Heathkit W-6A

[bronco]

I just acquired a nice working pair of mostly original Heathkit W-6A 70 watt mono amps. Was wondering if anyone has any experience/recommendations/opinions on these?

 

[earthman]

Those are beautiful. :drool:

Sorry, it's all I got on these, never seen one in person.

 

[kvflyer]

Very nice!

 

[currituckco]

Wow, nice score. Is that a Cit I peeking out behind them, too?

 

[clydeselsor]

I would sell all of my gear for a set of those!

 

[NYListens]

I would sell all of my gear for a set of those!

I second that. (Except my speakers.)

 

[mech986]

Very Nice! Chicago Standard transformers I think, pretty beefy power transformer, 3 input driver tubes typically means basic williamson 2 stage input with 1 driver tube.

Need to find a good assembly manuals and schematic and look for any toxic or suspect parts - of course, before doing anything to them, especially if they are working, google and check around for what people think of them and any specific rebuilding or mod articles which have been published/recommended.

May have selenium rectifiers or old drying electrolytics. The FP Can type electrolytics may be an issue so get to know the valuess and start hunting for replacements or backups (or disconnect but leave present for the vintage look and add underchassis replacements.

Nice that the chassis looks pretty deep and tall so there should be room to work in. Does it have variable damping?

Please post some pics of the interior of the chassis.

Very nice score!

Regards,

Bart

 

[dnewma04]

You can make nice CII monoblocks out of them.

 

[ARRAY]

That is one very nice find. I'm certain those were Heathkits all time "best", and most powerful, tube amplifiers. They command significant coin on the used market.

 

[dnewma04]

I think the W7s were more powerful but less well regarded.

 

[DaWoofer]

Wow, haven't seen a set of those here in a while. I would also give up all my "stuff" for those. Although for sound quality I am quite happy with my Heathkit W-4's as they seem to have plenty of power at only 20 watts. But outdoors would be a hoot with those babies! Don't know what experience you have with tube equipment as I'm new myself to it but read, read, re-read all that you can find on them and you'll really enjoy the adventure. I am and I still have much more to do, tubes are fun. Good luck and we all look forward to hearing and being part of your new adventure.

 

[Steve O]

Very Nice! Chicago Standard transformers I think, pretty beefy power transformer, 3 input driver tubes typically means basic williamson 2 stage input with 1 driver tube.

Although the PT could be Chicago, if stock, the OPT is the mighty Peerless 16431. Arguably one of the best OPTs to ever show up in consumer grade equipment. Circuit topology is nominally a Williamson design but with a twist: CF driver stage. Traditional Williamson designs didn't use this. Also, DTN Williamson would probably argue strongly that any UL output stage immediately disqualifies a design as being a "Williamson".

 

[bronco]

Well, spent quite a bit of time today cleaning the outside of them. There is some nasty 50 yr old tape residue/glue on the tube covers I havent had much luck removing. Mineral spirits hasn't fazed it, any suggestions? I opened them up to take a peek, looks like some selenium to replace and probably at least the coupling caps if not the power caps. I would appreciate any suggestions on what to use to replace the selenium (part #845846) there is a 20mfd 350vt capacitor hooked to it. The gentleman I purchased these from had them hooked up and running(but they had not been run in quite a while), but I'm not sure if I should run them before replacing the capacitors?
Thanks
Matt

 

[Steve O]

I think the W7s were more powerful but less well regarded.

W7s were Heath's move into low cost big watts. The design resembles a Dyna MK2. They advertised them as a great bargain at only $1.00/watt since they were rated at 55W and cost only $54.95 in 1960.

The W6 was in a different league both in terms of design and power being rated at 70W and using a modified WIlliamson topology. It also cost almost exactly 2X the W7 at $109.95.

 

[dnewma04]

I knew they were less well liked, I just had the power mixed up, thought it was just the opposite.

 

[truep]

Try Goo gone or goof off for thr tape residue. (available at hardware stores) Test on s spot you can't see first to make sure you won't dammage the finish.

 

[bolly]

to remove old tape residue, I've had great success placing a damp piece of folded paper towel on the spot, then keep wetting it as it drys. Next morning you can use your fingernail, or a plastic card or similar to scrape it off. :thmbsp:

 

[jaymanaa]

Just for comaprison, here's a pair of W7-Ms patiently awaiting restoration.

 

[bronco]

Truly the tape residue from hell. Its probably 40 years old and crystallized to a hardness level rivaling a diamond! Oops remover didnt touch it either. Bead blasting them and repainting might be the only option here. I'm going to try acetone after testing it on an inconspicous spot inside the cage. After that---I think they are going to meet with some glass media!

 

[NYListens]

Truly the tape residue from hell. Its probably 40 years old and crystallized to a hardness level rivaling a diamond! Oops remover didnt touch it either. Bead blasting them and repainting might be the only option here. I'm going to try acetone after testing it on an inconspicous spot inside the cage. After that---I think they are going to meet with some glass media!

Have you tried goo gone or acetone? If you are going to repaint that, you may also try some paint remover. By the way, that looks like a candidate for chroming.