Diezel Herbert Issue

C

Candiria

Well-known member
I just picked up a NOS Herbert Mk II from Guitar Center. It was in a store in California, so I couldn't check it out in person beforehand.

I got it in about a week ago and as soon as I plugged into it I thought something might be off about it. The addicting low-end I remembered from my MK I just wasn't there, instead it was way tighter but not in a pleasant way. The top end is very bright, fizzy and unpleasant. I've swapped a few preamp tubes, but there's been no real tone change.

I was playing at lower volume mostly, so I thought maybe the master volume was different than the original. Well I cranked it up yesterday and Noon on both channel/master volume (tested mid cut on and off) was maybe as loud as the VH2 at 9:00. Not quiet but that would have leveled my house with the be MK I, and tone was the same unpleasant fizz fest.

So is the MK II that different from a MK I, or did I get Guitar Center'd?
 
Mind sharing ua any pic of your herbert? And serial number? I heard from none other than Peter Diezel himself said his first 50 production of the Herbert was very very tight and its easily recognisable from the unsual or rare front panel design...
 
hopkinWFG said:
Mind sharing ua any pic of your herbert? And serial number? I heard from none other than Peter Diezel himself said his first 50 production of the Herbert was very very tight and its easily recognisable from the unsual or rare front panel design...
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It's definitely a Mk II Herbert. It was new from Guitar Center on clearance. Has the Mk II logo on the front and serial is in the 001/2030's I believe
 
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Looks like it might be tubes. I swapped out the V6 tube and the volume seems more normal now. It's still fizzier than I remember the Mk I being, and I'm way higher on the bass (1:00) than I used to run the Mk I (10:00). I might just need to do a full retube.
 
Retube it fully, then bias it down to about 40-45 ma’s per set of power tubes, not 70-75 as the manual and Peter suggest. Trust me on this, you’ll thank me later. Bigger and better bass, better highs, just all around way better when biased slightly colder.
 
The loss of the lowend and harsh sound could be a symptom of bad or worn powertubes. Check the bias for sure and check the HT fuses and LEDs on the rear panel.
 
VESmedic said:
Retube it fully, then bias it down to about 40-45 ma’s per set of power tubes, not 70-75 as the manual and Peter suggest. Trust me on this, you’ll thank me later. Bigger and better bass, better highs, just all around way better when biased slightly colder.
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This - 100%
 
strungout82 said:
The loss of the lowend and harsh sound could be a symptom of bad or worn powertubes. Check the bias for sure and check the HT fuses and LEDs on the rear panel.
Click to expand...

Yea I checked the LEDs on the back pretty immediately, but there was no warning. I'm going to replace all the tubes. I had done V1-V3, but the main preamp culprit seemed to be V6. I'll still get new power tubes in there. It's the Mk II, so I have no way to bias it myself.

I'll have to find a tech in the area. I've been spoiled with external bias/fixed bias amps for awhile now, and I don't have a go to person for tube swaps.
 
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