NGD - Questions - Preamp Tubes in 2022 VH4 and Ch 3 compression

glowe

Member
Hey All ,
Just picked up a brand spanking new 2022 VH4 , owned a Herbert about 8 years ago and regretted parting with it,fantastic Diezel tone ,, , so added a VH4 to the list ,
I can see it comes with Red Base Tad 6L6's , What are the manufacturer of preamp tubes in there ? sorry , I'm too lazy today to pull the back panel off as there other heads stacked on top and access is limited lol ,,
also
This is a played out subject ,, but i'll ask ,,, I now know what the talk is with Ch 3 compression , it's a tiny bit overly compressed/muddy with single note riffing (Gain running at 1-2 o'clock , especially lower frets/strings , still a crushing tone nevertheless ,,but,, I've heard of maybe replacing V3 with a 12AT7 tube ? ,, Any advice would be greatly appreciated , ,Jens @ Kruse does a killer mod , but I really don't want to go that route ,,,, perhaps maybe not yet ,,, ha , this is still a crushing amp and very glad to of pulled the trigger !! Cheers and Thanks all . Happy New Year !
 
Last edited:

skelt101

New member
@glowe
I recently purchased a VH-2 that was loaded with Tung-Sol preamp tubes across the board. (Power tubes were TAD Redbase EL34s.) For a description about the functions of preamp tubes, check out the Service Manual, page 38:
https://www.diezelamplification.com/manuals/service/service-manual_V1-1.pdf
I’ve read that a simple modification for a less compressed sound is to move the negative feedback wire from 8 ohm to 4 ohm.
 

FLUXX

Member
Congrats to both of you on your new Diezels!

@glowe
I tested a 5751 in my VH4's V2, V3, and V6, and i didn't like it in any spot. It spread out the texture of the saturation in a bad way IMHO in V2, V3,
and lowered the volume and body of the FX return in V6, so I didn't stick with it.
You might get better results with an 12AT7. Please let us know if you do.

Also, I'm planning on having Jens Kruse do all his killer mods on my Diezel VH4,
and my Engl Invader 2. The mods are defeat-able, so we don't lose anything by adding them.
I'm really impressed with what he can do to Ch 3 of the VH4, as well as the other channels.
Love his Variac option.

@skelt 101
Great info on the VH4 mod!
How do those Red Base EL34's sound?
 

glowe

Member
Congrats to both of you on your new Diezels!

@glowe
I tested a 5751 in my VH4's V2, V3, and V6, and i didn't like it in any spot. It spread out the texture of the saturation in a bad way IMHO in V2, V3,
and lowered the volume and body of the FX return in V6, so I didn't stick with it.
You might get better results with an 12AT7. Please let us know if you do.

Also, I'm planning on having Jens Kruse do all his killer mods on my Diezel VH4,
and my Engl Invader 2. The mods are defeat-able, so we don't lose anything by adding them.
I'm really impressed with what he can do to Ch 3 of the VH4, as well as the other channels.
Love his Variac option.

@skelt 101
Great info on the VH4 mod!
How do those Red Base EL34's sound?
Thanks for the info FLUXX ,, Yes, Kruse Kontrol Dekom mod sounds fantastic with what I've heard ,
My Herbert def did not possess this compression characteristic,That was prob the best high gainer I've owned ,, and I've gone thru most of them ,, but I've always coveted a VH4 and I was offered one unexpectedly ,new in box for a stellar price , the stars aligned lol ,
I have not played the amp at band volume yet , if this is just a characteristic at lower volume , and wakes up with some SPL increases , then I would be good to go , My SLO and Modern Classic II woke up after band volume , different beasts once the masters got to 4-6
Cheers
 
Last edited:

Techdeth

Well-known member
Thanks for the info FLUXX ,, Yes, Kruze Kontrol Dekom mod sounds fantastic with what I've heard ,
My Herbert def did not possess this compression characteristic,That was prob the best high gainer I've owned ,, and I've gone thru most of them ,, but I've always coveted a VH4 and I was offered one unexpectedly ,new in box for a stellar price , the stars aligned lol ,
I have not played the amp at band volume yet , if this is just a characteristic at lower volume , and wakes up with some SPL increases , then I would be good to go , My SLO and Modern Classic II woke up after band volume , different beasts once the masters got to 4-6
Cheers
It does open up louder . Also I find my Vh4 sounds way less compressed after being on longer . At about an hour in it just sounds better. I’ve tested this because it was driving me nuts lol.I leave it stand by along time before it’s time for use
 

glowe

Member
It does open up louder . Also I find my Vh4 sounds way less compressed after being on longer . At about an hour in it just sounds better. I’ve tested this because it was driving me nuts lol.I leave it stand by along time before it’s time for use
Thanks Techdeth ,, Noted , Ive been playing it the last 1/2 hour , now I'm going to go make dinner and leave on standby LOL What year is your VH4?
 

Philhouse

Well-known member
In my Silverface 2010 I like a 12AT7 in V2 and feel it helped tame CH4's huge compression a bit. Much more usable for me. I also only run the gain on that channel around 10:30 - 11:00.
I did the NFB mod by moving the wire to the 4 ohm tap. Helped open up the amp overall. It does seem to make the volume come on a little faster on the dial, so there is that. It's an easy 10 min mod, and easy to reverse if you don't like it. I run Gold Lion KT77's in it and find them less compressed than the Ruby's that were in it previously, esp against the 34's originally. I also run a nice GL 12AX7 in V1. I want it nice from the start of the signal chain.
I have another Blue face RI running 6L6's and it sounds slightly more open and crisp in comparison. It's only a small percentage change though, and more a feel, and unless you have them side by side to A/B.
 

skelt101

New member
Congrats to both of you on your new Diezels!

@glowe
I tested a 5751 in my VH4's V2, V3, and V6, and i didn't like it in any spot. It spread out the texture of the saturation in a bad way IMHO in V2, V3,
and lowered the volume and body of the FX return in V6, so I didn't stick with it.
You might get better results with an 12AT7. Please let us know if you do.

Also, I'm planning on having Jens Kruse do all his killer mods on my Diezel VH4,
and my Engl Invader 2. The mods are defeat-able, so we don't lose anything by adding them.
I'm really impressed with what he can do to Ch 3 of the VH4, as well as the other channels.
Love his Variac option.

@skelt 101
Great info on the VH4 mod!
How do those Red Base EL34's sound?
Sorry for the delayed reply, FLUXX! My amp came from the factory supplied with the Redbase EL34, but has since been switched to the Redbase 6L6GCM. I wouldn’t call the difference night and day, but perhaps the EL34 was a little more compressed and midrange forward, whereas the 6L6 are more open and sparkly on top. Since my cabinet already has a ton of midrange (Mesa 4x12 Traditional), I prefer the 6L6. I also tried a TAD 7025 in V1. Unfortunately, that didn’t last too long before it started to become noisy (crackles and pops). Put the stock Tung-Sol back in and all is good. I would like to try the NFB on the 4 ohm tap. Sounds like it would be a winner for me!
 

FLUXX

Member
Sorry for the delayed reply, FLUXX! My amp came from the factory supplied with the Redbase EL34, but has since been switched to the Redbase 6L6GCM. I wouldn’t call the difference night and day, but perhaps the EL34 was a little more compressed and midrange forward, whereas the 6L6 are more open and sparkly on top. Since my cabinet already has a ton of midrange (Mesa 4x12 Traditional), I prefer the 6L6. I also tried a TAD 7025 in V1. Unfortunately, that didn’t last too long before it started to become noisy (crackles and pops). Put the stock Tung-Sol back in and all is good. I would like to try the NFB on the 4 ohm tap. Sounds like it would be a winner for me!
That's cool you found the tone you want. Let us know how that NFB mod sounds.
The VH4 is such a brilliant amp.
 

Ventura

Well-known member
CONGRATS on a sweetass new amp. What a magnificent amp at that!! Love my Diezels.

I can't fathom wanting to mod it right off the bat. The Diezels, all of them VH4 included, take some time to learn their inherent characteristics. I've learned not to even bother worrying about tubes if it came factory direct aside from re-seating them all upon delivery to make sure they're in good n solid.

But... First recommendation is the interplay between channel volume vs master volume - crank one, leave the other - and vice versa - this changes the compression ratio of Ch.3 and 4 significantly. Wide open preamps into an attenuated power section, versus higher up on the MV being fed minimally from the preamps.

Play around with it - and also walk around while playing - get a sense of that sound-in-the-room when you're playing. I'm often surprised as what's actually coming out of the amp compared to what I *think* my ears are hearing. They're a very unique amp - across the board but most certainly the VH4. It's got a particular character and I love it.

Just perhaps spend some serious time getting to know it - and the Ch vs Master volume interplay.
Have fun!!
Unkle Mo
 

Dyllheaven88

Well-known member
But a ruby HG in a v3 it def helps a bit with ch3 I’m still learning the amp mine also came with red base el34s and is a 2022 model. Killer amp tho for sure !
 
Top