So, Regarding The VH4...

Thats what I’ve experienced with mine.
Setting by ear, around 28ma is best -
6L6 Redbase , or GL KT77 best current tubes.
EI or HG 12ax7C V1 , Chinese in the middle , LPS in the PI.
 
Same for me.
I really like the open and clearer sound of the 6L6's in the VH4 after years of running 34's and 77's. Feels less congested. I felt like I was always trying to dial that factor out. The NFB mod helped for me too with the KT77's in there though.
(RubyMSTR) 6L6 or (GL) KT77- I usually end up running my bias about 30ma.
A nice V1, using a GL 12AX7 at the moment. tbh I think I'm running something different in V2 to tame ch4 a little bit, but I can't exactly recall what's in there right now.
 
I currently have KT77's biased normally in my 2004 VH4, but I prefer 6550's biased cold. I fiddled around in the Axe FX and this was the combination that clearly sounded the best. I've got a set ready for when the KT77's are wiped.

I definitely suggest trying a cold bias, though. Around 45-50% sounded best to me. It clears up the midrange congestion that Diezels sometimes have and will make the amp work better with a variety of speaker cabinets.

Just my two cents.
 
hellzington said:
I currently have KT77's biased normally in my 2004 VH4, but I prefer 6550's biased cold. I fiddled around in the Axe FX and this was the combination that clearly sounded the best. I've got a set ready for when the KT77's are wiped.

I definitely suggest trying a cold bias, though. Around 45-50% sounded best to me. It clears up the midrange congestion that Diezels sometimes have and will make the amp work better with a variety of speaker cabinets.

Just my two cents.
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Huh....I had no idea about the ideal bias range for a VH4. But I do remember when I got my old VH4, I had it re-tubed and clearly remember being told he had biased it "hot". I wonder if that is a key reason I hated that old script VH4; congested midrange is an apt description!
 
Philhouse said:
Same for me.
I really like the open and clearer sound of the 6L6's in the VH4 after years of running 34's and 77's. Feels less congested. I felt like I was always trying to dial that factor out. The NFB mod helped for me too with the KT77's in there though.
(RubyMSTR) 6L6 or (GL) KT77- I usually end up running my bias about 30ma.
A nice V1, using a GL 12AX7 at the moment. tbh I think I'm running something different in V2 to tame ch4 a little bit, but I can't exactly recall what's in there right now.
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I need to give 6L6s a try on mine at some point. I tried KT77s in it but it made the amp super flubby in the bass for me. I then went back to EL34s which gives me the Adam Jones style tones I tend to prefer. Now if 6L6 gived a more open sound I definitely need to give it a shot.
 
MrWoodchuck said:
I need to give 6L6s a try on mine at some point. I tried KT77s in it but it made the amp super flubby in the bass for me. I then went back to EL34s which gives me the Adam Jones style tones I tend to prefer. Now if 6L6 gived a more open sound I definitely need to give it a shot.
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I've got EL34s as well....I definately need to try the 6L6s. It seems like everyone has similar thoughts. I love my VH4, but I really wish there was a light modification that would give the VH4 a touch more cirsp sizzle (like the Hagen) so I didnt have to push the presense so hard.
 
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I put 6L6GCs in my VH4 two weeks ago to capture it into my Quad Cortex.
I tried 28mA per tube at first, but it didn't sound right to me,
so I increased it to 53% at 33mA, and it sounded perfect to me (thru 2x12 K100s, on top of 2x12 V30s).

When I switched back to KT77s, I set the Bias at 32mA per tube (59%)
Sounds perfect to my ears.
I personally love KT77s in my Diezels (VH4, VHX)
 
I kept all 4 diezels atf . I have kt77s in my vh4 atm and hate them . Going back to 6l6s 100
 
skelt101 said:
Did you ever try the negative feedback mod?
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This one:

"If you move the NFB wire from the 8 ohm tap to the 4 ohm tap, what is physically changing is you are sending LESS negative feedback signal back to the phase inverter. The result is less damping of the PI output ( less compressed ) and more harmonic distortion (perceived as more brightness). This is a simplified technical explanation, but you get the idea"
 
angelspade said:
This one:

"If you move the NFB wire from the 8 ohm tap to the 4 ohm tap, what is physically changing is you are sending LESS negative feedback signal back to the phase inverter. The result is less damping of the PI output ( less compressed ) and more harmonic distortion (perceived as more brightness). This is a simplified technical explanation, but you get the idea"
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Yeah, that’s what you want if you want more top end and a more open sound.
 
angelspade said:
This one:

"If you move the NFB wire from the 8 ohm tap to the 4 ohm tap, what is physically changing is you are sending LESS negative feedback signal back to the phase inverter. The result is less damping of the PI output ( less compressed ) and more harmonic distortion (perceived as more brightness). This is a simplified technical explanation, but you get the idea"
Click to expand...
Yep, that’s the one. Probably about as simple as it gets for a modification.
 
FLUXX said:
I put 6L6GCs in my VH4 two weeks ago to capture it into my Quad Cortex.
I tried 28mA per tube at first, but it didn't sound right to me,
so I increased it to 53% at 33mA, and it sounded perfect to me (thru 2x12 K100s, on top of 2x12 V30s).

When I switched back to KT77s, I set the Bias at 32mA per tube (59%)
Sounds perfect to my ears.
I personally love KT77s in my Diezels (VH4, VHX)
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Since you've been experimenting and capturing- You wouldn't happen to have any comparison clips would you? At some point I may have to do this if someone else hasn't already.
 
mesa4x12er said:
Since you've been experimenting and capturing- You wouldn't happen to have any comparison clips would you? At some point I may have to do this if someone else hasn't already.
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I'm sorry, I didn't.
The 6L6s have a certain high-end sizzle.
The KT77s have a certain mid-congestion.
I prefer the mid-congestion. Others prefer the hi-end sizzle.
Only your ears, in the room, can decide which is right for you.
 
I think I may have to try the previously referenced NFB mod and the 6L6s. I guess I can always go back as the mod it easily reverse. I love my VH4, but definitely like the idea of a slightly brighter, more present and aggressive flavor in the top end. That's the thing I miss most about the Hagen.
 
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angelspade said:
I think I may have to try the previously referenced NFB mod and the 6L6s. I guess I can always go back as the mod it easily reverse. I love my VH4, but definitely like the idea of a slightly brighter, more present and aggressive flavor in the top end. That's the thing I miss most about the Hagen.
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I tried and I loved it, but I switched back to 8 ohm after a couple of week, simply to see if it was better on the 4 ohm tap or on the 8 ohm. Pay attention to the resistor and the condenser you have there, I use a FL cab and bass are less prominent, all the controls, mids are less "congested", and being naturally more scooped on the 4 ohm, you can crank them more without sound honky. Deep control sounds good at 3 o'clock with no boomyness. I'm thinking to rewire it on the 4 ohm and increase the value of one resistor to have a bit more bass. The solution to avoid this is change the cabinet in favour of a rear loaded one.
 
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