Tube finds

BlueMDPicker

Hell, even a blind hog finds an acorn every once in awhile.

I have a ton of vintage tone wheel organ and Leslie stuff, but never gave much thought to the tube compliments in it until I became interested in tube audio gear (again.)

Popped the cage on an old Organ Mate (circa early 60's) reverb unit this morning and found two Telefunken West Germany tubes - an ECC82 and an ECC83 - both mint with <> bases and all lettering intact. Plugged the ECC82 (12AU7) in a new preamp I'm breaking in (which, by the way, uses 2 x 12AU7 but does NOT require matched pairs) along with a 50's black plate RCA and it's sweet, with shimmering metal percussion, pin point imaging, and dead quiet!

That got me curious about the tube compliment of my Leslie 122, so next step was to pull the amp on it. Hmmm.. two RCA 7435 (12AU7A) ribbed plates, halo getters. What the hell, into the preamp they went. Fantastic bass punch and definition!

Next tried the Telefunken in the first gain stage and RCA 7435 in the second. The best of both tubes emerged - amazing! I feel like a kid with a new chemistry set on Christmas morning (BTW - that's even better than a fat kid with a cupcake)

More later... hi ho hi ho off to roll tubes I go.....

HBombToo

or an HBomb with a BEER:D

organ

Sounds great. Take good care of those Tele's. I bet they're worth well over $100ea especially in the condition you described. It's interesting how you prefferred the Telefunken in the first stage. I hear Tele's are more dry/analylical sounding, so that sound gets a slight boost of warmth from the RCA. Tube rolling is so much fun.

I found out something very interesting last year. When I first got into tubes, my mom told me that my grandpa used to sell Telefunken tube radios. That's so cool.

Here's somethin very funny I read on audioasylum. A guy asked what Telefunken means because it's German. A member replied saying it means "phone sex" as a joke LOL. Tele-funken = Phone sex ROTFLMAO:D.

Maurice

BlueMDPicker

Maurice,

Received a pair of EH gold pin ECC82's I'd ordered yesterday and got a chance to audition them a bit last night. My first impression was quite similar to the EH 6922's - where'd the bass dynamics go!? Within 45-60 minutes of play, it was back dramatically.

My wife was on a second floor landing, open to the listening area, when the EH's began to open up. She leaned over the railing between tracks of the album I was listening to and asked "I thought the new preamp didn't have a remote?" I responded "it doesn't, why?" She replied "did you get up and adjust the volume during that last song?" I responded "no, why do you ask?" She yelled down as the next track began "BASS!!"

The EH's internal build is strikingly similar to the vintage Telefunkens. Sonically I'd rate them initially as leaning toward clinically precise and lacking just a bit in mid-range liquidity. I haven't had a chance to roll a warmer sounding tube in with one of them, but that should be a nice mix. More later.

Mike

organ

Sounds super. I also used the EH ECC82 but they weren't gold pins. Very nice sounding tubes. My favorite was the Mullard ECC82. It's very cool how you got to hear the tubes breaking in. I've experienced this a few times with new tubes. You might want to give the Ei ECC82 Elites a try as well. The Elite version have gold pins. I was very impressed with their ECC83 which was a copy of the Telefunken smooth plate.

Can't wait to try out the EH 6922. The pre should arrive next week. I'm goig to try the JJ 6922 also. Do a search in the tube forum on audiosylum.com Tube rolling on that pre shouldn't be expensive because it's only using a single 6922. So I'm going to have a Sinle Ended Triode pre going into a push/pull triode amp. I'm so excited.

Maurice

BlueMDPicker

Hi Maurice,

I'll give the Ei Elites a listen, thanks for the tip. I've settled in with the Tele and a 50's black plate for awhile with my EE MiniMax. The EH ECC82, in tandem or mixed, just seems too thin in the depth of the soundstaging. Hard to explain, but easy to hear.

What new preamp do you have coming?

Mike

Edit - Just bought a pair of Ei's on the bay. More fun!

organ

Mike,
Golden Tube Audio SEP-1. I haven't heard a tube pre with my Dynakit in a long time since my ASL broke down.

Very cool. Let me know what you think of the Ei. Don't know if the 82's are a copy of Tele but I know for a fact the 83's are.

Maurice

BlueMDPicker

Originally posted by organ
Very cool. Let me know what you think of the Ei. Don't know if the 82's are a copy of Tele but I know for a fact the 83's are.

Maurice,

I received the Ei's today - nearly a carbon copy of my Tekefunken 82 both mechanically and sonically. Great build quality and out of the box exceptionally good sounding tubes. The only "problem" I had was nearly pissing my pants at power-up! Man, did these babies flash! I'd read about European type tubes doing that but never witnessed it (and wasn't ready for it.)

Mike

madmax

Ha Ha... A few of mine do that too. I remember the feeling.
madmax

BlueMDPicker

Perhaps European is a pun?

organ

That's great to hear. So looks like current production is really approaching NOS quality. Some current production is just as good as NOS, IMO. I think the "NOS is better" crowd are just snobs. These are the people who won't even touch the new stuff. One thing I really liked about my Ei is the super low noise level. That tube was almost dead quiet!

Mine had a big flash too but I already knew about it from reading tube forums before purcasing the tube:).

Just wait until you get your Dyna. You're going to have a fu*king blast rolling EL34 tubes. My JJ E34L are just starting to break in and they sound very different now than they were straight out of the box. I'm guessing they've had around 30hrs. Every brand of current production EL34 tube sound very different from one another. The JJ have WONDERFUL sound. Very pleasing highs, tubey bass and very realistic mids. The tube bloom is on full force. I really like the mids because it's not "refined" nor "aggressive". Sounds like live music. I've never heard live music have that "refined" sound audiophiles lust after. Too refined and it sounds fake to my ears. The SED EL34 is an example of this.

Maurice

BlueMDPicker

Hi Maurice,

Got the ST-70 up and running yesterday. WOW! Put the Mullards away to start and dropped a matched quad of the JJ/Tesla EL34's in. I ran it for about 8 hours with the PAS-3X up front and driving a set of SDA-2A's - sounded pretty damn good. Then, I put the EE MiniMax CDP and pre up front driving a pair of Monitor 11's - pure effing magic! 25-35 watts of tube amplification blows 100-200 of SS clear out of the water! I'll try the Mullards sometime if I can force myself to turn the amp off long enough

Mike

organ

Awesome! Sounds like you're really enjoying the amp. Did you get the JJ EL34 or E34L? The E34L is suppose to be a better tube with 20% more headroom with better bass and dynamics. Mine took around 25hrs to break in. More warmth and dynamics.

How steady is your bias? It will fluctuate with your home's line voltage. Best thing to do is to measure your bias every 20 mins or so and when you find out during which time it's at its peak, set it to around 1.4V. Make sure it never goes over 1.56V or the plates will glow and the tubes will die.

You're absolutely right about tube watts blowing away SS watts. Mine blows away 120W of NAD power:D.

Keep me posted as you roll EL34 tubes. Another one you can try out is the Electro Harmonix 6CA7 which can be used in place of EL34 tubes. I purchase my tubes from www.thetubestore.com Some EL34's take a lot of time to break in. My EL34EH took 100's of hours. The ones I've tried are JJ E34L, EL34EH, Shuguang EL34-B, SED EL34, Svetlana EL34 and EH 6CA7. All have their own unique sound. I'm sure you'll find your favorite. So far my fav's are the JJ E34L and EL34EH.

Any plans on mods or restoration? You can visit www.dynaco-doctor.com or www.triodeel.com for parts, mods, upgrades. I'm going to upgrade the power supply caps next. I hear the larger capacitance upgrade really gives the amp a boost in power. I think dynaco-doctor have upgrades for your PAS as well.

Isn't it amazing how good these old amps can sound? When you're all set don't forget to strap that amp in triode;). Enjoy the new toy.

Maurice

BlueMDPicker

Hi Maurice,

I got the blue glass E34Ls you turned me on to from Tube Depot. They sound great and have approx. 12 hours on them so far. I haven't even tried the Mullard EL34s yet.

What I have in mind is to put a nice hardwood cap on the chassis front and leave everything stock in place - swapping the Stereo/Mono switch with the On/Off and using a long throw toggle in front. I also want to leave the bias test points up front with some nice single pin sockets through the front cap. Might also move the inputs to the back, haven't decided yet. On the back, I'm thinking of a similar cap set out approx. 1" with wood rails to give me room to add modern binding posts and an IEC socket without modifying the chassis at all. I also have this wild idea about building a lexan tube cage with plenty of vent slots (if it will take the heat, have to reserch it) and etch/engrave the Dynaco ST-70 logo on the front then illuminate the lexan with some blue LED's. The chassis top and transformer bells are pretty clean, so I don't think I'll mess with them. I'd also like to find a chrome cover for the PC board. That should keep me busy, eh?

The bias has been holding steady for me, so no issues there (and no plate glow!)

Yes, you said it - dynamics and bass are fantastic! I can just imagine the thrill someone had 40 years ago firing-up their newly built kit and experiencing SQ of this caliber.

Mike

BlueMDPicker

Here's a quick pic of it pumping out some Son Seals (with the Mullards finally in place):

fireshoes

Man I need to get me one of those. It just looks bad ****.

organ

WHOA! Very cool. That amp is in excellent condition. Careful when working under the hood. The old wiring and socket connections are crusty and can easily snap. Looks like you're going to be very busy working on this amp. So I'm guessing you'll be stripping her down for the rebuild? You have some nice plans but there's a few you should leave the way they are. The power switch and rca ins. If you bring the power switch to the front, you'll have to run a wire there which will sit very close to the rca ins and there's a very good chance that they'll pick up too much noise from the power line. The rca ins should be left on the front. It was designed like this to keep the small signal path as short as possible to the 7199 driver board and to keep it away from the transformers. Modify the amp only if you're sure you won't be selling it in the future (I'm sure you won't:D) because its value will continue to drop as you move it farther away from stock.

Your plan for the wooden panels and cage sounds very ineresting. I see that you really like blue:). Keep us posted on your work with this amp. I'll post a pic of mine when I get the chance.

I see you've got the Mullards in there. How does it sound compared to the JJ. I hear the JJ sound closest to Mullard. Nice choice in IC btw. I'm also using a pair of AQ Diamondback from source to pre and XLO from pre to amp.

Maurice

BlueMDPicker

Originally posted by organ
Modify the amp only if you're sure you won't be selling it in the future (I'm sure you won't:D) because its value will continue to drop as you move it farther away from stock.

The more play time I get on this amp, the less inclined I am to do too much to it. It sounds fine as is. And, I think it looks great as well. I may just clean it a bit more, change out the octal sockets, replace the power switch (it's seen its better days), and replace the speaker terminal strip and input RCA's with NOS - available from soundvalves on eBay:

They also have NOS hardware packs for the ST-70 and I'm gong to grab one of those.

In time, I think I'll replace the PC board - but, keep it stock with the 7199's. The board traces are brittle and I've already point-to-point wired one broken solder pad (my first trouble shooting adventure with a vintage amp.)

Addition: I got to do a couple of hours of critical listening this morning. The JJ/Tesla E34L's are a much more all around musical tube in this ST-70 than the Mullards.

The one caveat to that statement is that I don't know how closely matched the Mullards are (no way to test them) and the JJ's are a perfectly matched quad.

The JJ's have a tighter bass with marvelous extension, they obviously have greater headroom and mu (takes approx. 20% less preamp signal strength to drive to same amplitude), and mids/highs are so lifelike (metal precussion shimmers and decays like a live session) that it gives you goosebumps.

I had to back the bias pots down quite a bit from what the Mullards needed.

And to think these tubes probably aren't even broken in yet. Pretty cool!

Mike

organ

Sounds like a great plan. I'm still doing a lot of thinking about the driver board. By this summer I will get a new 7199 board or the upgrade board using three 6922 tubes from dynaco-doctor.com I've been doing a lot of reading about the upgrade board and everyone who is using it say it's a much better sounding board than the 7199. It keeps the warmth and smoothness of the original but have better HF and LF extension. Another reason for me wanting the upgrade board is because the price of NOS 7199 is getting out of hand and they're hard to find. The current production Sovtek is garbage and I will only use RCA black plates.

Glad to hear the JJ sounds that good compared to Mullards. But like you said, maybe they weren't matched very well or they could be weak. I agree about the JJ sounding very lifelike. I love mine. I really enjoy the EH as well. They have more HF extension and is a more lively sounding tube. Yours should start to break in by now. They should sound warmer, smoother and bass should be more powerful.

Maurice

madmax

Organ,
If you start using 6922's make sure you try the Bugle Boy tubes, Ampex. They have a solid bass which will make you shiver. Big, full and ballsey. You've never heard such a sound.
madmax

madmax

Not 6922's but this is what they look like.

F1nut

How's about these tubes!?!

organ

Madmax,
Thanks for the heads up on the BB. If I get the upgrade board on my amp, I'll need 3 of them and I'm sure that's going to cost a lot of $$$. So I think I'll look for a single one and use it in my pre which accepts both 6DJ8 and 6922. Looks like the BB's are pretty rare. Amperex are easy to find but not BB's.

F1,
Those are nice looking amps. Big tubes too:).

Maurice

RuSsMaN

I've got some JAN, made in Holland NOS 6922 (Amperex), and plenty of old, good Bugle Boy's too. You just let me know when you need them.

I sent a single Amperex Bugle Boy, a Mullard, a Sovtek, a JAN (Phillips) with the SEP-1 to you, and I think it has a GE installed currently.

6DJ8 and 6922 are fully compatible and interchangeable. Like I need to tell you guys, but '6922' is simply the mil-spec designation for a 6DJ8, EXACTLY the same tube structure and pinout.

Blue MD, those Mullards all tested good, short of one. It was a quad of Sylvania, but one tube tested below discard. That's why I put a stock 'Dynaco' labled Mullard in it's place, which tested VERY close to the remaining Sylvanias. Took about 2hrs to test a whole box of tubes, to find the best match for your amp.

Cheers,
Russ

organ

Hey Russ,
Received the pre yesterday. :eek:I AM SHOCKED!!!!:eek: The sound is absolutely amazing! After looking at the pic MM posted, the amperex you sent me does indeed look the same internally. The box only said Amperex and the label on the tube have been rubbed off, that's why I thought it was a regular Amperex. I found the JAN a little bright but it could be the Klipsch or it needs to break in. I'm going to break it in when I have more time. I haven't tried the Amperex yet. So far my fav is the GE black glass and Mullard. The GE have amazing mids and highs but lacks deep bass. I have the Mullard in there right now. Thanks a lot for everything. My system kicks serious **** now!

Maurice

organ

Here she is in her new home sitting beside the Dyna...

RuSsMaN

The writing was rubbed off? Man, I probably sent you the wrong one. I had a NICE one set aside for you, with good lettering and the tube/bugel on it.

I'll have a look.

Cheers,
Russ

organ

Cool. Anyway, the "A" is still on the glass:) and the metal plate below the getter have the two square bumps just like on the pic mm posted but I'm still not sure if it's BB. Man, I can't believe how good that pre sounds. The transparency of my system is on another level now.

Maurice