Dynaco Unofficial Home Page Frequently Asked Questions (FAQ)

Thanks for checking out the web site. I receive a huge amount of e-mail about the site and about Dynaco equipment. In order for me to proactively answer the most common questions and have more time to spend on updating the site itself (it's just a hobby, even though I take it seriously) I present the site FAQ. It is my hope that common questions can be dealt with quickly and accurately here, saving everyone some time. As questions occur which aren't yet answered on this page, I will endeavor to add them to the FAQ expediently.

Where can I find a shop that will repair my aging Dynaco gear?

There aren't many nationwide repair shops that deal with 40-year-old stereo equipment. Luckily, I have found some places that can handle Dynaco repairs (though typically not upgrades). They are:

Audio Clinic
905 Bonifant St.
Silver Spring, MD 20910
phone 301-587-0070
fax 301-587-3551

Circle Stereo
5555 N. Lamar BLVD Ste. L-127
Austin TX, 78751
phone (512) 454-8277

Electronic Service Lab
140 Scotch Rd
Trenton, NJ  08628
(609) 883-7555

Used Sound
31 Holland St
Davis Square
Somerville MA
(617) 625-7707

For mod kits and other upgrade options, Triode Electronics and Curcio Audio (see the links page) do some work, and sell upgrade parts for Tube gear. The bright side is that most good TV/radio repair shops (and even some guitar amplifier repair shops) should be able to fix the average Dynaco amplifier with the aid of a schematic and parts list. Heck, even the alert audiophile with some electronics background can probably work it out eventually. I provide a growing list of schematics to help with servicing of these units, and I will add to the list of reputable repair shops as they come to light. Don't hesitate to let me know if you hear of any.

Where can I find replacement (potentiometers, capacitors, knobs, etc.) for my Dynaco equipment?

There are two sides to this question. Generic parts like volume controls, resistors, capacitors, etc. are readily available if sometimes hard to locate exact values. Again, the links page may help here. However, Dynaco-specific parts like panel switches, knobs, transformers, and the like are very scarce today. Ebay is often the only place to look; happily there is a fair amount of Dynaco gear auctioned every day on their site. Knobs and the middle era bass/treble controls are just about unique; I know of no substitutes for the real things -- but I've found some in auctions and flea markets from time to time. Happy hunting!

Where can I find replacement tubes for my Dynaco equipment?

I'm not the tube expert, unfortunately. Tubes to fit the Dynaco power amps and tuners are becoming increasingly hard to find every year. Some aren't made any more and you'll have to scrounge for NOS parts or try to substitute. Check out Gary Kaufman's site link on the home page for much much more info on the tube gear. Again, Triode Electronics and Curcio Audio have some access to parts and even replacement/upgrade boards which obviate the need for exact replacement tubes. With flea markets charging upward of $100 per pair for even the small output tubes, I'm loath to recommend long-term maintenance plans for any of the tube gear; but then, I'm awfully pragmatic about my stereo system!

Where can I find replacement dial lamps for my Dynaco tuner?

At last, one that I can answer concisely. The "cartridge" lamps for FM-5 and AF-6 tuners were custom parts, but you can swap in a pair of Radio Shack fuse holders and inexpensive new cartridge bulbs for about $10. The "Stereo" and "Tuned" lamps were also custom units, and equally easy to replace. A blue LED and 600 ohm resistor (in series) will replace the existing bulb and restore proper Dynatune / muting to the tuner for about $5. There are more of these quick fixes, and I'll probably add detailed descriptions eventually; watch this space!

Where can I find replacement parts for my Dynaco speakers?

Check the Madisound and Morel links on my links page for a starter. They have some near-exact replacements and suitable upgrades for the 1960s/70s speakers which may enable you to restore them to full working condition at minimal cost. If your problem is merely a destroyed surround, they can be replaced at home using few tools, adding years of life to the speaker. I'll post some links to the repair-yourself speaker sites if there's more interest.

How can I fix my (ST-120, ST-70, PAM-1, ST-416)?

I wish I had time to research and write detailed troubleshooting manuals for all the Dynaco gear. If I have time, I'll try to answer specific questions about repair problems (assuming I have anything constructive to say; I haven't worked on very many of the Dynaco amps...). Check out my schematics; I have a growing list of solid-state gear on the site, and Gary Kaufman's site supports the tube grear pretty thoroughly. I would suggest that if you're motivated to try repairing your own component, you are half way there. The schematics and a voltmeter will solve many problems by simple comparison of channels, and an oscilloscope (mandatory if you really want to troubleshoot cleanly) will reveal a surprising amount about the unit's functioning. Do use proper safety techniques; if you're not sure what they are, you should take a community college or correspondence course on electronic repair before digging into ANY electronic equipment. It's fun, rewarding, and will increase your enjoyment of the newly repaired component!

Where can I buy used Dynaco equipment?

I probably sound like a broken record, but again I recommend Ebay for an active, if sometimes pricey, selection of Dyna gear. Sometimes you'll have to pay too much, sometimes you'll get a steal; but patience is often rewarded. If you're aware of electronics flea markets or hamfests in your area, give them a look. I've found nearly half of my vintage Dynaco components at flea markets, and they're sometimes cheap just because they're old or have a blown fuse. You probably won't score a pair of working ST-70 amps with matching PAM-1s for $35 like I did, but you would definitely be surprised at what does show up for reasonable prices.

Where is the schematic for the (PAM-1, FM-3, SCA-50, QD-1)?

I have schematics for nearly all the solid-state gear; all I'm lacking is time to get them all scanned and uploaded. Let me know your favorites, and I'll put them in the queue! I have not expended a lot of effort on getting the tube gear schematics online, because Gary Kaufman's site has them all and he's better equipped to deal with the tube questions and answers than I am.

What about the (PAS-4, CD player, A-150, surround speakers)?

This is a slightly touchy subject. My original intent in building this site was to celebrate the Dynaco company formed by David Hafler, and crewed by talented folks such as Ed Laurent, Wade Burns, Joe Sparacio, Jim Elliott, Sid Lidz, Bob Tucker, Bill Phillips, Harry Klaus, Erno Borbely, John Ferranti, Doug Hercus, Richard Pley, etc. etc. I wanted to provide detailed info on the equipment they designed, supported, and serviced, right through the end of the company in 1980. Even though Panor Corporation now owns the trademark, and is producing new equipment under the Dynaco brand, I hesitate to lump their work in with David Hafler's Dynaco. In my opinion (and I am gratified to share that opinion with several ex-Dynaco employees) the company that I loved and helped support with my purchases ended in 1980. The vision has been kept alive sufficiently by the folks at Sound Values/Sound Valves until 1991, and by hundreds of thousands of happy owners in the years since then. And of course, by the gracious help of several former Dynaco employees who took time to correct my errors, talk to me at length, and provide me with priceless information about the heyday of Dynaco. While I'm happy that the Dynaco brand lives on, I think I will leave it to others to chronicle Panor's progress, out of respect to David Hafler and his friends who made Dynaco the household word that it was from 1955 to 1980.

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This page created and maintained by Greg Dunn.
Copyright © 2002 Greg Dunn