How dead quiet??

[stefvorcide]

How quiet is supposed to be herbie??? I'm VERY anal about noize or hum nowaday. But I'm wondering if it's the power tubes or just the AC ?? I get the hum at bedroom level (maybe just a hair higher)

My clean is getting a little hum chan 2+ and 3 as well. I still have the hmm if i plug the axe into FX loop return, hence why i'm suspecting the power tube.


I have an ISP decimator pro rack G, but I don't think it's absolutely necessary at this playing level...beside, it kills sustain.

I still have the EL34, maybe herbie is ready for them 6550 ?? or I need a power conditionner??

Edit: I removed the 2nd pair of powertube, one was microphonic... still same problem.

 

[SpicedMuffin]

sounds like you might need a tube change
how long have you had your herbie?

 

[stefvorcide]

3 weeks maybe, bought it here from another canuk.

I'm really thinking about new tubes. maybe 4x 6550 and 2x Tungsol EL34B

 

[PaulyPanacea]

Every tube amp has noise. BUT the Herbert ( the Diezels) have very little..unless you have a bad preamp tube or even bad power tubes. I have all 6550's in my Herbert & i love it. If your tubes are going or are bad, then you will have some noise. Otherwise the amps have little to no noise whatsoever. try swapping your preamp tubes around. may be an easy fix.

 

[stefvorcide]

Every tube amp has noise. BUT the Herbert ( the Diezels) have very little..unless you have a bad preamp tube or even bad power tubes. I have all 6550's in my Herbert & i love it. If your tubes are going or are bad, then you will have some noise. Otherwise the amps have little to no noise whatsoever. try swapping your preamp tubes around. may be an easy fix.

Yeah, did that, but even if i plug my guitar straight into the FX return (skipping the whole pre section) I have the hum...

 

[SpicedMuffin]

yeah if you bought it used you should prob change the tubes
i have 4 kt-88's and 2 6550's in my herbie sounds awsome

 

[duesentrieb]

1) Swap preamp tubes (esp. V1 and V2)
2) Pull power tubes pairwise to locate the "humming" pair
3) report

 

[stefvorcide]

1) Swap preamp tubes (esp. V1 and V2)
2) Pull power tubes pairwise to locate the "humming" pair
3) report

Do I have to remove the fuse if I remove a pair ??

I have hard time with the trim pot, the JSX i had was easier


EDIT: 2nd problem: I put Sovtek 6550WE in the inner pair, and the 3rd fault indicator led starts...no mA reading neither. Bad tubes or herbie just doesnt accept these ones???

is V4-v5-v6 used when you plug into FX loop return??

 

[Wizard of Ozz]

The Herbert should be DEAD QUIET at bedroom levels. Diezels are one of the very few high gain amps out there with a very low noise floor. Several things could be causing your problems including preamp tubes, poor input current, cables, pickups, etc.

EL34s in and of themselves are not the cause.

 

[duesentrieb]

a) Do I have to remove the fuse if I remove a pair ??

b) I have hard time with the trim pot, the JSX i had was easier

c) I put Sovtek 6550WE in the inner pair, and the 3rd fault indicator led starts...no mA reading neither. Bad tubes or herbie just doesnt accept these ones???

d) is V4-v5-v6 used when you plug into FX loop return?? [/b]

a) no
b) sure, but you had to mod the amp when you used all 8-PIN powertubes from 6V6 to KT88. Not with Herbert, one pot fits them all, you know . . . just takes sensible fingers
c) wrong bias or bad tubes, replace fuse (500mA slo blo) and try again
d) V4 and V5 for loop, V6 is the phase inverter

 

[stefvorcide]

a) okay
b) I see, didnt try anything else but el34 and kt77 in that amp tho. it was just more convinient without a screwdiver
c) oh well, gonna get refund.
d) thanks, I should read more the tech corner on the website;p


Meh, I just think I need a power conditionner... or i'm a total n00b. I tried different combination, with some new 12ax7. and I think the new EL34b pair is good.

Either way, thank you Olaf for the help, you rule. i,ll figure whats the "problem" sooner or later I guess.

 

[axeman81]

just wanted to say that if you set the prorackG correctly, it should -not- kill sustain! which is why I paid 4x the price of any other noisegate just to have it do the job right