Stromberg Carlson

[Eilati]

I have been offered this amp from a local bay area person.

Stromberg Carlson ASR-433 stereo integrated
tube amp?
It has 2 pairs of EL84s for outputs, 2 12AX7s, 2 6AV6s and 2 6U8As in the front end.
It needs the 4 section power supply cap replaced, and would be a good restoration project.
It's heavy, 25lbs, the transformers are excellent quality. I checked them and they measure properly.

I have no experience w/tube amps, is this a good amp?
What does "the 4 section power supply cap replaced" mean?
What is it worth?

HELP
Eilati:dunno: :dunno: :dunno: :dunno: :dunno: :dunno: :confused:

[Celt]

The 4-section cap is a electrolytic that is in effect, four capacitors in one container sharing the same ground lead. (May be a metal can on the chassis) No big deal if you can't find an identical match, just replace them with four seperate caps with the same values. Good luck with the project! Bet it will make a fine sounding amp.

[Thatch_Ear]

You can also use separate capacitors under the chassis if you can't find a "can" that is the same. Snap in caps can be glued on with a dab of silicone and the others have longer leads and are easy to solder in. Many leave the old can in place and making use of the resisters that are in between sections use smaller new caps of the same value. That way you will still keep the original look.
Stromberg Carlson made some very good gear and I think made the best coax speakers during that time.

[NOSValves]

Replacing the can is a simple task as mentioned above. Its easily done with new cans today rather then the separate approach. JJ Telsa is making a 4 section 500V and also CE manufacturing is making them although on the pricey side compared to the JJ clamp mount. Stromberg carlson made some great amps and this one should sound great once gone through I bet it needs a bit more then just the can if its still 100% stock though.

Craig

[Chad Hauris]

Also don't forget to replace the paper caps. The old paper caps might work after a fashion, but you will get better sound quality, less distortion, and greater reliability/safety by replacing them along with the electrolytic. Also if leaving the old can in place and putting new electrolytics under the chassis, make sure the old can cap is electrically disconnected from the circuits.

[Thatch_Ear]

Yes, I wasn't real clear on that. When you have the amp upside down and are looking at the wiring there are usually large resisters between the legs of the can. The voltage gets lowered as it goes through the filtering of the AC ripple. Highest voltage powers the output transformers, lowest usually to the mini tubes in the signal amplification part of the amp. You have to get those resisters back in their proper places of the circuit to make sure the voltages going out are correct.
Caps were one of the most expensive parts of amps and most were made with minimum capasitance. Since I can buy lots of things local I replace every electrolitic, the coupling caps unless they are oils (them if they are leaking) and I tend to bump things up a tad. I will often use .47 instead of .33 for instance. If in doubt keep things the same and especially in the power supply section and around the power tubes to keep the voltage capability high. You don't need 600VDC caps on your 12AX7s but having that safety factor where the voltage is the highest is good to have.
Bumping up the uF in the can a bit is OK but do not have more than 40 uF in the 1st stage because your rectifier won't like it. And speaking of rectifiers you need to look for a selinium rectifier and if it is there replace it with a silicone diode. Selenium will break down just sitting on the shelf and since they are not made any more you don't want to put another in there. Look for something that has heat sink looking wafers.
If you don't have a variac, buy one.

[Eilati]

Thanks all for all the advice. I have never done this before so I will need all the help I can get. I will be picking this amp up in the next week or so. From the spec's above, is it worth $60.00?
Like I said, this will be my first venture into the TUBE world and I am a "Babe in the woods".
Thanks again
Eilati

[Chad Hauris]

60.00 sounds a little high to me...it might be fair, however, if there are no other alternatives. I have found amps like this at the flea market for $5.00 and $10.00, also they can sometimes be found in thrift stores. You may wish to check out your local secondhand stores/flea markets, particularly out away from large cities, as this stuff is junk to some people and they just want to get rid of it.

[NOSValves]

In my opinion in this day and age of eBay chances of scoring a amp like this for $10 is highly unlikely and even $60 is a stretch ! Check eBay and I bet you find these go for well over $100 all the time. At $60 you can't lose.

Craig

[Thatch_Ear]

If the tubes are good they are worth $60. A pair of good output transformers cost more than $60. If you lose out it won't kill you and if you get it up and running like new, that is worth more than money.

[spkrman57]

Stromberg Carlson made some good stuff, my favorite is a rare ASP422 with 6DY7(???) outputs for 22 watts/chnl. The amp does not sound like you would think though. Very sweet. I think it is worth it for you to get yours!!!
Ron

[Eilati]

Oh excuse me this is not an E-Bay item, I won an auction on e-bay and the seller contacted me privately to ask if I want this amp. I said yes!!!!!!!!!!!!!!!!!!!:yippy: :bigok: :bigok: :yikes: :yikes: :thmbsp:

[Eilati]

Shalom Y'all
Here is a pic of the Stromberg Carlson amp. More on the way.
What do you think now. I am curious as I am buying it one way or the other.
Eilati

[VinylHanger]

The front looks exactly like the one I have, but I have 7027A outputs in mine, for 30 watts per channel. It is a very nice looking unit and even needign some major tlc it is a keeper. I paid 10 bucks for mine with the matching tuner in the case. But this is a rare find around here these days. Good luck and the repair work shouldn't be too hard.

[GordonW]

Man, that looks like the later model of the amp I have, the ASR-333. Also uses EL84 outputs, but a different pre-driver complement (no 12AX7s, same otherwise).

GREAT sounding amp. Used it to drive JBL L77s, impressed the hell out of a bunch of people until the amp went down (suspect it's he power supply cap in this one that died, like yours).

Regards,
Gordon.

[NOSValves]

Here is the one I have here. Its a neat little 2 section setup you can remove the amplifier and use it with a modern preamp. But really it does darn good as is. uses 7189's for output tubes for about 18 WPC.

the rest of the tubes are

1 - 5AR4 rectifier

2- 7199 driver/phase splitter Amplifier section

4 - 12AX7's 2 preamp and 2 phone section


http://mywebpages.comcast.net/craigostby/StrombergCalrson.jpg