how borked is my amp?

Recording Techniques, People Skills, Gear, Recording Spaces, Computers, and DIY

Moderators: drumsound, tomb

User avatar
tubetapexfmr
steve albini likes it
Posts: 304
Joined: Mon Mar 05, 2007 7:39 pm
Location: Vacuum

Post by tubetapexfmr » Fri Sep 12, 2008 10:02 am

Seriously, check your preamp tubes first. Before you even take it to a tech, start swapping out 12AX7's from position 1 on down the line, one tube at a time (position 1 would be the preamp tube furthest away from the larger power tubes). A whole new set of tubes will probably cost you less than any good tech's minimum bench fee, plus even if it ISN'T the tubes, then you have a backup set you know is good. My guess is you have the original Fender tubes in there and if so those Sovteks are pretty much garbage even when new. Get yourself some JJs or Mullard reissues and more than likely your problem will not only be fixed, but the amp will sound better overall.

User avatar
jv
pushin' record
Posts: 282
Joined: Thu Jan 27, 2005 5:00 pm
Location: Seattle, WA

Post by jv » Fri Sep 12, 2008 10:43 am

A few weeks ago, I recorded a band that was using one of those amps. The amp started making a low-level squealing noise, and it went away when I kicked it. So you might try that :)

Judas Jetski
carpal tunnel
Posts: 1584
Joined: Sun Jan 16, 2005 7:30 pm
Location: The US North Coast
Contact:

Post by Judas Jetski » Fri Sep 12, 2008 3:35 pm

Are you sure there isn't some sort of small animal in a mechanized device somewhere in the amp? I mean, not a motorboat specifically...



Uh, +1 on the "replace the tubes before you see a tech" tip. Spare tubes are never bad to have around, and it might save you a lot of headache.
New Judas Jetski EP up! andysmash.bandcamp.com

www.andysmash.com

RefD
on a wing and a prayer
Posts: 5993
Joined: Fri Aug 27, 2004 9:10 pm

Post by RefD » Fri Sep 12, 2008 4:29 pm

Judas Jetski wrote:Uh, +1 on the "replace the tubes before you see a tech" tip. Spare tubes are never bad to have around, and it might save you a lot of headache.
agreed.

hard as it is to believe, i could be wrong. :lol:
?What need is there to weep over parts of life? The whole of it calls for tears.? -- Seneca

User avatar
johnny7
suffering 'studio suck'
Posts: 406
Joined: Sun Feb 15, 2004 9:57 pm
Location: Seattle

Post by johnny7 » Fri Sep 12, 2008 4:48 pm

I once saw a squirrel that could drive a tiny motorboat. Don't recall any screaming, tho...

A preamp tube going usually sounds like random white noise that fluctuates in volume. If you lightly tap it you can affect the sound. That is my simple test.
Johnny

User avatar
Smitty
tinnitus
Posts: 1246
Joined: Tue Jun 20, 2006 11:14 am
Location: columbus, oh

Post by Smitty » Mon Sep 15, 2008 1:02 pm

i'll do my best to check the tubes. it had new JJ's put in right before i purchased it from the original owner.
"I try to hate all my gear equally at all times to keep the balance of power in my favor." - Brad Sucks

sparky
pushin' record
Posts: 210
Joined: Thu Apr 13, 2006 6:47 am
Location: Brooklyn

Post by sparky » Mon Sep 15, 2008 2:38 pm

I once saw a squirrel that could drive a tiny motorboat. Don't recall any screaming, tho...
are you sure the squirrel wasn't waterskiing behind the motorboat? Waterskiing squirrels, I've seen. pleasureboating squirrels is a whole new level.

Judas Jetski
carpal tunnel
Posts: 1584
Joined: Sun Jan 16, 2005 7:30 pm
Location: The US North Coast
Contact:

Post by Judas Jetski » Mon Sep 15, 2008 3:01 pm

Smitty wrote:i'll do my best to check the tubes. it had new JJ's put in right before i purchased it from the original owner.

Y'know, that kind of reminds me of fresh tires on a used car. Sometimes it means you get a better deal, because the car now has a fresh set of tires. Sometimes it means the car has alignment issues that the seller is trying to hide... and sometimes it means that the seller found a good set of tires at the local Pick'n'Pull, which isn't bad depending on why the tires wound up in the boneyard in the first place (i.e. they might not actually be as good as they look).

The timing of that new set of tubes makes me a little suspicious, especially now that you're having problems with the amp. I'm curious to see where this all leads.
New Judas Jetski EP up! andysmash.bandcamp.com

www.andysmash.com

User avatar
Smitty
tinnitus
Posts: 1246
Joined: Tue Jun 20, 2006 11:14 am
Location: columbus, oh

Post by Smitty » Mon Sep 15, 2008 3:07 pm

well, the whole bottom half of my state is expected to be without electricity for oh, about the next 5-7 days because of the Ike-aftermath that tore through here over the weekend. no power at my place.

plenty of power at work, though. figures. :x

*stalls*
"I try to hate all my gear equally at all times to keep the balance of power in my favor." - Brad Sucks

RefD
on a wing and a prayer
Posts: 5993
Joined: Fri Aug 27, 2004 9:10 pm

Post by RefD » Mon Sep 15, 2008 3:31 pm

this explains why i haven't heard from my friends in Cincinnati.
?What need is there to weep over parts of life? The whole of it calls for tears.? -- Seneca

User avatar
johnny7
suffering 'studio suck'
Posts: 406
Joined: Sun Feb 15, 2004 9:57 pm
Location: Seattle

Post by johnny7 » Mon Sep 15, 2008 4:02 pm

sparky wrote:
I once saw a squirrel that could drive a tiny motorboat. Don't recall any screaming, tho...
are you sure the squirrel wasn't waterskiing behind the motorboat? Waterskiing squirrels, I've seen. pleasureboating squirrels is a whole new level.
Dang, you might be right - he might have been waterskiing and not driving the boat.
If so, who the hell was driving?

This reminds me, i did see a tiny monkey riding a mini bike. He was definitely screaming....

User avatar
Brian
resurrected
Posts: 2254
Joined: Mon Jun 02, 2003 6:00 pm
Location: corner of your eye
Contact:

Post by Brian » Mon Sep 15, 2008 8:46 pm

faulty or missing front plate ground connection, reground to rear. and maybe a bad resistor on the input. Either way, I just totally "re-did" my Fender and it was no biggie. It sounds awesome now. I ALSO put in new output tubes.
Could be a tube. I bet it's a lose joint.
Harumph!

User avatar
Smitty
tinnitus
Posts: 1246
Joined: Tue Jun 20, 2006 11:14 am
Location: columbus, oh

Post by Smitty » Mon Oct 06, 2008 4:50 pm

aaaaaaaaaaand the verdict is....

one power tube dead, one bad, part of the circuit board fried. looks like the shaky power at the venue during the infamous "rain show" is the likely culprit. on a side note, the tech used the phrase "coughing up blood" to describe it's condition on arrival.

total repair bill, $200.

thanks for playing, all!
"I try to hate all my gear equally at all times to keep the balance of power in my favor." - Brad Sucks

RefD
on a wing and a prayer
Posts: 5993
Joined: Fri Aug 27, 2004 9:10 pm

Post by RefD » Mon Oct 06, 2008 5:21 pm

Smitty wrote:total repair bill, $200.
earlier in this thread, ckeene wrote:I'm going with "what is a loose solder joint" for $200, Alex
whoa.

:shock:
?What need is there to weep over parts of life? The whole of it calls for tears.? -- Seneca

User avatar
tubetapexfmr
steve albini likes it
Posts: 304
Joined: Mon Mar 05, 2007 7:39 pm
Location: Vacuum

Post by tubetapexfmr » Mon Oct 06, 2008 8:29 pm

looks like the shaky power at the venue
Well, now you know the importance of good power conditioning. I always tell the bands I work with to have a power conditioner and an isolation transformer if they want to be completely safe in weird venues.

Post Reply

Who is online

Users browsing this forum: No registered users and 39 guests