It is currently Mon Mar 16, 2020 8:05 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 31 posts ]  Go to page Previous  1, 2, 3  Next
Go to page Previous  1, 2, 3  Next
Author Message
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Thu Jan 01, 2015 11:37 am
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Wed Jul 07, 2010 5:58 pm
Posts: 385
Location: Montana
shimmilou wrote:
V4, half is reverb recovery and half is final gain stage for vibrato channel. If you unplugged both reverb cables and the hiss remains, you might be looking at the circuit around the V4 half that is the final gain stage for the vibrato channel.

Is the noise present on both channels or only one? Have you tried a known good tube in V4? You could even swap V1 and V4 as a quick check. This isn't definitive but might be telling, by putting the suspected noisy tube on the normal channel only, then see if the noise is still present on both channels, or only one channel. :idea:


It is the same on both channels. These amps have the reverb and vibrato on both channels also...

_________________
In the hands of the right people it can change the world. Not bad for a hunk of ash, a few magnets, and some wire.
Band Site
http://www.reverbnation.com/bigskybluesband
Demos
http://www.youtube.com/user/bigskybluesband


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Thu Jan 01, 2015 3:41 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
majorbytes wrote:
Yep did that, pulled out the preamp tubes one by one and powered it up.. The v4 one took out all of the hiss, but no sound from the speaker..



I understand noise is every where .

Are you sure it is not reverb and / or reverb cables ?


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Thu Jan 01, 2015 5:02 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Fri Aug 21, 2009 1:45 pm
Posts: 852
Location: SoCal323
I owned a trri once and if I remember correctly, doesn't it have both a hum balance pot as well as a bias pot? There are instructions in the manual on how to reduce the hum by adj. the hum balance pot. Just thought I'd throw that out there since it hasn't been brought up. Hope it helps.

_________________
Its a lifestyle.....

Image


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Thu Jan 01, 2015 5:06 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
socal323 wrote:
I owned a trri once and if I remember correctly, doesn't it have both a hum balance pot as well as a bias pot? There are instructions in the manual on how to reduce the hum by adj. the hum balance pot. Just thought I'd throw that out there since it hasn't been brought up. Hope it helps.



Hum balance is for ...hum not for hiss


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Thu Jan 01, 2015 5:14 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Fri Aug 21, 2009 1:45 pm
Posts: 852
Location: SoCal323
stratele52 wrote:
socal323 wrote:
I owned a trri once and if I remember correctly, doesn't it have both a hum balance pot as well as a bias pot? There are instructions in the manual on how to reduce the hum by adj. the hum balance pot. Just thought I'd throw that out there since it hasn't been brought up. Hope it helps.



Hum balance is for ...hum not for hiss


I understand, but one mans hum could be another mans hiss... :wink: Without a audio sample, I don't know for sure. So I recommended this as a possible solution.

_________________
Its a lifestyle.....

Image


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Thu Jan 01, 2015 7:20 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
majorbytes wrote:
shimmilou wrote:
V4, half is reverb recovery and half is final gain stage for vibrato channel. If you unplugged both reverb cables and the hiss remains, you might be looking at the circuit around the V4 half that is the final gain stage for the vibrato channel.

Is the noise present on both channels or only one? Have you tried a known good tube in V4? You could even swap V1 and V4 as a quick check. This isn't definitive but might be telling, by putting the suspected noisy tube on the normal channel only, then see if the noise is still present on both channels, or only one channel. :idea:


It is the same on both channels. These amps have the reverb and vibrato on both channels also...


Hold up! majorbytes, you hijacked the thread....I was trying to address the OP's problem and didn't notice that you had jumped in there. :oops:

The '68 CTR is quite different from the '65 RI. Frankly the '68 VM series are typically more noisy than the RIs anyway.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Fri Jan 02, 2015 2:11 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
shimmilou wrote:
m
Hold up! majorbytes, you hijacked the thread....I was trying to address the OP's problem and didn't notice that you had jumped in there. :oops:

The '68 CTR is quite different from the '65 RI. Frankly the '68 VM series are typically more noisy than the RIs anyway.



+1 I did not notice too . :(


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Sun Jan 04, 2015 3:50 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Wed Jan 15, 2014 2:23 pm
Posts: 311
Location: Marin County
I welcome all information related to my topic here, so no worries. It may help me get more familiar with the terms and pats of the amp.


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Wed Jan 07, 2015 6:48 am
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Wed Jul 07, 2010 5:58 pm
Posts: 385
Location: Montana
Sorry about hijacking this thing, I was just meaning to put some of the troubleshooting I have done with my 68 Twin Reverb to try and solve the hiss issue.. :o

I tried the 5751's, no luck, still got the hiss..

_________________
In the hands of the right people it can change the world. Not bad for a hunk of ash, a few magnets, and some wire.
Band Site
http://www.reverbnation.com/bigskybluesband
Demos
http://www.youtube.com/user/bigskybluesband


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Sun Jan 18, 2015 4:46 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Wed Jan 15, 2014 2:23 pm
Posts: 311
Location: Marin County
So I finally took a look behind this little honey and I noticed that not all the tubes were lit, so…

Image

Then I did the heat/touch test and noticed that one of the 6L6s definitely appeared to be burned out. 2 of the little 12 AT 7s looked like they might be burned out (though I didn't remove their individual covers) but all of those felt warm to the touch on the outside.

Any of this info shed any new light to the more experienced out there?


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Sun Jan 18, 2015 5:13 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
The two preamp tubes that you don't see the heater glow are both 12AT7s (first is reverb driver, second is the PI), and that is normal. If they are warm they are likely good. If the first 12AT7 wasn't working, you would have no reverb, and if the second 12AT7 wasn't working you would have little or no sound out.

The output tube however, should be too hot to touch. Try swapping the output tube to another position and see if it is the same tube not lit, or if it stays with the position.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Sun Jan 18, 2015 5:31 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Wed Jan 15, 2014 2:23 pm
Posts: 311
Location: Marin County
Ok, I'll try that.

Ok… tried that… swapped the two far left output tubes. Same results with different tubes. The 2nd one from the left is definitely still cool to the touch and not glowing. Too bad. I thought I was onto something. I guess I need an experienced pro to look at it.

Thanks for the earlier reply.


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Mon Jan 19, 2015 2:13 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
Ghastly wrote:
Ok, I'll try that.

Ok… tried that… swapped the two far left output tubes. Same results with different tubes. The 2nd one from the left is definitely still cool to the touch and not glowing. Too bad. I thought I was onto something. I guess I need an experienced pro to look at it.

Thanks for the earlier reply.


Bring it to a tech , or learn how to tightened socket pins.


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Mon Jan 19, 2015 6:02 am
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Wed Jan 15, 2014 2:23 pm
Posts: 311
Location: Marin County
Yea, I'm gonna do that.

Hmm. Does this sound like something related to the socket pins? Please elaborate.


Top
Profile
Post subject: Re: Twin Reverb Amp hiss- gate/noise supression pedal?
Posted: Mon Jan 19, 2015 6:54 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
Ghastly wrote:
Yea, I'm gonna do that.

Hmm. Does this sound like something related to the socket pins? Please elaborate.



If no ( or intermittent ) 6,3 volts AC on pin 2 an 7 there must be something wrong in the amp check for broken solder on printed circuit board .

If AC voltage are there , tightened socket pins may help .


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 31 posts ]  Go to page Previous  1, 2, 3  Next
Go to page Previous  1, 2, 3  Next

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: