Monday, 30 September 2013

Evil Robot EVR-C30....and finally....Up-Dated....

Sorry to everyone that's's been ages since my last post....I had wanted to do some vids for this post before I posted it....Summer and doin know how it is....I will add the vids as soon as I get round to doing them....Honest....

So I've had my Evil Robot EVR-C30 for a bit now...I still don't like the footswitch (F/S)....I know it's meant to look retro like the amp it's self....but it's nasty and way to big to fit on my pedal board and in my view not up to gigging and that is after all what this amp is all about....Your first tube amp for your first band swaray....The amp itself is built as good as anything with the vinyl covering applied expertly....No flaky seems coming unstuck....The chunky handle is a nice touch....I really....really like the black stove enamel paint on the chassis....very classy....It would have been nice if the front name plate was the same black stove enamel....but I guess the matt black finish looks better on stage.... 

Apart from the F/S the only cost saving measure I can see is the metal back plate that caries the ohm selector switch and F/S's a flat plate that is secured from the back and would have looked so much better if they had kept the one from the prototype looks a bit ugly....oh and the 3 pin power cable input is under the back cover sandwiched between the transformers making it nearly impossible to plug back in without removing the back cover....Why not a hard-wired power would have been better and saved a few penny’s....

It's a class A amp so it gets hot and the tiny fan in the back helps to cool things down....but could be better....One of the first things I did was make up a box to channel cool air more directly over the tubes....very easy to do and works 100 times better....

The speaker in the C30 is specially designed to sound like the very worn in speaker in Phil X's Magnatone Tonemaster that the Evil Robot's are all based on....Apparently the speaker in Phil's amp could fail at any moment and John Kasha went to great lengths to match the tone of this nearly dead speaker.... The amp has a speaker out so that it can be used with a extension cabinet and act as a head unit....

The Vibrato and Loop is one or the other....not both....the Vibrato is very nice....but I'm going to ignore it as I use the tube buffered loop constantly for my delays and reverb....The loop seems to be very transparent and does what its supposed to do perfectly....

The High and Low inputs are awesome and I have been using them more than switching between the A and B channels....If they could be switched via the footswitch together with the channels the amp would be as near to perfect as you could ask for....

The 3-Way Tone Switch together with the Tone Control is again all you need if your playing live with a band....The C30's tone is very in your face and up front sounding....In the Bright position you get a small volume boost that adds some grit which is nice....things never get spiky or harsh....But for home use I have to admit I would prefer a 3 band “bass, middle, treble” EQ.... Don't get me wrong I'm not saying the EQ is the Evil Robot's achilles' heel....but because the C30 will work with so many different tubes and is therefor capable of so many different tones it does scream out for a 3 way tone control....I use a modded Boss GE-7 in the loop that let me tweak the tone....nothing stupidly boosted....just shaped more to my liking....

The Loudness A and B works by adding an extra tube into the you a nice kick between the two channels....This works really well together with the High and Low you the same tone but one is hotter than the other....It's all you need and never leaves you wanting more....

I have to admit when I first played through the amp I said to myself....”OMG....THIS IS SHIT....” It sounded raw and not the amazing sounding tone machine that I was expecting....I put this down to the very nasty looking tubes that the amp came with....I changed the 6V6's for 6L6's then for EL34's and was again very unimpressed....but when I changed the pre amp tubes for 12AU7's the C30 came alive for me....

If I was Fretted Americana, I would ship the amps without tubes....then leave it up to the dealers to show how the amp can sound with different tubes....or at least ship the amps with AU7's instead of AX7's....

When I bought the C30 I knew I wanted it to have EL34's for a British rock tone....I was completely off....I have now gone for 6L6's and ended up with THE best Fender amp....Fender has “never” made....With 6L6's it's tone is unmistakeably a US Pete Townsend rock tone and together with the 12AU7's you get a very passable John Mayer Strat tone using the Low input....with EL34's your in British Jimi Page rock amp territory....I was lucky that I have a large box of old tubes that I could play around with....If your just starting out it could get very expensive to find the tone your happiest with....or you could never find your tone and sell the amp before you find out just how good the C30 is....

When you first get the's in Phil X's loud, brash and awesome....Then you plug into it....and your not loud, brash and are in-fact a worst guitarist than even YOU thought you were....Loaded with AU7's instead of AX7's....the amp becomes more forgiving of the less still gets dirty as you crank the gain and takes boost pedals beautifully....But I do think that 70% of people who try the amp would prefer the “calmed the fuck down” 12AU7 version.


The tubes I'm now using in my Evil Robot are....

V1 - 12AU7
V2 - 12AX7

These are the Channel Tubes....V1 drives Loudness B....V2 then gets added to V1 to drive the Loudness A into giving more gain....

V3 - 12AU7

This is the tube that the Vibrato runs through....A big Thank You goes out to Guillaume Clapeau for this next bit....The Vibrato doesn't work with a needs a 12AU7....I don't use the Vibrato so have to admit to mising that....I do recall first getting the amp with just one 12AU7 and I assumed it was from the loop after I had messed with the tubes....I usually note things like that down for future reference....Again....Thanks to Guillaume for getting in touch and querying this....I had it down as a 12AX7....Never Trust the Internet....

V4 - 12AU7

This is the tube for the FX Loop....If you use the Loop you need to watch the volumes of any Delay and Reverb pedals you use as these need to be set up to not effect the amps volume....Too Low and you will reduce the amps overall volume....Too High and you will drive the Phase Inverter tube giving you more power tube break up but also more compression when the amp gets loud....You need to keep the loop at unity gain....

V5 - 12AX7

This is the Phase Inverter tube....This tube drives your Power Amp Tubes and is responsible for your Power Amp Distortion....If you want to know more about Phase Inverters read this article....HERE....over at Guitar Amplifier Blueprinting . com....

My Power Tubes are 6L6's for a more US tone....

V1 and V2 are both Tung-Sol's....All other tubes are JJ's....


Because of the amp's up front tone....being able to scoop the mids with a 3 band EQ would maybe tame the feeling of nowhere to hide when your playing the amp....”I could be talking crap”....but in Phil X mode the amp was too much for my heavy handed....sloppy playing “style”....The in your face nature of the C30....over time will be a good thing as I'm going to have to become a better player....

I'm not saying that the Evil Robot is the best amp in the world....If your about to buy a Marshall because you want to sound like Angus Young or a Fender because you want that Fender twang....then the Evil Robot is not for you....But the tones you can get with the C30 are some of the best rock guitar tones ever....and that alone makes the C30 worth the asking price....But you also get an amp that sounds and feels like an expensive hand wired tube amp....and I wasn't expecting that from what is after all a cheap circuit board amp....Even at quiet bedroom levels it never looses the dynamics’s and feeling of a loud tube amp....Your playing jumps out of this amp....You have sustain in your fingers and you find out that you are in-fact a better player than you thought you were.... and in the process that puts a big smile on your face....

As yet I have not had a chance to play the C30 properly LIVE....but as it is set up now....this is without a doubt the best sounding amp I have ever owned....It's a ballsy sounding amp that managers to stay sounding ballsy as you drop the volume....”I have never played so quietly and yet still been happy with my tone”....It has the feel and dynamics’s of a hand wired amp three times it's price....The Fender Hot Rod Deluxe is a good amp but it ain't a Evil Robot....the 65 Deluxe Reverb is a better amp and again it ain't no Evil Robot....

Fender....Marshall....Blackstar....ETC....are all going to have to drop their prices or redesign some of their amps because the Evil Robot EVR-C30....has no right being this good....But it is....k.j.


  1. Hey man, thank you very much for the detailed info of the EVR-30! It's hard to find a first-hand review of this little beast, and for someone like me who's thinking about buying one online (no ER dealers in Spain) it clarifies a lot of things :)

  2. Happy to Help....Glad that someone reads this bollocks....Musician’s Friend has some used Evil Robots for silly money....and they ship to our side of the pond....shipment and taxes could make them expensive....but worth a look....Thanks for getting in touch....k.j.

    1. Hey man! I'm not exactly familiar with all the tubes and what not. Noobie you could say but I got myself one of these amps and it sounds awesome with a bad monkey, but without one it just seems dead. You spoke of the preamp tubes and how that helps would you mind explaining it a bit more to me please?

    2. Hi Jo, Give my newer post a read...."Living with my Evil Robot C30...." It is an amp that your going to get the best from when your pushing it with a boost pedal especially when you have it set clean or cleanish. I have just loaded my amp with some Tung-Sol Pre Amp tubes and a set of TAD 6L6s that are working really well but if I were you I wouldn't start messing with the set of good valves is pretty much as good as any another....I have gone with Tungs because they smooth out my playing style more than doing anything major to the tone of the amp. What has made the biggest difference to the amp is putting a EQ pedal last inline in the loop....because the amp has a very forward projecting mid tone it can seem a little harsh if your on your own and not playing in a band....using a EQ pedal will reduce this effect more than messing with the tubes and help with getting the amp in the sweet spot. I spend most of my time playing into the LOW GAIN input....keeping the amp clean then boosting the front with a OD pedal. You say you have a Bad Monkey....try putting it in the Loop and using it as a EQ gain just volume....and using the BMs bass and treble controls to dial in a smoother sweeter tone and see if you like it before buying an EQ pedal. I'll put a vid up to show you what I do with my amp over the weekend. Any questions just ask and I'll do my best to help you out. The Evil Robot is a amp that you have to work to get the best from and if that means giving it a helping hand with a pedal then thats what you need to EQ pedal in the loop makes more sence than dicking about with tubes....k.j.

    3. Hi Jo again....Bad Monkey in the loop....Bad a clean boost it really sucks ass....I remember it being better than that at being clean boost....but obviously not. I have done a quick vid with bad sound....but you will hear whats going on....the clean boost is giving me more volume and better control of the sweet spot and the EQ pedal letting me tweak the tone of the amp that gets lost as you turn down the volume....but you'll see and hear whats going should be up on youboob about now....k.j.

  3. Just to make sure I am reading correctly - you replaced all preamp tubes with AU7's and are running 2 6L6 power tubes and its working fine with that set up ? I am wanting to tame my Robot a bit and was thinking along these same lines.

    1. according to videos from chappers and fretted americana you can run just 2 power tubes and it will work just fine as long as you put them in the first and last sockets leaving the middle 2 empty

    2. according to chappers and lee and fretted americana you can run just 2 power tubed and it will work just fine as long as the tubes are in the first and last sockets, leaving the middle 2 empty

    3. Thanking You f4482....Your Comments are always welcome....k.j.

  4. Hi ajympt, thanks for you comment and I will re-write the post and make it clear what tubes I am now using in the amp....

    the only tubes I have changed are the power amp tubes and V1 and V2 in the pre amp section....

    V1 - AU7
    V2 - AT7
    V3 - AX7
    V4/Loop - AU7
    V5/Phase Inverter - AX7

    hope this is now clear and BIG Thanks for getting in touch....k.j.

  5. Thanks for the clarification- makes more sense, I didn't think I was understanding correctly - your review of the ER is so dead on to my perception of it that I'm definitely interested in the tweaks you have done to yours. I have actually been thinking about fabricating a totally new back panel that would expose the tubes and let me use a real fan behind it to keep it cool- doesn't seem like the little one on there does much other than make whining noise - control panel gets seriously hot after a while -makes me a bit concerned about some of the components longevity. Are you pretty happy with the results of your duct work?

  6. my air duct works amazingly well....the back panel gets nothing more than warm even after hours of loud playing....before the duct it would get very is a class A amp and they do run hot....A lot of amps never had fans and worked fine for years....I think putting fans in tube amps is a Health and Safety thing........the mini fan does work....just needed pointing at the tubes more....I'll sort the ducts measurements out and post them up for you....happy to help....k.j.

  7. Hi there, do you happen to use 4 6L6 tubes or only 2 like on the diagram?

    1. Hi Michaell....When your using 6L6's or EL34's you can only use 2 power tubes and the half power switch no longer works....with the 6L6's the amp will run at 30watts....EL34's it run's at 25watts....with 6V6's you run all 4 tubes for 34watts and the half power switch works....The Evil is still a loud amp with 2 power tubes but the louder you push the less clean you will be of course....The way I have my amp set up with the AU7 in V1 you loose a bit of volume push from the pre-amp and overall gain....with the gain full up think of Pete Townsend, AC/DC....then for more solo gain kick in a Boost Pedal and the amp really sings out....Hope that helps....k.j.

  8. Thanks so much! Couldn't of asked for a better answer! I've liked my C30 since I've got it but the cheap tubes needed to go so I swapped them with some 6L6s like yourself and immediately noticed a tighter sound. My only thing I haven't liked is how fast it does breakup so I think I'm gonna take your advice and switch out some of the preamp tubes. Thanks again!

    1. The C-30 comes with a AU7 in the FX Loop....V4....swop this tube round with the AX7 in V1 and see if you like the cleaner sound....You will not hurt the amp doing this....but if you put anything in the will distort a little....I did try a Tung-Sol AU7 with a gain factor of 17 in V1....but it was not enough gain....I have gone for JJ's that have a gain factor of 25....They clean up nicely but have enough gain to break up perfectly....But try swopping V1 and V4 tubes around....and see what you think before spending any money....k.j.

  9. Great article thanks....been playing my evil robot now for a year, lots of gigs. Haven't even attempted a tube change. I thought it was sounding quite good even with stock tubes....maybe a bit fizzy, definitely very transparent and unforgiving!

    1. Hi Glen....make sure you read "Living with my Evil Robot C30...." I have now settled on the tubes I'm using....Before you do mess with your tubes try putting a EQ pedal last in line in the Evil's will take some of the forgiveness away but none of the Evil's Tone....and thanks for taking the time to write your comment....I appreciate it....k.j.

  10. I also swapped out the stock fan for a high-output low noise 5V 60mm computer fan.

  11. V6 is the Vibrato tube, V5 is the Effects loop... Nice writeup by the way...
    I have a new mod for the C30 that changes it into more of the USA standard 30W version. If you want to know more, email me at:

  12. Hi Evil Roboters,
    I'm a new (second) owner of a C30 Phil X UK voltage and this is a great thread,
    I have a couple of questions, tried mailing but no response to date so I'll try here:-
    1) the preamp tubes (valves) are V1-V5 looking from left to right. Is that looking up or orientating the amp and looking downwards? I want to exeriment with swapping the V1 tube - as per this thread.
    2) The amp has a high gain and low gain input. I like both. Can I input into both and switch using an A/B box.?
    Help please?

  13. Hi Mick....V1 is the small tube right under the Evils High and Low Inputs....Making V5 the small tube nearest the amps transformers....Best tube I've found is a Tung-Sol EEC803S Gold Pin 12AX7....they have gone in all my amps....Make sure you read "News From Planet Evil Robot...."....that thread gives you the tube lay out from John Kesha himself....You can't use an A/B box as both inputs share the'll get a ground loop....I'm working on an switch....If you plug into the amp then plug another cable in the other input then short the second cable out on the other cable's metal housing the amps channel will change over....not got round to messing with it yet....Any question's you only need to ask....k.j.

    1. Thanks Keith, got all that and read the thread you suggested. Since I posted, I also e-mailed John Kasha with the same questions and got a rapid reply. JK states that an A/B switch would work (switching between High and Low inputs) but I'll accept your answer as tried and tested. I don't really need to do it anyway - just being tone greedy!

    2. Cool Mick....That must mean that a Morley ABY does not work....lets be honest the Morley is the worst switcher you can get....Info always good to know....I could have messed about for weeks without your info....Thanks for the comments....k.j.

    3. Bought a Fender A/B/Y pedal, tried it out and it doesn't work.
      It doesn't do any harm or fuse anything, the amp just defaults to High Gain input and won't switch..... so that's going on ebay.
      Fooled around with pre-amp valves and settled for AT7, AX7, AU7, AU7, AX7 (V1-V5) and this works for me with two 6L6's. Sounds best via the Low Gain input.
      My next project is to quiet the fan noise down with a quieter fan and replace the four screws on the back with flight case toggle latches to allow easier access... and get a reverb pedal in the effects loop
      Then my work is done.

    4. I'm wondering if the inputs work like on the Fender hotrod deluxe. It has a high +6db and low +0db. If you use both they default, I always thought, to low level. There's a trick I've used where I plug into high and put a Fender standard footswitch, the bell push looking one, into low. The high input I play through is at the low level when the footswitch is closed but goes back to high when the switch is open, giving a useful +6db boost. Sounds like the evil robot is similar but the opposite way around. May be worth trying the above but with the guitar in low and the switch in high.

    5. I just bougt traded my Fender hrd for an evil robot. I tested my theory re switching the hi and lo inputs and it works.
      Plug your guitar into lo and a simple footswitch with on/off latching switch into hi. When the switch is closed the lo input floats to the level of the hi. When open it goes back to bring lo.
      It's quite as useful as on a Hot Rod deluxe as the hrd has 6db difference which is perfect for cutting through for lead. The ER has it seems, about double the level boost which is a bit too much.

    6. Hello Tricky....I was going to make up switch with a pot to control the amount of boost on the Hi Input....a massive 7 switch unit from a broken Hughes and Kittner amp....but I've just never had enough time....I will have to sort myself out....k.j.

  14. Have you had any luck with different speakers or moving the transformer? I just took delivery of a C30 and cant stop playing the little guy. Its quite surprising how much you can groom your tone with the guitars controls when you don't have what would be considered traditional tone shaping options on the amp itself. The only present gripe I have is the fan is pretty damn loud and will need to be changed out before recording with her I think.


  15. I Emailed Kasha regarding the mods he spoke about and here is the info he relayed:

    Yes, I have a few of them going now. Here’s the detail...

    Configured for 6L6 tubes (2) – $988.00
    Configured with 6V6 tubes (4) - $1090.00
    Turn around estimate 3 – 4 weeks

    Replacing and adding: Tubes, speaker, output transformer, components, heat shield (new feature)

    In addition, I can add a spring reverb for $400.00 switchable. This will add a week to the mod.

    The amp will be fully tested and will be warranted for 3 years, 60 days on tubes.

    Why do it? The amp will sound rich, full body, and warm. The breakup will be old school Zepp, Rush, AC/DC. The C30 is a very good well made amp, but there were things that had to be left out due to the cost target. You will have great difficulty trying to mount speakers by yourself they will hit the transformer. We take care of that in the mod package. Frankly, the Weber Custom is the best sounding in this style amp. I tested over 20 speakers, and none of them produced the tone I was after.

  16. Great Info Cyril....If I was only in the US....To be honest....I'm happy with the C-30 as it is....I can cope with its it to a Fender Blues Deluxe....ruined by a crappy solid state fx loop that burns up the amps board....the C-30 is built like a tank....Moving the transformer seems a tad overkill to fit a speaker with a bigger might be better to have a deeper amp shell made....Tube amps always run hot....the fan keeps the heat from buiding up and with the simple ducting makes it more efficient at doing its C-30 with the duct never gets hotter than a cup of coffee and the duct also does a good job of reducing the fan noise....apart from the duct the only thing that made the C-30 a better amp was a Graphic EQ pedal last in line in the loop to give more control over the amps tone....John Kasha did an awesome job with the C-30 and hope he comes out with more Evil Robots....

    You could swop out the fan for a quiet PC 80mm one....but you will need to power it from a 9V adapter as the amp runs its fan on 5V....have a look at the Fan mod I made for my Egnater uses a Fan Mate to regulate the fans speed to keep the amp cool but stops all the noise....

    Thanks for all the new info....I will add it to the post propper....k.j.

  17. Just reversing the fan made a huge difference in mine. The control face is now warm to the touch instead of hot enough to warm up me coffee. I can only imagine how well the duct cools beyond that. I have sent my C30 off to my amp tech who is squeezing a more efficient speaker into it and also doing a custom bit of wiring to allow the internal speaker to stay on while plugged into my 2x12 cabinet effectively giving me a 3x12 setup on stage. If anyone is interested in this mod, let me know and I can share some photos if that is an option on this blog.

    1. Hi Cyril....If you want to that's no problem....find me on Twitter and Direct Message me....I get a ton of crap spam in this comments section so don't put your email up on here....Do a write up and some pics and you can post whatever you want....k.j.

    2. I've put up an email contact foam on the bottom of the blog....Send me your e-mail and I'll send mine back to you so you can send in your post....k.j.

  18. Hi
    I have a problem with my EVR c30, there's this crackling noise that won't go away, it's not the tubes, had it checked by my tech, and since I bought it as a B stock in one online shop as previously repaired, he can't tell what's wrong with it as he needs a preamp schematic.I tried everywhere I won't name names but no one seem's to have schematic. Shipping it back is not the option as it is just too expencive for me. So could you or you know someone who could give me the schematic for this amp? Thank you!

  19. A great amp indeed. I've left the original tubes in as I love the raw tone. I have however made some other mods that may be of interest.

    Those of you intending to use en external speaker need to do some checking. On early versions (like mine) there was a manufacturing error on some units. When I bought it the dealer told me they were not going to stock it anymore because they had some problems; now I know why, but it is fixable with a minimum of soldering skills.

    The manual states that inserting a jack into the external speaker jack disconnects the internal speaker. On some units it doesn't (the jack socket is incorrectly wired), and this means if you plug in an external 8 ohm cab, you're driving your amp into a 4 ohm load instead of 8. This is very bad and can result in amp destruction and flames, and you can't do anything about it because the impedance selector only switches between 8 & 16 ohms.
    BUT WAIT! Close examination reveals that there is actually an unused 4 ohm tap on the output transformer and it's labelled for easy reading. So I have made some mods to the amp as follows:
    1. replaced the impedance toggle with a 3 position rotary switch to select 4, 8 or 16 ohms. This obviously needs to be rated at 30 watts or higher to carry the load, don't use a small one. Oh and I sourced a black chicken-head knob to match the rest of the amp.
    2. add another output jack socket, so I now have one that leaves the internal speaker connected in parallel, and one that disconnects it.
    3. these are mounted on a new back-plate that I had laser cut from 3mm black perspex.

    Now I can run the amp through pretty much any combination of cabs with no fear of blowing it up. I usually use the internal speaker plus an external 200w Electrovoice ported cab and it sounds awesome. Try a 4x12 for added fun!.

    1. I'll have to look at that....Thanks for posting Bill....I appreciate all posts....but especially ones with cool new info in them....k.j.

  20. Hey guys, new C30 mods à la carte!

    Here's the list:

    Evil Robot mod for C30 model.
    1. Power attenuator cold/hot
    2. Second channel cleaner, less distortion with more jangle and stacked tone POT for full channel separation
    3. Heat reduction include fan, front plate and hood.
    4. Speaker change
    5. Output Transformer change
    6. Effects loop switch on front panel and send return volume
    7. 5W limiter
    8. Conversion to 6L6 or EL34 with mod for safe use
    9. Upgrade Vibrato fuller richer sounding and works with effects loop

    Videos of each mod coming next week. Pricing is available through my contact page (

    Just specify the mod, country and address, and I will send you a quote including shipping. Here's the link:

    Will be starting a new technical blog on amps, pedals and various things. Keep EVR alive, it is one of a kind amp and the new mods will blow you away.

    Videos next week...

    P.S Thanks Keith for this page...

    John Kasha

  21. Here’s the new video with the modified C30.

    This C30 has the following mods:

    Mercury transformer upgrade
    Weber custom speaker
    New low noise fan and hood to reduce heat up to 12 degrees cooler. Stock C30 will run at 105 degrees, new mod runs at 95 degrees on the front panel.
    Upgraded vibrato that works while the effects are engaged
    Power attenuator to adjust power level making the amp tone tighter and wider on demand. Allows you to use EL34 and 6L6 tubes for long term use.
    Extended overall tube life circuitry designed for class A amps
    New clean channel that chimes and jangles with stacked tone pot for wider frequency sweep and will not effect Ch 1 distortion tone (original Magnatone vibe).

    Overall, the amp has more bark, better bass and high response, tubes will last longer, reduced heat, more versatile clean channel, effects that work while vibrato is on and the ability to tighten or loosen the overall tone using the power attenuator.


  22. Hi Keith. i have a question bout the preamp tubes. how did you remove it? just completely pulling it down? or a twist first before pulling down? (clockwise or counter clock?) im swapping out the v1 preamp. im a tube amp newbie, need to take necessary precaution before tinkering. :)