Tech Question Regarding VH4 Service / Mod - Thank You

angelspade

angelspade

Well-known member
Perhaps I should be emailing Diezel service (Leo Diezel) directly, but I thought that I would ask here first. I have owned a Diezel VH4 and a Diezel Hagen for the last 6 months or so. I recently sold the Hagen after several months of comparisons. It was close on many levels, but in the end I couldn't justify keeping both as they were similar in many regards and I slightly favored the VH4. That said, there is one aspect of the Hagen that I really do miss....That top end "sizzle" on channels 3 and 4. I push the treble and presence pretty hard on my VH4 as I tend to favor brighter / crisper tones, but it does not have the ability to get that cutting top end fizz that is present in the Hagen. So my Question is: Is there a safe and simple mod that can be performed to the VH4 that can add this one tonal aspect to the VH4 without changing the overall character of an amp?

Thoughts are greatly appreciated...THANKS!!!
 
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angelspade said:
Perhaps I should be emailing Diezel service directly, but I thought that I would ask here first. I have owned a Diezel VH4 and a Diezel Hagen for the last 6 months or so. I recently sold the Hagen after several months of comparisons. It was close on many levels, but in the end I couldn't justify keeping both as they were similar in many regards and I slightly favored the VH4. That said, there is one aspect of the Hagen that I really do miss....That top end "sizzle" on channels 3 and 4. I push the treble and presence pretty hard on my VH4 as I tend to favor brighter / crisper tones, but it does not have the ability to get that cutting top end fizz that is present in the Hagen. So my Question is: Is there a safe and simple mod that can be performed to the VH4 that can add this one tonal aspect to the VH4 without changing the overall character of an amp?

Thoughts are greatly appreciated...THANKS!!!
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I would guess higher value pots as that works for guitar?

But I am not competent in this field, so better listen to tech-savvy guys first.
 
CrystalSky said:
I would guess higher value pots as that works for guitar?

But I am not competent in this field, so better listen to tech-savvy guys first.
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Thank you...It could, but my guess might be a bright cap? I'm really not competent either. I'm sure either the resident Diezel rep here (Leo Diezel), or one of the more technically proficient board members will check in eventually.
 
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angelspade said:
Thank you...It could, but my guess might be a bright cap? I'm really not competent either. I'm sure either the resident Diezel rep here (Leo Diezel), or one of the more technically proficient board members will check in eventually.
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Yeah, might be that too. There are people here beside tech support too if you don’t get an answer here soon enough.
 
Fr I think the vh2 had more of that sizzle and I think that’s why I liked the channel 2 a lot . Could be the new 6l6s in it too
 
skelt101 said:
@angelspade
Besides using 6L6s, you might also try a quick modification by moving the negative feedback from the 8ohm tap to the 4ohm tap on the output transformer. You can find details here:
https://www.rig-talk.com/forum/thre...-of-diezel-modifications.208989/#post-2315750
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Thank you. Yes, I had done some research on this mod. It sounds like it may brighten the overall tone and perhaps relieves a touch of compression. People have described it as "opening up" up the amp. Not sure if that is actually what it is doing, or it just presents that way on account of the overall brighter tone. In either case, I am looking for really just the very top end presence (often described as sizzle, or fizz). The Hagen had the perfect amount of this quality and I'm wondering if there is a mod or value change inherent to the Hagen that can be added to the VH4. not sure if this is possible.
 
I'm thinking it could be which Power Tubes are in each amp.

What Power Tubes were in the Hagen and are in your VH4?
If your Hagen had KT77s, and your VH4 has 6L6, then just change to KT77's in your VH4,
and you'll get that sizzle. that's what I'm thinking it is.
 
FLUXX said:
I'm thinking it could be which Power Tubes are in each amp.

What Power Tubes were in the Hagen and are in your VH4?
If your Hagen had KT77s, and your VH4 has 6L6, then just change to KT77's in your VH4,
and you'll get that sizzle. that's what I'm thinking it is.
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I appreciate that, but it's definitely a voicing differential. Anyone who has owned both will likely concur. There is a pronounced sizzle (similar to a 5150) with the Hagen that is absent in the VH4. That said, both my VH4 and Hagen have EL34s.
 
Easiest solutions are to replace the EL34s with 6L6s and rebias. Also, try to get your ears on the same vertical plane as the speaker caps in the cabinet. Meaning, if you’re playing a straight closed-back cab and you’re sitting or standing up, the highest frequencies emanating from the speaker are shooting at your legs or your chest, not your head. Maybe get an angled cabinet?

What speakers are you using currently? Does your cabinet have a thick grill cloth?
 
pipboy90 said:
Easiest solutions are to replace the EL34s with 6L6s and rebias. Also, try to get your ears on the same vertical plane as the speaker caps in the cabinet. Meaning, if you’re playing a straight closed-back cab and you’re sitting or standing up, the highest frequencies emanating from the speaker are shooting at your legs or your chest, not your head. Maybe get an angled cabinet?

What speakers are you using currently? Does your cabinet have a thick grill cloth?
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All great suggestions. I am planning on trying the 6L6s for sure at some point. In regards to the cab, it is a mesa angled V30 cab, and I sit on a low stool to position the angled top speakers at chest / head trajectory. I'm fairly certain that a mod will be required to get what I'm after. Thanks brother, I appreciate the feedback.
 
angelspade said:
All great suggestions. I am planning on trying the 6L6s for sure at some point. In regards to the cab, it is a mesa angled V30 cab, and I sit on a low stool to position the angled top speakers at chest / head trajectory. I'm fairly certain that a mod will be required to get what I'm after. Thanks brother, I appreciate the feedback.
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Mesa V30s are actually a little smoother and darker than Chinese V30s. Diezel uses Chinese V30s in their cabs. So that may be something to try out.
 
Can't help with the mod question - but this is why I have the VH4 and the Hagen and can't ever part with either 😂
 
angelspade said:
Haaa....makes sense. But that crips "sizzle" quality that the Hagen has that the VH4 lacks...You can hear that as well?
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Damn straight... The Hagen's got this wild side to it - I love it - I can rein it in when needed but sometimes??? Man just letting the chords ringing out or going full-chuggah, you can't beat that top end sizzle and bite. I love the Hagen.
 
Herbert is still king to me . I have a few diezels but a 2008 mk 1 is my fav .I can get sizzling and tight tones out of it . I keep 6l6s in it . Have it do say I love as much as my hermanssons and wizards . Honestly love Herbert as much as any amps
 
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