Trouble-Shooting, Repair and Restoration

Chicago Guitar and Amplifier

feeds@yuku.com (Delicious Bass) — Tue, 03 Nov 2009 14:52:17 GMT

Upon Warandhairstyle's glowing recommendation, had my 470 all ready to send up there to Chicago for CGnA to work their magic and found that they are temporarily not taking solid state amps! Dude said they were backed way on up with tubes and might be ready to look at something transistory after the first of the year. Hmph! Doesn't seem right to discriminate...

Just thought I'd share my disappointment with y'all. Oh well. Somewhat fortunately, I don't have a...

270 201 handles

feeds@yuku.com (sickbird) — Mon, 02 Nov 2009 05:14:02 GMT

hi,

does anyone know where to get the recessed handles for the 270 370 201 (and other) models? are they still being produced by someone?

thanks

126 speaker question

feeds@yuku.com (bumnote) — Sun, 01 Nov 2009 15:23:16 GMT

I just picked acoustic amp no 3 today a 126, to add to my 150b/404, and 220/406

The loudspeaker has a red surround, like the picture in the wiki. Why is this when virtually everything else I have ever seen has a black surround? is there anything different about this speaker

Also all my amps are fairly noisy, [hiss and hum] which doesnt really matter on stage but is irritating. Were they always a bit noisy or do particular components deterioriate over time?

125 - volume loss after some minutes

feeds@yuku.com (barn) — Sat, 31 Oct 2009 07:40:16 GMT

hi there, i just got an old broken 125 as a present and i'd love to get it back to work as i'm surprised how good it sounds. the amp operates just fine for some (10?) minutes, until suddenly the volume drops and from there it goes randomly up and down between very low and normal. i looked for visible broken components and stuff and i even could find some small ceramic caps (27pf, 150pf, 680pf) on the potentiometer-board, that have seen better days, but nothing is really burnt or...

Speaker replacement for '76 115 combo

feeds@yuku.com (rivertramp) — Thu, 29 Oct 2009 22:35:38 GMT

Hey folks, this is my first contact with this community, I'm looking for suggestions. I picked up a 115 combo for guitar fairly cheap, took it home, had an annoying buzz, but liked the sound. Found out the magnet had cracked, called a speaker tech, he figured it was probably the voice coil gone buzzy, said there was no real fix for the cracked magnet. So, what I'm looking for is suggestions for a speaker replacement as a guitar player. I know the old square magnet ones are Eminence,...

370 Fuzzy Sounding, help!

feeds@yuku.com (JonCarr) — Wed, 28 Oct 2009 17:10:14 GMT

I have a 370 head that is running through a full range mesa 1416 diesel cab (1x15", 1x10", 2x6").
It sounds incredible and loud as hell when I first turn it on, but more and more in the last year
it has begun to sound fuzzy and quieter after it warms up for a minute or two.
the amp is especially distorted when turning the volume up over half.
any ideas?

Acoustic G120-112

feeds@yuku.com (gbono) — Wed, 28 Oct 2009 15:18:08 GMT

Pre-amp section doesn't work and I would love a schematic. Don't know if Pirk is online these days?

450 troubles

feeds@yuku.com (JoePesci87) — Thu, 22 Oct 2009 18:28:00 GMT

I've been playing through a 450 for about a year now and couldn't be happier except last week it broke. I was playing and turned the distortion slightly up (still wasn't even what I usually play it at) and thirty seconds later the volume cuts drastically. Tried other cabs with no luck. Any idea what caused this? No visibly burnt resistors, bad joints, caps, etc. Transistors maybe? Do you think the transistors could have just worn out after 30+ years or will I have to rip...

160 reverb problem

feeds@yuku.com (foxfire) — Tue, 20 Oct 2009 16:03:55 GMT

the reverb on my 160 isn't working. i pulled the chassis and pan out. if i tap on the pan i can here it affecting the sound but it's definitely not reverbing as it should if at all. i found that my reverb send is shorted to ground. i traced it back to the driver (i think) transformer. i see that one leg goes to ground and the other goes to the reverb pan and a 0.12mf cap to ground. i'm getting continuity between those 2 legs of which doesn't seem right but i'm not...

INDUCTORS! INDUCTORS! INDUCTORS! FOR A 320 HEAD!

feeds@yuku.com (72jazz) — Tue, 20 Oct 2009 11:40:29 GMT

Please....is there a doctor in the house? I'm in desparate need of help! One week to go!

Where oh where can I find some of these,
please let me know right now.
For if I don't find, some of these please,
I'm going to have a cow!

Well hopefully that got someone's attention! And now, time for the re: inductor 320 email song!

"Lastly, you have a sum total of 5 inductors that not factory
original.. They have been...

Footswitch Issue for a 270 Head

feeds@yuku.com (Trickbunny) — Tue, 20 Oct 2009 08:07:56 GMT

Hey y'all,

The biggest issue is that I don't *have* the footswitch for my 270 head and Ebay isn't exactly bursting with them.

My question, if anyone knows the answer, is- Can I use a generic 2 button footswitch with a stereo 1/4" to 1/4" cable. The 270 head features a tremelo and a fuzz/reverb switch and, honestly, I'd be happy with a switch that would turn at least one or the other on/off.

Thanks...

transistor for a 140?

feeds@yuku.com (kingfausto) — Mon, 19 Oct 2009 20:08:22 GMT

i just got this email from the guy working on my 140.

  The failed
component in the now-working amp was Q302, labeled 40410 in the
schematic.  On the component it reads:
 
"RCA 7-0012 HA 8142"
 
It's a PNP transistor with a heatsink attached.

does anyone know where would i look to find something like this?

thanks
chad

A "suspension" for my Acoustic 126 combo

feeds@yuku.com (headamp) — Tue, 13 Oct 2009 05:57:37 GMT

Just want to share this with you.
During the restoration of my beloved 126 (had to rewire two chokes), I discovered that it didn't sounded the same with and without the amp inside the cab...
I mean, the sound was brighter with slight parasite vibrations transmitted to the metal case of the amp itself when everything was put back together (amp in the cab)
Things were even worse when I tried to torque the 5 mounting screws a little more...
I decide to try something to...

Legend1965!

feeds@yuku.com (72jazz) — Sat, 10 Oct 2009 06:08:18 GMT

Hey Legend! I'd seen you post where you state; "I can fix any Acoustic problem you have" a few posts down from here where some gentleman is asking about a good source for parts...could you check my 320 post please and possibly direct me accordingly? Thank you, 72Jazz!

Need help with Acoustic 135

feeds@yuku.com (jeffv145) — Fri, 09 Oct 2009 13:49:31 GMT

I bought a vintage acoustic 135 guitar amp for 100$. I love the amp, it sounds great but I am having trouble with the Feedback. I am also using a Boss DS1 pedal and an 1994 ibanez talman (lipstick tube) guitar. Does anyone have any suggestions for this setup? I love the sound but the buzzing has got to go. When I stand the right way it is minimized, but I need to figure out what is making this horrible noise. I am sorta new to this so any advice would be great...

JV---

470 Footswitch project complete!

feeds@yuku.com (Delicious Bass) — Fri, 09 Oct 2009 12:26:31 GMT

Finally got a footswitch made for my 470. Maybe this could be helpful to Mr. Cheech?

I picked up a busted Marshall 5 button footswitch, took out the circuit board and momentary switches. Installed salvaged DPDT switches. Plugged the center hole with a metal hole plug from...

125 service manual?

feeds@yuku.com (Delicious Bass) — Wed, 07 Oct 2009 09:55:12 GMT

Hey all,

Just picked up a 125 for 50 bucks (non-functional but w/ good speakers and footswitch!). It's in good cosmetic shape but has some connection problems somewheres (lights are on, nobody's home). Anyone have the service manual to send? Thanks!

db

Problem with T bolts in 361 cab

feeds@yuku.com (ldolber) — Mon, 05 Oct 2009 19:31:01 GMT

Just restored a 360/361 acoustic bass amp. First attempt. Everything went perfect until I over tightened the side bolts and stripped 3 of the t bolts. There is currently no rattling and the rig plays perfectly. 7 of the 10 bolts are tight. The problem is if I have to take the cab apart. Any suggestions on getting the bolts out. All they do is spin with the t bolt. For now not a problem but later??

Acoustic 470 footswitch help

feeds@yuku.com (Uncle Cheech) — Mon, 05 Oct 2009 15:14:02 GMT

Hey guys, I'm looking for a little help in building my own footswitch for my 470. I have the schematics, wiring, enclosure but i need some info on the following:
- What rating/type of pushbutton switch is used
- What is a part # for the Jones plug. The one pictured on the site is different from the one in the schematic and I can't find one anywhere!

Any help would be greatly appreciated!

Thanks,
Uncle Cheech

370 help please

feeds@yuku.com (xdanx709) — Mon, 05 Oct 2009 05:25:02 GMT

I just buy a 370 and when i when to check it out before i payed for it the guy selling it had it running through a peavey 15' combo because he didnt have a cab. It sounded fine to me everything worked good. But when i got home and hooked it up to fender bassman 2x15 cabinet it sounded bad and would cut in and out. So i hooked it up to a 15' combo i have and it worked fine. Just want to know why it would work running into a combo and not a cab?