My Heathkit AA-32 Integrated Amplifier

[Elite-ist]

I picked up this tube amplifier a little more than one week ago at my local mini flea market for $20. While at the store, I had it momentarily powered up for about half a minute to see if the tubes would light up. They all appeared to faintly glow, before I turned it off. It had a huge build-up of dust, and it needed a cosmetic cleaning. I replaced the overly large utility receptacle plug, which had been swapped in for the original, with a much smaller power plug.

It has seven tubes: 4 X ECL86 and 3 X 6EU7. Output is an advertised 12 wpc at 8 ohms and it has terminal connections for 4, 8, and 16 ohm speakers. If it indeed works, I'm going to use this amp to power a pair of 1960's British Leak Sandwhich speakers, which I picked up a month earlier at the same place.

http://i768.photobucket.com/albums/xx322/vintagevet/DSC04187.jpg

http://i768.photobucket.com/albums/xx322/vintagevet/DSC04188.jpg

http://i768.photobucket.com/albums/xx322/vintagevet/DSC04189.jpg

http://i768.photobucket.com/albums/xx322/vintagevet/DSC04190.jpg

http://i768.photobucket.com/albums/xx322/vintagevet/DSC04192.jpg

Nando.

[Dazen1]

If it indeed works, I'm going to use this amp to power a pair of 1960's British Leak Sandwhich speakers, which I picked up a month earlier at the same place.

Should be a good match Nando.

Leak (http://www.44bx.com/leak/) made some super stuff.

[Elite-ist]

Should be a good match Nando.

Leak (http://www.44bx.com/leak/) made some super stuff.

Hi Daren,

I'll try to get pictures posted of the Leaks, later on. These speakers were a technical marvel when they first came out in 1961. Do you know of anyone owning either the Leak Sandwhich speakers or Leak tube amps? Thanks for the link, too. I'm beginning to learn more about this old stuff, as I go. Some quite impressive components for the time.

Nando.

[Socal Sam]

Congrats Nando and good price. Looks like you have a solid state preamp, don't see enough tone tubes.

BTW, turning on a tube amp to see glow is a good idea but running it for any amount of time without speakers or load is not. The amp will overheat without load.

Have you tested with speakers? Keep us updated.

[Elite-ist]

Congrats Nando and good price. Looks like you have a solid state preamp, don't see enough tone tubes.

BTW, turning on a tube amp to see glow is a good idea but running it for any amount of time without speakers or load is not. The amp will overheat without load.

Have you tested with speakers? Keep us updated.

A question, Sam: by looking at the speaker terminals at the back of the amp chassis, the positive lead from the speaker is conected to the the terminal marked 16 ohm, and the negative lead from the speaker is connected to the terminal marked "C" as the common? The Leak speakers are 15 ohm.

Nando

[Socal Sam]

A question, Sam: by looking at the speaker terminals at the back of the amp chassis, the positive lead from the speaker is conected to the the terminal marked 16 ohm, and the negative lead from the speaker is connected to the terminal marked "C" as the common? The Leak speakers are 15 ohm.

Nando

Sounds right to me. You can verify by looking behind the speaker terminals. I'd power up with test speakers and hear what you get. Hope it doesn't hum!

[Elite-ist]

Sounds right to me. You can verify by looking behind the speaker terminals. I'd power up with test speakers and hear what you get. Hope it doesn't hum!

Thanks for the verification, Sam. I'm expecting no hum from this puppy- it's built in the USA.

Nando.

[Dazen1]

Hi Daren,

I'll try to get pictures posted of the Leaks, later on. These speakers were a technical marvel when they first came out in 1961. Do you know of anyone owning either the Leak Sandwhich speakers or Leak tube amps? Thanks for the link, too. I'm beginning to learn more about this old stuff, as I go. Some quite impressive components for the time.

Nando.

Nando,

Many years ago a colleague at work showed me his Sandwich speakers on the end of a home made amplifier (valves of course) and they sounded marvellous. The guy didn't own any records but was an avid listener of BBC Radio 3 which offers a steady diet of classical and opera.

[Elite-ist]

Thanks Daren: It makes the anticipation just that much better.

Nando.

[Big Kelv]

I used to have a early '70s Leak tuner which sounded fantastic, It won't be much use over here for much longer as the government has sold off most of the FM frequency range to DAB etc.

Must Grumble!

Regards, Kelv

[Elite-ist]

I used to have a early '70s Leak tuner which sounded fantastic, It won't be much use over here for much longer as the government has sold off most of the FM frequency range to DAB etc.

Must Grumble!

Regards, Kelv

Hi Kelv,

That's good to hear. I hardly expected to pick up a pair of vintage British speakers in my hometown. Do you know whether Leak products were sold in North America in the 60's? If not, someone took the trouble to pack them up on the trip over here.

Also, I received your tape, today. Thanks very much for that; I'm looking forward to hearing it.

Nando.

[Ricardus]

I have had an NOS AA-32 sitting in a closet for three years now, and finally am going to get to building it. I found it online, STILL SEALED in its original box. It must have been sitting in some back room for 40 years or more. Does anyone have any advice for me? I haven't taken a good look at the parts yet. Do you think any of the electrolytics should be replaced?

[Scorpion8]

Well, any caps that have not been used in those 40-plus years may have dried out and lost their value. You might think about using new, modern caps.

[Ricardus]

Yeah, I'm thinking Mundorf.

[Elite-ist]

Ricardus: Once you complete, or better yet, through the stages of the AA-32 kit build-up would you mind featuring your pictures and commentary? You will be powering your Energy Pro 22s, right?

Nando.

[Ricardus]

I'll do what I can as far as pics go. As I mentioned in an earlier post, I might have my friend Gene build it up for me (he offered). He's a brilliant tech. But I'll do what I can.

Yeah, I have a spare set of Pro 22's that I'm gonna power with this. I will be using a fairly common Sony consumer CD/DVD player as a source. I plan to use this in my mastering room, so that after I burn a master CD, we can listen on a system closer to what someone might have at home (even though most people are listening with ear-buds these days).

[Elite-ist]

I'll do what I can as far as pics go. As I mentioned in an earlier post, I might have my friend Gene build it up for me (he offered). He's a brilliant tech. But I'll do what I can.

Yeah, I have a spare set of Pro 22's that I'm gonna power with this. I will be using a fairly common Sony consumer CD/DVD player as a source. I plan to use this in my mastering room, so that after I burn a master CD, we can listen on a system closer to what someone might have at home (even though most people are listening with ear-buds these days).

Thanks, Ricardus! I'll try to post pictures of my system, later. I'm curious how this system will sound. It's comprised of the Heathkit AA-32 tube amplifier, Leak Sandwhich speakers, and Dual TG28 reel to reel deck.

Nando.

[Ricardus]

Actually, I couldn't find any good pictures of those speakers of yours. I would love to see a shot of those.

[Elite-ist]

I took pictures tonight, Ricardus. I'll post them in the "Speakers" sub-forum.

Nando.

[Mr_rye89]

Congrats Nando and good price. Looks like you have a solid state preamp, don't see enough tone tubes.

BTW, turning on a tube amp to see glow is a good idea but running it for any amount of time without speakers or load is not. The amp will overheat without load.

Have you tested with speakers? Keep us updated.

Turns out this amp is all tube except for the rectifier is silicon. the output tubes are ecl86/6gw8s which have the phase splitter/driver triodes in the same envelope. kinda like the 6bm8s in my house sitting amp *bigthumbup*

schematic here:
http://www.nijnkonijn.nl/machmat/schema/power/ppp/heatha32.gif

this amp looks nice and simple unlike the can of worms hh scott I worked on. btw are those mullards?

[Ricardus]

this amp looks nice and simple unlike the can of worms hh scott I worked on. btw are those mullards?

Yes, this amp originally came with Mullards. I can't wait to finish building the NOS kit that I found, to warm those Mullards up!