I've got the sick (solid state bass) amp blues...

Tim Armstrong · January 29th, 2009, 10:11 PM

The amp is a mid-80s A.M.P. BH-420 solid-state head, 400 watts. No schematic available that I know of (the company was small and short-lived!). It's the amp that the Thunderfunk was based on...

Here are the symptoms (that I now realize have been coming on for a while): somewhat reduced volume, fuzzy overtones, occasionally the volume cuts out and I have to slap my bass pickup to get it working again (and it's not the bass or instrument cables, it doesn't happen with my other amps). Seems like I need to "wake up" the amp that way.

I'm bumming (and I have gigs coming!)...

Any advice appreciated!

Tim

tombm3 · January 29th, 2009, 11:43 PM

It sounds like it may be a capacitor issue. Like it's losing its charge and then, boom, it comes back.

The age of the amp, mid 80's, is some 20 years old. Therefore, if it hasn't been seen for a checkup it's probably time.

Paul in Colorado · January 30th, 2009, 01:46 AM

It needs to be made complient for the change to Digital TV. You are ready for the change to Digital TV aren't you?

Tim Armstrong · January 30th, 2009, 08:16 AM

Quote:

Originally Posted by Paul in Colorado

It needs to be made complient for the change to Digital TV. You are ready for the change to Digital TV aren't you?

Tim

Tim Armstrong · January 30th, 2009, 08:17 AM

Crap, I just remembered smelling smoke at Friday night's gig...

Guess it's going to the amp doc!

Tim

Steve G · January 30th, 2009, 08:50 AM

Could it be the return of the legendary Crate Powerblock Tim?

Tim Armstrong · January 30th, 2009, 10:22 AM

Quote:

Originally Posted by Steve G

Could it be the return of the legendary Crate Powerblock Tim?

Yep, that's my backup!

We're playing a big gig next weekend, a blues festival in a firehouse in Snow Hill, Maryland, and for that one I may use my Yamaha Magic Stomp preamp into a spare power amp, just to get the output up there enough to carry the room...

Tim

Bluesbob · January 30th, 2009, 10:43 AM

I was going to relate how I had the same problem with my SWR combo and it turned out to be the gain pot. I worked around it by turning it up all the way and using my bass volume knobs to control gain. I have to fix it one of these days.
But if you're sure you smelled smoke - that's B - A - D bad.
Maybe you could give Dave Funk a call at Thunderfunk. The phone # is at the bottom of the page.
Good luck, Tim.

Daddydex · January 30th, 2009, 10:44 AM

Quote:

Originally Posted by Tim Armstrong

Crap, I just remembered smelling smoke at Friday night's gig...

Guess it's going to the amp doc!

Tim

I smelled some smoke at Friday nights gig too!

Dan

January 29th, 2009, 10:11 PM	#1 (permalink)
Tim Armstrong Moderator Doctor of Teleocity Join Date: Mar 2003 Location: Ocean Pines, Maryland, USA Age: 50 Posts: 13,152	I've got the sick (solid state bass) amp blues... The amp is a mid-80s A.M.P. BH-420 solid-state head, 400 watts. No schematic available that I know of (the company was small and short-lived!). It's the amp that the Thunderfunk was based on... Here are the symptoms (that I now realize have been coming on for a while): somewhat reduced volume, fuzzy overtones, occasionally the volume cuts out and I have to slap my bass pickup to get it working again (and it's not the bass or instrument cables, it doesn't happen with my other amps). Seems like I need to "wake up" the amp that way. I'm bumming (and I have gigs coming!)... Any advice appreciated! Tim __________________ http://www.moodswingers.org

January 29th, 2009, 11:43 PM	#2 (permalink)
tombm3 Tele-Meister Join Date: Apr 2003 Location: WNY Posts: 246	It sounds like it may be a capacitor issue. Like it's losing its charge and then, boom, it comes back. The age of the amp, mid 80's, is some 20 years old. Therefore, if it hasn't been seen for a checkup it's probably time. __________________ "Ain't much you can beat a Tele for.."

January 30th, 2009, 01:46 AM	#3 (permalink)
Paul in Colorado Poster Extraordinaire Join Date: Mar 2003 Location: Fort Collins, CO Age: 56 Posts: 5,155 3 Photos	It needs to be made complient for the change to Digital TV. You are ready for the change to Digital TV aren't you? __________________ www.tuatha.net "There are only two kinds of music. Fast and slow."

January 30th, 2009, 08:17 AM	#5 (permalink)
Tim Armstrong Moderator Doctor of Teleocity Join Date: Mar 2003 Location: Ocean Pines, Maryland, USA Age: 50 Posts: 13,152	Crap, I just remembered smelling smoke at Friday night's gig... Guess it's going to the amp doc! Tim __________________ http://www.moodswingers.org

January 30th, 2009, 08:50 AM	#6 (permalink)
Steve G Friend of Leo's Join Date: Nov 2005 Location: LeeK (England) Age: 33 Posts: 2,451 64 Photos	Could it be the return of the legendary Crate Powerblock Tim? __________________ "He was a drinkin' man with a guitar problem..." http://www.myspace.com/stevegiddings http://www.myspace.com/hiandlonesome

January 30th, 2009, 10:43 AM	#8 (permalink)
Bluesbob Tele-Afflicted Join Date: Mar 2003 Location: East Suffolk L.I. Posts: 1,246 20 Photos	Smoke = Bad I was going to relate how I had the same problem with my SWR combo and it turned out to be the gain pot. I worked around it by turning it up all the way and using my bass volume knobs to control gain. I have to fix it one of these days. But if you're sure you smelled smoke - that's B - A - D bad. Maybe you could give Dave Funk a call at Thunderfunk. The phone # is at the bottom of the page. Good luck, Tim. __________________ What, me worry?

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