THD amp users' thread

[edgie]

Hi guys,

I noticed that there are now some number of us using THD amps and most of us know that we can do a lot of things with them to suit our personal tastes. I think it would be nice to have a healthy discussion about what we do to our amps in terms of tubes, bias, speakers, etc. I'm hoping we can pick up some tips for each other in the process. : )

So I'll start off with this: For flexi-50 users, try to set the bias of the tubes hotter than the recommended bias. I set mine at 32ma instead of the recommended 25ma. This results in a faster response from the amp and more gain on tap. It's like making your pickup a little hotter but you can control it with either the volume knob on your guitar or the gain setting in the amp.

Anyone?: )

 

[NanoShred]

Bi-valve user. Very happy with the amp. Takes pedals very well and has a unique tone.

I am pairing mine with a mesa boogie wide body 1 x 12 cab with celestion c90 speaker. I love the ones i am getting. Some nice tight bass tones. Those looking for more gain at a lower volume, try using 6L6s. They break up earlier and for a more modern sound a lil more smooth.

I tried JJ 12ax7s too, they do provide more gain but more harsh. I swapped back the stock tung sol tubes. Sound really much sweeter with the thd.

Anyway heres a pic of my amp and cab

 

[edgie]

compact yet cool set-up there nanoshred. I tried the svetlana winged Cs 6L6GC in my flexi but i find them too bassy already. I got better results with a pair of EHX 6CA7EH which are suppose to sound in-between EL34 and 6L6GC. In one of the reviews I read, the reviewer mentioned that it can get you to the sound of THE WHO's pete townshend and I'd agree with him. It has the character of a marshall growl and fenderish break-up happening at the same time. I think its the Hiwatt sound(haven't heard those legendary hiwatts in person so am not really sure) that people discuss over in some other forums.

I also read that swapping tubes have more pronounced effect on the univalve and bi-valve compared to the flexi.

I also dig the tung-sol 12ax7s in the pre-amp. Havent tried putting the spare JJ here though. The Chinese-made Valve Arts EL34s are surprisingly very good. I thought they were just shipped with the amp to cut cost but man, do they have tone!: )

 

[JMguitars]

Univalve

- Unless recording, I never play in the Roll channel. Clean and Dirty can be gotten on the Rock channel as the Univalve cleans up so well on the guitars's volume knob adjustments.

- Replaying both the Input & Driver preamp tubes on the Uni with low gain tubes i.e. 12AU7 and a 6L6 will get you into Fender territory. Throw a reverb pedal in and adjust for taste.

- All things constant, replace the V1 tube with a lower gain alternative for less compression and better tone definition.

- All things constant, replace the V2 tube with a lower gain alternative for less headroom and lower volume level to power amp distorting.

- Leave the orange light off as much as possible, only unless white noise poses a problem.

- Play the Univalve with attenuator switched off (attenuation does affect tone, the more you attenuate, the greater the effect).

- Bring the volume knob at 2 to 3 o clock or wherever you can hear the transition of the tone suddenly becoming warm. From thereafter, the amp becomes distorted without any significant increase in volume.

- You can manage volume by lowering the volume level on your guitar.

- the univalve running on a class A (to my memory) arrangement, will highlight a lot of detail in your playing; if you play sloppy you are going to hear it.

- it is sensitive to cabinet choice. best has always been the thd 2x12 which it has been tuned to. Sensitive to the guitar as well as controls, hence with these type of class A amps you learn to utilise your volume and tone knobs more than when playing through other amps.

- i like to set my guitars at 7-8 on volume knob and 8 on tone knob, then set up the amp accordingly. once tuned to these guitar levels, you can clean up the tone, add more gain, darken or brighten the tone without touching the amp any more.

- if additional volume is required for a gig, you can run a line-out signal from univalve direct into a clean amp combo. likewise, you can use the univalve for cranked power tube distortion and then either direct to board or to a clean amp for playback at reasonable conversation levels.

Flexi

- clean channel is really clean and great for pedal-pushers.

- if I remember correctly, if you swap out powertubes with KT88s, a bassist could actually use the Flexi for bass playing.

- for me, my Flexi liked my LP more than my Strat.

- the bias of tubes can sway after sometime. Check often on the bias when using new tubes as these can sway even within the first day of play.

- some of what I mentioned under the univalve category can apply to the Flexi.

 

[edgie]

Univalve

Flexi

\- for me, my Flexi liked my LP more than my Strat.

- the bias of tubes can sway after sometime. Check often on the bias when using new tubes as these can sway even within the first day of play.

I set the flexi to a very low level of treble when using strat with the cut(which emphasizes upper mids) almost off as it can sound too bright if you are not used to the baxandall-type EQ(to those who have yet to know, it means that the treble, mid and bass can be set without affecting the other so get ready to see some unusual knob settings such as treble = 2, mid = 6, bass = 4). But with LP I dime everything except the bass and of course the volume. The THD 2 x 12 cabinet has lots of healthy bass already so for LP's i just set it at about 1 o'clock.

Yes, i agree that the bias of the tubes needs to be checked constantly especially if tubes are not yet broken-in if you want it running on its optimum. When my flexi arrived, the power tubes are so mismatched in bias but i didn't realize it until i got a multi meter 2 weeks later. But even so, it didn't sound bad nor did it cause damage. Once i set the bias, the sound improved a lot in terms of balance and response. And it's easy to do.

 

[Zerker]

Currently I've been using a Bi-valve 30 with a 2 x 12 THD cab. Pairing it with a Ernieball Musicman Steve Morse. I've yet to change the tubes as I love the tone I'm getting from it. Can't really give much tips because I haven't experimented much with the tubes yet lol. What I really like about this amp is that whatever pedals I've tried using with it, it always sounds great.