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I have inherited a Silvertone Console Model 2080C from my mother (she cherished it because it belonged to her parents). I do know the last time it was powered up by someone just a few months ago, it did work, including the EM84 magic eye.
I am not interested in using the "phonograph". The amp section has 2 - EL84/6BQ5, 2 - 12AX7 and rectifier EZ81. (I have woodworking experience and could mod 2 cabinets from original.)
The Tuner section uses 1 -6BE6, 1-6BA6, 3-6AU6, 1- 6AL5 and the magic eye.
I have all of the original paperwork and schematics and diagrams--a definite benefit. But can't post here yet because they are PDF.
I have wanted a tube project that I could learn from without killing myself. (I have listened to many, many nice rigs at the RMAF --ten years in a row). I also have a Silvertone guitar and guitar AMP, so this would be a nice addition to my family.
It says 120 watts on the back of the cabinet. Sure seems high to me. Any ideas appreciated.
* I am a complete newb to tubes, other than replacing them, and the most audio wiring I have done was on some New Vifa Tower crossovers. But am a DIY person from household electrical, woodworking, restoring vintage machinery- to currently replacing head gaskets on Subie, so I am confident in my current DIY skills.
Follow Ups:
BTW, I think the speakers are in fine shape dual "full range" 12" with a 4" in the middle. Can't see any brand, so probably Silvertones.
(I have replaced surrounds a few times) The original speaker in my ST 1482 guitar amp is still working fine as well, and they are both probably early/mid '60.
Holy smokes. Just googled that 1482 and see prices from 3 to 650. When I bought years ago (to mate with my ST axe) my wife laughed at it. Looks like my $37 (plus 2 new tubes) was a sound purchase.
Edits: 05/14/16
The old console amps have skyrocketed in price over the last few years. Many of them sound like garbage, but there are a lot more newbies who want to try them than there are survivors. This has pushed market prices up to the point that these skeletons may now be the worst bang for your buck possible.
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Buy Chinese. Bury freedom.
Great starter project- and should sound very nice-
You may need to head over to Radio Road for help on the tuner - or find a Tech to re-align it- but the rest is relatively straightforward.
Have fun!
Happy Listening
Perfect first tube project! Probably good for 4-5 watts output per channel. Just keep everything as is for now - use the original speakers, etc.
First step is to replace all of the electrolytic and tubular capacitors with fresh modern versions. Then see how it sounds to you. Note that many of the consoles have multiple speakers per channel and use a simple non-polarized electrolytic cap as a crossover. Replace those, too.
Torn speaker cone? Repair with rubber cement and paper from a tea bag.
Yeah, don't kill yourself with high voltage! Do take the advice others have given you and read up on safety practices, basic soldering skills, basic tube and electronic theory. But don't be afraid to jump in and start your journey. There is nothing in there that can't be fixed later if you screw it up he first time.
Once you do the initial "re-cap" and have it working, then you can either enjoy it as a job well done and move to the next project -or- start modifying. Either way, welcome to the crazy club!
If you have hi efficiency speakers and the console is not in great shape you can just rebuild the amp which will make a surprisingly good sounding single ended amplifier. regards, Dak
I am not interested in using the "phonograph".
That's just as well. The piezoelectric cartridge present will damage valuable LPs.
You should find cables from the TT to the rest of the circuitry that are equipped with RCA plugs. "Yank" those plugs and use the jacks freed up for a modern, digital, source. As piezoelectric carts. are "self equalizing" and high O/P, all may be well. However, a substantial chance of a "hair trigger" volume control does exist. If that happens, resistive voltage dividers installed across the jack terminals dispose of the problem.
Use AA Email to PM me. After a message exchange, I'll convert the schematics from PDF to a graphic form that can be uploaded. IrfanView plus GhostScript handles that chore. An alternative way of obtaining the schematics in graphic file format is to use the Windows Snipping tool, while the PDF has been opened with suitable reader software.
Eli D.
I would urge you to pick up a used copy of the ARRL Handbook from the '50s or '60s. This is the ham radio handbook, and it includes exactly what you need to get started. It's not an audio book, but there are sections that discuss tube basics, construction techniques, and most importantly - safety.
As for the console, you didn't say whether it's stereo. Looking at the tube lineup, I'm guessing it's a stereo amplifier, stereo phono and mono tuner. If that's correct, it will output about 4W/ch using the 6BQ5s in single-ended mode. Like someone else said, the tag on the back represents power consumption from the line, not audio power.
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Buy Chinese. Bury freedom.
Any circuit using 2 - EL84/6BQ5, 2 - 12AX7 and EZ81 has potential for good sound.
It may need capacitors replaced, and I would add an AC line fuse. A lot of those had no fuse.
I'm sure 120 watts id power consumption, nor output. Output is probably around 12 watts.
Yes, 12 watts much more like it. Thanks for all the detailed feedback, and the book reference --much appreciated.I don't know what folks here call such original docs, but in woodworking we call it "dirty paper' or shorter "porn" . The parts list in the tech manual has all of the descriptive details/values for all components and the tuner alignment procedure.(12 pages total)
This is my first time to post pics, so here is the Stereo Amp schematic, radio schematic, wiring board radio chassis, amp tube index.
Edits: 05/12/16 05/12/16 05/12/16
I was wrong about the connectors. They seem to be "proprietary".
You have something to work with. The 6CA4/EZ81 rectifier heads the list, in its general category. How far to go is your call. The reverb portion is pretty hokey. However, eliminating that and the very dubious tone controls is easy enough. L_RD knows, plenty of simple, well functioning, SE 6BQ5 circuits are available. If tone controls are a "must", good stuff is available that will put the reverb bottle to good use.
While the tuner section is strictly mono, an important feature is present. Notice the multiplex (MPX) O/P jack. You can construct a MPX decoder and enjoy stereo FM. DIYer extraordinaire S. Bench provides the uploaded schematic.
Speaking of the tuner, a ticking/toxic time bomb, in the form of a selenium rectifier, is present. That part MUST go. Replace the 1/2 wave selenium rectifier with a full wave 4X silicon diode bridge. Forward drop in selenium is greater than that in silicon. Even if they were "good", which they are definitely not, the 150 WVDC tuner filter electrolytic caps. need to be replaced by parts rated for at least 200 WVDC. As modern 'lytics are much more volumetrically efficient than the circa 1960 stuff, fit will not be a problem.
Eli D.
Eli --thank you so much.
No need for the reverb. I never use tone controls, even when I have them. I had noticed that MPX decoder note in the tech manual, so thanks for the details on that.
I do listen to FM because nearby is FM90 college and commercial free. (Also, it is important that I keep the tuning eye going as I remember it from childhood--mesmerizing.)
All of you have given me great leads and ideas.
It speaks highly of the members here.
Cheers
Edits: 05/12/16
"No need for the reverb. I never use tone controls, even when I have them."
Good man! Simplify, simplify, simplify. ;> )
Again I ask, how far do you want to go? For instance, console amps frequently have undersized O/P transformers, which leads to poor bass extension. Within the 5 WPC capability of SE 6BQ5s, better performance can be realized by installing Edcor GXSE15-8-5K O/P "iron". Global negative feedback (GNFB) will ensure "full" bandwidth is obtained. A 15 W. part is chosen to ensure that core saturation (very, very, bad) from a deep bass error correction signal does not occur. BTW, the Edcor "iron" would allow for experimentation with both full pentode and ultra-linear (UL) mode O/P tubes.
Eli D.
How far to go? Good question--not thinking that far ahead yet--- but speaking of bass extension, your suggestions are right on. #1, I am a bass guitar player (for therapy, not pro)and #2, I fall asleep most nights to either E Power Briggs or Gould, Bach preludes for organ. So bass is near and dear and --the Edcor seems a reasonable upgrade.
(Before I get a start on this I have a couple components in my SS system to get repaired)
Have another tube component. Will email you on it.
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