Trouble with my Friedman tonight

I
Don O said:
I never understood that. If you design in a fuse cause you need to protect a circuit, make it serviceable and accessible without having to open the box. Here’s one on @Inspector #20 ’s 8200 Marshall head.

View attachment 86185
Click to expand...
I agree. My 1982 Marshall is Canadian version with heater fuses etc. While they rarely go, what a pain. Even has HT amd mains fuses inside as well as the one main outside.



 
Don O said:
I never understood that. If you design in a fuse cause you need to protect a circuit, make it serviceable and accessible without having to open the box. Here’s one on @Inspector #20 ’s 8200 Marshall head.

View attachment 86185
Click to expand...
It's because people put in oversized fuses..and they grab onto energized fuses and get shocked.

Ampeg used to put in an internal idiot fuse that would blow when an oversize fuse was installed externally.

But what it comes down to is that when the fuse blows, there's really something wrong.
Most People don't recognize this. They just stick in more fuses (or bigger fuses).
They don't look for a cause.
 
Last edited:
I opened the amp up looking for anything obvious. It's point-to-point handwired and very robust.
Connections are all solid; I wouldn't imagine something came loose or blew out.
[EDIT: No internal fuses.]

A pair of new EL84s should be arriving today or tomorrow.
Preamp tubes are vintage, black plate RCA and JAN Philips, but I think it's unlikely they're the problem.
I have a dozen or so NOS 12AX7s if necessary; bought a bunch before prices skyrocketed.
Looking forward to tube swapping this weekend.

Found a Traynor 1x12 with a Vintage 30 on Craigslist as a potential home cab; will be checking it out this eve.
Should sound pretty close to my regular V30-loaded 1x12 which stays at a friend's place with the other equipment.
 
Last edited:
67plexi said:
As far EL84 goes the longest lasting I have found are Sovtek EL84M Power Vacuum Tube
The day's of $2.20 each buying by the case are over and I tried the fake Golden Lion N709/El84 very disappointing they lack power.

View attachment 86397
Click to expand...
I have a line on some NOS Soviet-era Reflektor military grade 6P14Ps at a good price.
They have the reputation of being good sounding and about the sturdiest EL84 types ever made.
Only problem is, the seller is in Dnipro and I'm wary of prepaying for an order shipped from a war zone.

I've done a little reading out on the Web and apparently the PT20 has a reputation for burning through power tubes very fast.
Knowing that, I'm a little surprised mine lasted as long as they did.
Would love to get a really heavy duty set in there.

Yah, my impression is that the Gold Lions have received uniformly negative reviews.
 
Jethro Rocker said:
Is it the smaller DHX12? It has a removable panel on back to make or semi open back. Nice compact little cab!! Or could be one of the bigger ones.
Click to expand...
That's not the Traynor, it's a custom build I bought on Reverb years ago.
Extra tall & wide (much larger taller than the Traynor) but not as deep as a Marshall cab.
One piece back panel on it; I like the punchiness of a sealed cab myself.

Its size makes it sound a little deeper than most sealed 1x12s.
IMO it's actually closer to the tone of a 4x12 than the Marshall 1936 2x12 is, which is what I use with my rack rig these days.

My tone standard really is the Marshall 1960A 4x12 that I gigged from 1980 through the 90s, and should never have sold.
It was loaded with the G12-65s, and to this day that's the sound I hear in my head when I think ideal Celestion tone.

The aggressive voice of a Vintage 30 works quite well with the Friedman though, and stands well in a mix.
Also sounds very nice with my old Boogie Mk II which is pretty fat.

I did buy the Traynor cab I looked at - it's a YCX12, blue Tolex and a slightly curved front when seen from the side.
Quite compact: front-mounted V30 and completely sealed in back - the only screws visible are securing the jackplate.
If I ever get the two cabs in the same room I'll take a pic of them side by side.
 
eclecticsynergy said:
That's not the Traynor, it's a custom build I bought on Reverb years ago.
Extra tall & wide (much larger taller than the Traynor) but not as deep as a Marshall cab.
One piece back panel on it; I like the punchiness of a sealed cab myself.

Its size makes it sound a little deeper than most sealed 1x12s.
IMO it's actually closer to the tone of a 4x12 than the Marshall 1936 2x12 is, which is what I use with my rack rig these days.

My tone standard really is the Marshall 1960A 4x12 that I gigged from 1980 through the 90s, and should never have sold.
It was loaded with the G12-65s, and to this day that's the sound I hear in my head when I think ideal Celestion tone.

The aggressive voice of a Vintage 30 works quite well with the Friedman though, and stands well in a mix.
Also sounds very nice with my old Boogie Mk II which is pretty fat.

I did buy the Traynor cab I looked at - it's a YCX12, blue Tolex and a slightly curved front when seen from the side.
Quite compact: front-mounted V30 and completely sealed in back - the only screws visible are securing the jackplate.
If I ever get the two cabs in the same room I'll take a pic of them side by side.
Click to expand...
Oh yeah I knew that was not the Trayonr, I was asking which Traynor you were looking at as I have the one in question.
The YCX is a slightly larger cab than mine. That csutom one of yours sounds super nice!!!
 
Bit of an update: installed the new EL84s and they appeared to work okay; amp produced sound for a bit.
But when I checked it again later, nothing. And the power tubes appeared to be redplating.
I'm not up to checking transformer problems so I'll have to take it to someone.
 
eclecticsynergy said:
Bit of an update: installed the new EL84s and they appeared to work okay; amp produced sound for a bit.
But when I checked it again later, nothing. And the power tubes appeared to be redplating.
I'm not up to checking transformer problems so I'll have to take it to someone.
Click to expand...
Dang, another bummer!

Your amp is cathode biased. An improper bias can cause redplating. Maybe the shared power tubes cathode bias resistor and/or its paralleled electrolytic cap might have failed themselves, or their soldered connections to the circuit have been compromised. This would be easy to check by testing and measuring with a meter. You might have to disconnect one end of these components to measure accurately.

Hoping it's not your OT!
 
I looked at a gut shot of a PT. They are cathode biased with a 120R / 10watt resistor (higher wattage bias resistor= burns up the tubes before the resistor). I think Vox biased with a 130R which was toasty, Marshalls were 150R. Probably the reputation to chew up tubes may be quite real. Cathode bias at idle can be 100%, but I usually stay down @95%. Supposed pic of a PT gut shot below.

 
Last edited:
T-Rex said:
Supposed pic of a PT gut shot below.
Click to expand...
Yeah, this is the older version of the Pink Taco. The newer PT's have a more hybrid type of board but still with mostly the same components.

Encircled in red are the power tubes shared cathode bias resistor and its "filtering cap". Not sure if "filtering cap" is the proper term for this component...
ZldmpGn.jpg
 
You must log in or register to reply here.
Back
Top