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€129.00 *

*Prices incl. VAT plus shipping costs

In Stock, delivery time approx.1-4 working days (Within Germany)
     The delivery times for shipping abroad can be found here.

Class-A Converter:

  • TB-TH.2
  • 6.5x6.5x15 cm
  • 0.117 kg
  • 4251594902171
  TAD CLASS-A CONVERTER-SET (two converters with selected EL84 tubes + english/german... more
Product information "TAD CLASS-A CONVERTER made in Germany"
TAD CLASS-A CONVERTER-SET (two converters with selected EL84 tubes + english/german manual!
converters do permit to replace 6L6GC, 5881, EL34, KT66 and  6V6GT for EL84/6BQ5 tubes and operates them in pure CLASS A. It is  ready to plug in your amp and play. The TAD CLASS-A CONVERTER improves the amp sonically, its sensitivity and reduces the overall loudness so you can crank it up at reasonable volume.
- Class A + Cathode Bias with EL84
- Pure harmonic sweet distortion for every amp
- Extra smooth tone with Triode version
- Mild/soft compression when played clean
- Improves sustain and thickens your tone
- Available as Triode or Pentode version
- Replaces 6L6GC, EL34, 5881, 6V6GT with EL84
- Plug & Play! No adjustments, no modifications
How the TAD CLASS-A CONVERTER benefits your amps voice:
The tone of a CLASS A operated guitar amp is well known from the legendary VOX AC30. Tone gets more alive, the amp responds more directly and musically. It instantly improves sustain, thickens tone and is adding a "three-dimensional" character with decent compression and smooth harmonic distortion when driven to the limit. The overall loudness will be reduced as the Class A as the EL84 tubes provides less output volume. So you can crank up your amp all the way and achieve best sonically performance at reasonable volume ( 8 to 30 Watt, depending on your amp and the TAD CLASS-A CONVERTER version you use).
PEN-Tone or TRI-Tone?
The TAD CLASS-A CONVERTER is available as PEN-Tone and TRI-Tone. Both versions basically provide the same benefits. The PEN-Tone supports the main tonal character of your amp while the TRI-Tone will clearly make it more linear but will compress and saturate much earlier. The TRI-Tone makes it sound much smoother and will drop down power output of to about 8 watts when using 2 TAD CLASS-A CONVERTER.
Both versions will provide you outrageous sustain and let you achieve more even distortion sound when cranked up and still give you perfect control with playing dynamics.
PLUG & PLAY or How to install
Switch off your amp, pull out the power tubes (6L6GC, 5881, EL34 or 6V6GT) and plug in TAD CLASS-A CONVERTER converters including their EL84 tubes, switch amp on. Done!
Size: the TAD CLASS-A CONVERTER is without pins 12cm high (5cm adaptor + 7cm EL84).
1cm air gap between the top of the EL84 and Cabinet is required for mounting and air flow.
The TAD CLASS-A CONVERTER is total self-adjusting. No adjustments, no modifications!
As you do not adjust the bias you might switch back to the original power tubes at any time you want.
The overall power output depends on your amp and the version of TAD CLASS-A CONVERTER converters you use:
               PEN-Tone:        7 - 9 Watt per converter,  14 -18 Watt per pair
               TRI-Tone:            4 - 5 Watt per converter,    8 -10 Watt per pair
A 100-Watt amp with 4 6L6GC, 5881 or EL34 would saturate usually at 100W RMS power output. With TAD CLASS-A CONVERTER? converters it saturates at:
PEN-Tone: with 4 converters about 32 Watt, with 2 about 16 Watt
TTRI-Tone: with 4 converters about 18 Watt, with 2 about   9 Watt
The use of TAD CLASS-A CONVERTER converters is not recommended for amps with Class A / Class AB switching facility (e.g. Fender® Prosonic). These must be used in Class AB position only when using TAD CLASS-A CONVERTER ?.
DO NOT USE  in amps with cathode controled power amps (e.g. Musicman® RD series, Peavey® Classic 75/100 etc.).
DO NOT USE  in amps with serial filament like the Peavey® Valveking series, Blackstar® Series One, Stage 100
DO NOT USE  in amps with automatic Bias controls like Hughes&Kettner with TSC System
Due to the cathode bias operation of the TAD CLASS-A CONVERTER the bias tremolo of the Fender Custom Vibrolux Reverb, Princeton Reverb, Twinolux,  Dual Professional and others is out of function.
Reviews 10
Read, write and discuss reviews... more
Customer evaluation for "TAD CLASS-A CONVERTER made in Germany"
4 Mar 2016

I got pair of Tonebones purchased from local dealer (UralTone in Helsinki). I replaced 4 x 6L6 tubes in my '73 Super Six Reverb (Silverface Twin-family). Amazing sound cranked, with only 16 watts. It's like a AC-15 with 6x10" -alnicos (original CTS). It's hard to beat that - no longer I miss my '76 AC30 TBR so much...

I also tried Tonebones in my other 100W Silverface amp (Quad Rev '72), which is nowadays been "piggybacked" with Mojotone cabinets. With 2x12" Texas Heat & Swamp Thang - it did not sound bad at all either. But - Super Six is now somethin' else...

Excellent product and money well spent!

15 Nov 2013

I'm reviewing the ToneBone Pentode here as a substitute for keeping in a pair of EL34 and the purpose being that I'd like to waste less energy when diming the amp going into a power brake.

On one hand:

It makes good sense of course that I can dampen the signal appr. 10 dB less with the power brake and get the same resulting volume and the power brake's three power resistors and the three large heat sinks they're mounted on hardly get warm. It's nice to not waste all the heat a 50W or 100W amp would generate and force the resistors and heat sinks to dissipate and get rid of.

On the other hand:

It's a hard rock album I'm recording. The amp is losing it's bite. It sounds good. I'd say quite good...but not as great as it does with the EL34 pair in it. It's too nice now and it's pulling back into the speaker. Additionally, the amp is a little noisier now. Hiss is becoming loud enough for me to start thinking about a gate when recording but even so the hiss is now audible when I'm playing. It's not much, but it's there and it's unacceptable. If playing with very clean sounds you probably wouldn't notice but I'm REALLY letting my output tubes have it with a signal already driven hard in the preamp.

It's very simple: Tone is king! I'm changing back to the EL34 pair again.

My amp is a Soldano SLO-100 modded to take EL34 instead of 6L6. The EL84 just doesn't measure up in character. In fact I think it's closer to the 6L6 that I'm already moving away from but it also lacks the 6L6 big bottom end.

The ToneBone is easy to use. I did have quite a lot of trouble getting them into the sockets in my amp though. I filed the pins and the guide in the middle a bit, worked, wiggled and worked...and filed...and wiggled some more until I got them seated properly. I'm open for the possibility that the sockets in the Soldano aren't fantastic, so although I've changed tubes in it before without it ever being a hassle like this at all, I'll give them the benefit of the doubt. I also know of others who have had absolutely no trouble pushing them into the sockets. So yes, they're easy to use and the fact that you don't need to re-bias or anything, enabling you to pop them out and pop the regular tubes back in, is a very nice feature. Especially with amps that you need to disassemble to adjust bias on. That's something I'll never learn to understand - why it hasn't been made easily accessible on all modern tube amps? It's downright stupid to have to go through all that just to adjust bias on your amp....well...

I'm not a big fan of some of the classic Fender amps, but I think that the EL84 would actually be a much better choice for me in, say, a Twin Reverb than the original. Those amps have the presence of an icepick in my opinion and the softening up that happens with an EL84 may very well be the cure I would be looking for there. But that's not what I tested here. I just wanted to mention that I do see the potential for that.

Less power means less heat dissipation - Nice!

Easy to use and to change back forth between tubes - Nice!

A little noiser when amp is driven hard - Bummer!

Sounds a little duller that the higher power tubes - Bummer!

It has to land right in the middle. The ToneBones work just great technically but paired with tubes that kind of defies the purpose, unfortunately it's not a solution for me.

13 Jun 2013

Amazing in my Twin Reverb 65RI : for bedroom level playing, the Tonebone reduces the overall gain drastically and as a result, the amp's natural white noise just vanishes. Dynamics at low volume seem a little bit more compressed, which is actually great for low volume playing. The amp remains quite loud however when increasing the volume : The Tone-bone will not "turn a Fender into a Boogie", but keeping that in mind, it is a fantastic accessory for alternative voicing of the amplifier.

15 Dec 2012

In one word, wow! More sustain, tonal character and less compression at ultra-high gain without losing the specific sound of my amp. I was able to convert my 100W amp to a 15W amp that I can use at home! You rock, TAD!!

1 Nov 2011

Really good job TAD!!!

I just installed pair of these today to my Fender Hot Rod Deville III 212 60W tube amp and... WOW! These tube sockets/converters are really a fantastic value for this price, even the tubes were included. I had also other TAD EL-84 matched pair tubes and I put them in and kept the factory tubes as spares.

My amp was too loud to my taste with 6L6´s and maybe little bit bassy and after these TAD´s I can easily roll clean master volume to about 8-9 (with SPL Reducer attenuator) and the gain channel at more gain switched on to about 5-6 without loosing my ears... The amp still has it´s own type of sound so I recommend these instead of triode versions. If the sound gets too dark/compressed, you can add more treble or use the normal/bright switch from the amp. I use the guitar plug in input 2 which reduces additional -6 dB from the signal.

Very highly recommended!!!

11 Sep 2009

Fantastic Sound!

I replaced the 2x6L6s in my '59 Bassman with two ToneBones and got a new fantastic sound! Amazig!

'ToneBone' should be patented if it is not yet.

It has very big value!!!

Thank you guys!!


22 Nov 2007

I took out the 4 Fender/Groove Tube GT6L6Bs (Sovtek 5881WXTs)from my 1979 Fender Ultra Linear Twin Reverb and put in 2 Tone Bone Pentodes. What a difference. The tone, swirl, chime, its all there!

14 Mar 2007

Really really incredible !! I've fixed a Tone bone triode and daaammmned...!!! I DO not recognize my amp ( 1973 Fender "Pro reverb" ).It sounds better, clarity, richer, the bass are round, highs are smooth and the drive is purely 60/70' with an extraordinary dynamic and punch...A sound I've never heard !!!!

...If you want to play with a sublime real tube-amp, TONE BONE is for you and nothing else. Right

19 Jun 2006

I'playing on strato, tele, or les paul. I've got the tone bone triode and place it in my LONDON CITY DEA 130, replacing EL34. I use DIAMOND J-DRIVE, FULLTONE ECD, MI AUDIO PRODRIVE, VOODOOLAB SPARKLE DRIVE TC ELECTRONICS VINTAGE DISTORSION AND Z VEX SUPER HARD ON.This works very fine, and now I can get the right sounds of my pedals with the crunch of the amp. Before the amp was unusable because too loud. Now it become so sensitive and at lower volume, a real pleasure.

11 Oct 2004

On my DeVille I replaced the matched pair of 6L6GC (GROOVE TUBE originals) with the PENTODE Tone Bone+EL84Cz... Yes, it works! Maybe too much, because the Cz are REALLY powerfull tubes!!

The sound comes out on 50% than before, and I can play the clean channel in complete gain with the volume knob at 7: the crunch I've search for looong times now is in my DeVille...


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