the UK so I got into booking tours and then releasing records. All the while I followed super DIY principles I’d lifted from the hardcore scene.

Bands coming over from Japan, Canada, USA or Europe would request backline because bringing over amps and drums is just not viable (due to cost) unless you are a pretty big band.

So I checked out the London backline hire places and found them to be prohibitively expensive. For example, in 2007 I needed a drum kit and bass amp for a Thee More Shallows/Lone Ladygig at The Social W1. The cheapest drum kit hire I could find back then was £300 a day plus deposit, delivery and VAT.

Shocked, I checked out new drum kits online and bought an Olympus drum kit and Behringer bass combo for £300 in total. I used them for that gig, then sold them a little while later making back the outlay. That gig was a sell out and the bands were very happy with the gear, plus I was able to cover their meals, cab fare, and paid them quite well.

Our record label started to get more acts so we decided to help them by investing in a decent touring drum kit, drum hardware, guitar amps and a bass amp. Any act coming over could happily use the gear on tour for free. For bass we chose the Orange Tiny Terror Bass Head and the Isobaric Sp212 cab.


Ihave to say our F****r Twin [name deleted to protect the innocent] has had to be repaired 3 times to the tune of £400, but our Canopus drum kit and Pearl hardware have not had any issues and the Orange mini bass stack has been amazing!

Size really isn’t everything. Each time we let a band use the Terror Bass they are skeptical of the power the little head and cab can muster, but without exception, after every show the bassist has loved it and been impressed by the clarity of tone and sheer volume power. This has included Shonen Knife, Bitch Magnet, Bored Spies, American Werewolf Academy, Bottomless Pit, Shannon Wright plus London bands: Former Utopia, smallgang, Crumbling Ghost and Slowgun,  and scores of support acts that have used the backline on UK/Ireland/European tours to save bringing their own gear to a venue.

Shonen Knife performing with the Terror Bass and SP212

Shonen Knife performing with the Terror Bass and SP212

The bands we work with are usually pretty heavy post punk and create some very distorted, dissonant hard rock sounds. But the SP212 has handled everything we’ve thrown at it with a lot of headroom to spare thanks to the isobaric design of the cab.

This little bundle has survived a lot of tours, saved our bands a fortune on hire all over Europe, seen massive festivals and tiny venues, and has always fit in superbly. It’s lightweight and easy to carry and takes up hardly any space in a tour bus yet still delivers the sort of power an old 8×10 stack would (and anyone who has been on tour will know that a 8×10 Bass cab is a recipe for back ache!). So our bands and backs praise this little Orange Stack.

Damnably records

Welcome to another edition of Getting Technical and the second part of our self help guide to diagnosing problematic valves in your amplifier. Whilst valves are undeniably awesome, they are fragile little things put under a great deal of stress, and it is an unfortunate truth that they can fail at any time – a kind of ‘occupational hazard’, if you like, that comes with ownership of a quality valve amplifier. Being prepared for this eventuality is something we’re keen to promote here at Orange Amplifiers so if you missed the previous entry on output valves you can catch up here. This month sees the turn of the preamp valve.


Preamp Valves 

There are two types of preamp valve found in Orange amps which are referred to by different names depending on which side of the Pond you happen to be sitting. Unlike output valves, preamp valves can be swapped out individually if necessary, making them a relatively cheap fix if they go bad. Nor do preamp valves need any form of biasing and generally speaking will last longer and require replacement less often than your output valves, so developing a basic understanding of them can save both time and money when it comes to changing them.

  • 12AX7 or Ecc83: These are responsible for shaping your tone and the amp’s various gain stages. These valves are known as ‘Dual Triode’ valves which have two halves, each capable of performing an independent function.

Orange valve amps have at least one 12AX7/Ecc83 contributing between two and four stages of gain. As a general rule the higher the number of gain stages, the more filth is available! These valves are also used as ‘phase inverters’ which split the audio signal before it reaches the amp’s output section. Whilst most Orange models use just one phase inverter, our Dual Terror and AD30 twin channel amps have one per channel.

  • 12AT7 or Ecc81: These feature in any Orange amp with an either effects loop and/or spring reverb. Also a Dual Triode type valve, these are responsible for ‘buffering’ the guitar’s signal to ensure transparency and maintain tonal integrity, something we are very proud of here at Orange.

How will I know when I have a preamp valve problem?

In the previous article I mentioned that most ‘noise’ issues are normally due to faulty or worn preamp valves. Whilst a little hissing on higher gain settings is perfectly normal, these noises often take the form of excessive hiss and/or hum at moderate gain and volume settings. You may also experience crackling or intermittent sputtering/cutting out. The worst case scenario, although rare, is that a completely failed preamp valve will result in an open circuit and the amp will produce no output at all! Any of these problems may only occur on one channel (if your amp is a twin channel model) and this is a common sign of a faulty preamp valve. We’ll explore this in further detail in the two examples at the end of this article.

A simple way to help decide whether a preamp valve is responsible for a noise issue is by experimenting with the Gain and overall Master Volume controls. Turn the Gain control clockwise to between 12 and 3 o’clock and slowly reduce the Volume. If the noises continue with the Volume turned to zero, it is most probably an output valve problem. If the noises go away after turning the Volume down, it is likely to be a preamp valve.

However not all preamp problems will be of a noisy nature. If you are lucky enough to own a Rockerverb or Thunderverb but the reverb isn’t functioning as it should, you may find that one of the 12AT7/Ecc81 valves is faulty and this should be replaced.

What are microphonic valves?

As the name suggests, this is when a valve starts behaving like a microphone being held too close to a speaker. They are characterised by very unpleasant high pitched squealing and uncontrollable feedback which continues even when the guitar’s volume control is turned all the way down. Microphony can be caused by a number of things but vibration is usually the culprit. For this reason, combo amplifiers can be a little more susceptible to microphonic valves where the speaker and the valves are in closer proximity than a separate ‘head and cab’ rig.

If your amp is guilty of any of these noises you can say with a good degree of certainty that at least one of preamp valves will need replacing. Output valves can also become microphonic, although this is less common.

How do I know which preamp valve is bad?

The simplest way to troubleshoot a faulty preamp valve (unless you have one our DIVO VT1000s to hand) is good, old fashioned, trial and error! However, you can often save time and isolate a problem by using the valve position diagram for your model. These are available to download from our website on your amp’s product page.

These diagrams describe each valve’s type and their role in the amplifier. They can be especially useful if you own a twin channel amp, like the Orange TH30 in the example below, although you can of course apply the same logic to any model. If your amp is a single channel model, this normally means fewer valves to go through!

Occasionally, a bad phase inverter or FX loop valve can cause the whole amplifier to sound weak and lifeless. Whilst this is normally associated with worn output valves, it’s often worth replacing these preamp valves first. Preamp valves are normally cheaper to buy and can be replaced individually, unlike output valves. Even if it turns out to be the output valves causing the problem, you will at least have a couple of spare preamp valves to hand in future!

The ‘Tap’ Test

Noise problems, particularly microphonic preamp valves can often be identified with a simple ‘tap test’. Exercise caution if attempting this as the valves will be hot when in use. With the amp switched off, remove the metal screening cans shrouding the preamp valves by carefully pushing down and applying a quarter turn. The screening cans are there to reduce outside electromagnetic and radio noise so a slight increase in noise or buzzing may be normal when removed. Then, with the amp switched on, softly tap on the glass with the end of a pencil or chopstick. 

Some minor metallic noise is absolutely normal when a preamp valve is tapped in this way, and a valve in the early stage of the circuit – for example Gain Stage 1&2 – will always appear slightly noisier as anything here is amplified by the valves which follow it (imagine it as a snowball effect). However, if the sound changes, gets worse or begins to ‘self-oscillate’ (makes a strange synth-like note all by itself) the valve causing it should be replaced.

Screening Cans removed to reveal the preamp valves on an Orange Dual Terror

Screening Cans removed to reveal the preamp valves on an Orange Dual Terror

Using a Valve Positions Diagram to isolate faulty valves: An example.

Let’s assume here on this TH30 that there is a problem with the Dirty channel (e.g. unusual noises), which then disappears when switching back to the Clean channel. It might also be that we get no sound at all on the Dirty Channel, but the Clean channel is working normally. In this case we can save ourselves a headache by narrowing the problem down to just one or two preamp valves on the Dirty channel.



Whilst the output valves are in use on both Clean and Dirty channels, some of the preamp valves are assigned to a particular channel. Preamp valves which are not labelled either way are shared by both channels.

Because our Clean channel is sounding as it should, we can ignore ‘Clean Channel Stage 1&2’ straight away. We can also see that in the TH30 the FX loop and PI (Phase Inverter) positions are shared by both channels, so we can ignore these by the same process of elimination. If either the FX loop or PI was at fault, the problem would appear on both channels.

This leaves us with either ‘Dirty Channel Stage 1&2′ and/or ‘Dirty Channel Stage 3&4′:

  1. Switch off the amplifier and replace the Dirty Channel Stage 1&2 valve with a known ‘good’ spare 12AX7.
  2. Switch the amp back on. If the issue has now gone, the problem valve has been identified.
  3. If it still occurs, we can assume that the valve that has just been removed is actually OK, and can be returned to its original position.
  4. Repeat the process with the second Dirty Channel 12AX7 valve, and in most cases the issue should be resolved.

It is of course possible that both Dirty channel valves are at fault, and whilst this is unlikely, never rule out this possibility. For this reason, it is advisable to keep a couple of spare 12AX7 valves in your kit, especially if you are a gigging musician.

Another Example…

 This time, we’re getting some nasty feedback/squealing on both channels of our TH30. As this type of issue is likely to be a preamp valve problem, we can draw our attention to the preamp valves shared by both channels. In this case, these are the 12AX7 in the Phase Inverter position, and the 12AT7 driving the FX loop.

Remember, even if no effects pedals are connected in the FX loop, the valve which drives this part of the circuit is always in use, and this is true for all Orange models with this feature. You can use the ‘Tap Test’ here to help diagnose the fault.

Some general preamp valve tips:

  • Problems with noise are usually preamp valve related.
  •  Only faulty or worn preamp valves need to be replaced. A full preamp re-valve will never do any harm, though!
  •  In the case of twin channel amp, try to narrow the problem down to a specific channel if possible.
  •  Use the valve position diagram to help isolate the fault. These are available at 
  • The 12AT7 valves driving the spring reverb and effects loops in all Orange models are always part of the amp’s circuit so do not disregard these altogether, even if the reverb or effects loop are not in use.
  •  Keep at least one spare 12AX7 valve handy, and at least one 12AT7 if your amp has an effects loop or spring reverb. Valves are available to purchase directly from our online shop:
  • Always replace a preamp valve with a like-for-like type, i.e. do not use a 12AT7 in place of a 12AX7.
  • A failed preamp valve will never cause the amp’s HT fuse to blow. If this is the case, it is almost certainly an output valve failure

         Remember: Preamp valves do not require biasing!

Thank you for taking the time to read this article. Whilst valves are considered user replaceable parts, if you are unsure of or uncomfortable with anything aspect of this article, please contact your nearest Authorised Orange dealer.

“From The Road” is a series focusing on Orange Ambassadors and their touring experiences.

We start the series with a photo update from Sparrows. They’re currently on a 100 day tour (or something ridiculous like that). These Canadians, who describe their sound as “spacey post punk rock,”  almost never leave the road. Check out their new EP, “Cold Ground,” at their Bandcamp.


Hello Orange Amplifier enthusiast. This is Devlin from Sparrows speaking. I play guitar and yell in the band. We’ve been on tour for the past few weeks, and I’m here to share some stories and pictures and other fun stuff from what’s been going on. This is an update from the first half of tour, there’s going to be another update later on with the last half.

Everybody following? Good! On to some pictures.


Our first stop on tour was Cleveland, Ohio. We played a house show thanks to the wonderful lads in Cleveland locals Harvey Pekar. Before the show, as this picture illustrates, we made a brief stop at the Rock And Roll Hall of Fame. They had a Rolling Stones exhibit going, which is fitting because we’ve been listening to Keith Richard’s autobiography in the van.


Day two of tour we played in Chicago, Illinois. One of my personal favourite American cities, Chicago greeted us with some unpleasant traffic getting into the city. We had an interview with Fearless Internet Radio which left us scrambling up some stairs to avoiding being too late. During the whole interview, the pug in the picture was snoring behind us, making for an adorable distraction. We played at Quenchers Saloon that night. Good show, and big thanks to Sam for making that happen!


This picture was taken in St. Louis, Missouri, at a St. Louis Cardinals game. We were all pretty pumped when we managed to score some cheap tickets to a game in one of the nicest ballparks I’ve ever seen. And I’m a big baseball fan. It was a hot and muggy day, but the ball game was a huge pick-me(us)-up. Tour is all about morale and that definitely helped. Interesting show that night, as there was an (insert genre)-core show next door. I don’t think I’ve ever seen a band with that much merch. Probably more weight in shirts than all our gear and trailer combined. Played with Strawberry Girls that night, who ruled. Overall good time


This is what Kansas looks like. It’s almost impressive how little there is to it. You’re driving and all of a sudden you notice the trees are slowly disappearing, then BAM! You’re surrounded by nothing. Just plains that seem to go on miles (kilometers) and miles. I think I took a good dozen pictures of the landscape alone. It’s hard to pick which of twelve pictures of grass is the best, but I think I did well.


Believe it or not, that is a donut. After being cooked to perfection, it was covered in melted fudge and roasted strawberries. That’s the food-truck life of Austin, Texas. One of the coolest cities we’ve been to, it certainly lives up to its reputation as “weird”. I can’t remember the last time I’ve seen that many interesting, we’ll say “characters”, walking by the venue during the show. Thanks to Blake for letting us crash at his place and keep out of what was a pretty deadly Texas heat.


Speaking of Texas, the next day was Friday the 13th, meaning $13 tattoos. And since we were in Austin, I decided to permanently brand myself with the state outline. It works out well that this was the first year we toured into Texas, and it’s 2013 so the 13 inside the outline has a bit of a cooler meaning to me. So deep.


If I had to pick one picture to summarize this tour, this would take the cake. It’s been the tour of van issues. To put it into perspective, we got to Chicago on day two and our steering wasn’t working too well. Take it in and get a ball joint replaced. Back on the road. Get into Texas and realize that one of our tires is ripping. No issue, we have a spare that we can throw on (and by throw on I mean pay a professional to delicately place it on) and we can get on our way. Driving between Austin and San Antonio, we hear something explode and we lose control of the van for bit. We safely pull off the highway and take a look, and the tread on the replacement tire blew up. Wait around 2 hours for a tow-truck, followed by 2 of us going with the van for 2 hours to get all four tires replaced while the other 2 of us wait with the trailer, and we could get back on the road. Touring is expensive.


This picture in no way gets the whole feeling across of what we experienced. After playing some great shows in Texas, we start heading east and get our first taste of Louisiana, specifically New Orleans. Played at the Mushroom, a cool record store that seemed to be in a predominantly student housing area, we took a night trip to Bourbon Street. While we didn’t actually do anything, the walk through was unlike anything anywhere else in the world to me. Just a strip of bars and clubs, packed with people on a Sunday night, and that just breathed energy. Next time hopefully we can go back with a bit more time to spare. Considering as a band we generally (always) pick sleep over party post-show, this would have made an enticing exception.

Right now we’re heading up into Alabama for a show in Birmingham as we start the slow process of making our way home. We’ll have another update coming up in the near future. Hope to catch you then!

Devlin Morton, Sparrows