favorite old gear to buy for parts

[Paul1453]

What are your favorite old pieces of gear to buy for parts cheap?

I have gotten some from old movie projectors, record players, stereos, and radios.  I'm looking to get some more power transformers, output transformers, pots, vintage tubes etc. from old gear for cheap.  What do you guys like salvaging parts from?  I haven't tried any old real to real recorders yet.  Like I said if I can get gear that has a usable power and output transformer in them for cheap any tubes etc are just a bonus.  What do you guys look for?

[TIMBO]

Hey mate, Valve ORGANS are the best source of parts and easy to convert to guitar use.

[Paul1453]

I definitely agree with that.  Unfortunately it seems everyone on Ebay knows that too and bids the stuff up to prices near what I could get new stuff for.   

[sluckey]

That's true. You just have to constantly watch and jump on a good deal immediately. In January I bought a Hammond AO-63 (see Timbo's pic above) for $19.

Juke box amps are good too, but there are plenty of JB restorers out there to compete with. And don't forget old PA amps.

[kagliostro]

Here (Italy) organ amps are difficult to be found (near impossible), Juke Box sometime are disposable but at prices that I consider high, evidently there is a large number of fans, with PA amps the things are better and sometime happens to find it at interesting prices


Franco

[Ed_Chambley]

Lately I have been running across a lot of tube console stereo's.  Picked up a zenith with 4 EL34, 2 OT's and a fine PT for $25 working.  I have been stopping at thrift stores out in the sticks.  I got a nice Stromburg Carlson PA with 2 6l6 for $80 after a tad of negotiation.  It was used in a Church and left in-place after they got a new system.  Looks brand new.

The old hammond tone cabinets go cheap and usually have a nice Alnico 12 in the top and a lof of nice iron if you just want parts.  Got one for free just to pick it up.

I go to hamfests sometimes.  Tubes and caps usually.

[Paul1453]

that's what I'm talking about ED!  Searched Craigslist and got an old Magnavox record player for $20.  Trying to find more deals like that and especially the gear that has the transformers we need for conversion.   

Are old reel to reel tape recorder/players another good source?  Do they usually have a useable OT?

[Toxophilite]

I agree, old organs, tone cabinets, film projectors, reel to reels, hifis etc. Basically anything that's not tooo fine, still usefull and or too cost prohibitive to repair. 
Just don't look in my area!!!

[Paul1453]

  Took another shot in the dark.  So far, all my other purchases along these lines have yielded at least 2-3x parts value of what I paid including shipping.  It's like my spidey sense starts tingling when I see a good BIN deal.  So I just bought this Japanese made R-R tape recorder for $26 including shipping.  If it's got a useable OT I've almost got 2x my costs right there.  I was looking through parts for R-R gear and noticed high watt power resistors and other various components that led me to believe it was worth a shot.  If its got a useable tube PS, I'll put another mark in my Good Deal column.  So, what do you all think, missed the mark or Bulls-eye?

[Toxophilite]

People also make those into simple tape echos.
Open it up and see, if It's got a little SE amp then have fun.

[John]

IIRC, that one will not have a PT, and the OT will be basically worthless (tiny). It uses the 50 and 35 heater volt tubes in it. However, it might have a Mullard tube in it which will pay you back. Most of the usable R-R's will cost $40 to ship, if the seller does a nice job packing.


I bought one just like it a year or so ago. The thing to look for in the pictures is the watts that it uses. If they have a PT it's usually 85/90 watts. Usable tubes also. The OT's in those things pick up PT hum like you wouldn't believe, so they have to be 3 inches at least apart. IMO, the little SE OT that Doug sells is well worth the $28, I think you get better tone with his. JUST my opinion.


Some of the PT's in them have 12 volt windings. I'm in the process of building a little amp now using that, and the 12AB5 it came with. I knocked together a circuit and liked it; it has a more Marshally/AC/DC type sound to it. Hope this helps!

[John]

http://www.ebay.com/itm/Early-WEBCOR-tape-recorder-model-210-1-with-microphone-/231729565114?hash=item35f4288dba:g:Ze0AAOSwjVVV5JVJ


http://www.ebay.com/itm/Vintage-Webcor-Reel-To-Reel-Tape-Recorder-TP-2005-1-/111802799948?hash=item1a07f7574c:g:gEcAAOSw3ydVpA-8




Those are the kind you want to watch for. The first one has a nice case that you can re use as well, and it gets lots of attention ;)

[Paul1453]

IIRC, that one will not have a PT, and the OT will be basically worthless (tiny). It uses the 50 and 35 heater volt tubes in it. However, it might have a Mullard tube in it which will pay you back. Most of the usable R-R's will cost $40 to ship, if the seller does a nice job packing.


I bought one just like it a year or so ago. The thing to look for in the pictures is the watts that it uses. If they have a PT it's usually 85/90 watts. Usable tubes also. The OT's in those things pick up PT hum like you wouldn't believe, so they have to be 3 inches at least apart. IMO, the little SE OT that Doug sells is well worth the $28, I think you get better tone with his. JUST my opinion.


Some of the PT's in them have 12 volt windings. I'm in the process of building a little amp now using that, and the 12AB5 it came with. I knocked together a circuit and liked it; it has a more Marshally/AC/DC type sound to it. Hope this helps!

OK, where were you 2 hrs ago?     Just kidding.  Yeah I got one of those little SE OTs and it's mounted on my breadboard now.  When you add in the shipping $12, it's about $40 for a low watt SE OT nevermind about a 15W or so PP OT.  I couldn't see a speaker or output jack in any of the crappy pictures.  I was hoping Hi-Fidelity markings meant more than 50C5 or 35W5 output tubes and a reasonable OT.  Well live and learn.  Maybe I'll still recoup my total investment in misc. parts.  I hope.  I'm sure my wife will say "What did you buy some more junk again?"  Then I'll say "But honey, the parts alone are worth more than I paid."  Then I'll hear "That's what you always say.  You're saving LOTS of money buying all this junk."     Later tonight, I'll post some pictures of my recent transformer lot I got for $25.50 including shipping.  It appears I got two unknown but good PTs, one blown PP OT, and two chokes one medium and one high watt.

[John]

I had went on a buying spree last winter, which is why I know that R-R. You might very well get lucky and get a nice tube out of it! I just forget anymore. The OT's in a lot of them are lay down type, but the PT are standups. The cases (the bigger ones) are quite nice plywood of some kind. I've made a couple little 5 watt combos with 8" speakers and they sound great.


I have a stack of them in the milkhouse waiting on me. The Wife is very proud.

[John]

Looked at my notes. If it's an ep-2400, you're good, should have a made in GB Mullard tube in it - 12ax7. But no PT I believe.


Notes say stay away from 2200 series, no usable tubes at all. Pass on any that say Air King. Statesman are also pretty small cabs, which makes me think no PT.


If you see an Ekotape, grab it. Nice iron.

[Paul1453]

Thanks John! 
That's the kind of info I was looking for and to share with the forum.  I've also got a notes list for Bell and Howell projectors.  Which models to take a closer look at and which to skip completely.   

B&H 16mm Model #'s:  142,179,185,202,285,302,385,399,535,630,641-644,8302(220V)
not a complete listing, but these are worth checking out.

[Paul1453]

Looked at my notes. If it's an ep-2400, you're good, should have a made in GB Mullard tube in it - 12ax7. But no PT I believe.


Notes say stay away from 2200 series, no usable tubes at all. Pass on any that say Air King. Statesman are also pretty small cabs, which makes me think no PT.


If you see an Ekotape, grab it. Nice iron.

Well you know what they say, "If at 1st you don't succeed, try try again."  With John's astute advice I'm pretty sure I did much better this time.  Bam, there it is Revere T-100.  That's the thing with Ebay auctions sometimes good stuff get's no attention and I can swoop in at the last second and pick it up for opening bid or just above that, and other times they bid the price to Crazytown.
That pretty much drains my weekly hobby budget, unless I actually manage to sell some things from my ever expanding junk pile.   

[Paul1453]

Looked at my notes. If it's an ep-2400, you're good, should have a made in GB Mullard tube in it - 12ax7. But no PT I believe.

If it's got a good Mullard 12AX7 in it I'll count it as a Good Deal, regardless of anything else.   

[Platefire]

I don't chase the flea markets, pawn shops, thrift shops and garage sales like I use to. However now that folks know I'm into that sort of thing, a lot of stuff just comes to me. I just threw away a big box of NOS tubes the other day. I paid $10 for them about 10 years ago. Problem was all that's left after I removed all the amp friendly tubes were all old tube TV tubes--nobody restores old Tube TV's. Worthless! I did pull all the tubes out of that box, before I threw it away, that AES is buying. I sent those to them and got a check from them the other day--$45

[kagliostro]

I purcased some reel to reel recorder and record player on the cheap, but I didn't consider it on the list of favorite old gear because they have small amp inside in the order of 2.5-5W, also sometime happens that PT is an autotransformer or is in one piece with the motor windings


Franco

[Zipslack]

Ditto on the R-to-R, but there are a few other flea market items to watch for -- intercom/callboxes and projectors.


My interesting cheap stuff:
* Voice of Music 722 R-to-R -> removed all the extra Mullard 12au7's and the motor, was left with a nice 6L6-based champ amp...no re-wiring needed.  Plug into one of the inputs and hit Record.  Also has speaker-outs.  Best $10 I ever spent.
* Sony R-R -> very clean and well-built unit; stereo = two SE amps using 6aq5 and 12ax7.  Just need another PT for the second SE. $14
* German made R-R -> similar to the Sony. $20
* Wooden hotel intercom callbox -> has a 2x6v6 amp with PT and OT.  Don't know why they had that much power in such a small box. $8
* Dukane projector/record player combo -> another 2x6V6 setup with transformers.  All the makings of a 5e3 for $12
* Bogen J15 PA -> almost an Ampeg Jet 12, old church PA. $30


Oh, don't forget that old radios are nice cabinets to build "living room" small amps into.

[Paul1453]

Zipslack,

Seems like R to R deals have been good to you!  These were my 1st ventures into R to R territory.  My Revere buy appears to have everything I need to make a Champ 5C, with some extra parts left over.   

[Paul1453]

Looked at my notes. If it's an ep-2400, you're good, should have a made in GB Mullard tube in it - 12ax7. But no PT I believe.


Notes say stay away from 2200 series, no usable tubes at all. Pass on any that say Air King. Statesman are also pretty small cabs, which makes me think no PT.


If you see an Ekotape, grab it. Nice iron.

You are correct, 2200 series no usable tubes or PT per say.  Maybe it can be slightly modified to make a small bedroom amp from the case, speaker, tubes and tiny OT it has in it.  I'll let you know if I come up with anything that remotely passes as a guitar amp so you can maybe try it on yours if you want.  I have a better feeling about the Revere.  I was able to locate a schematic showing a 6SJ7 and 6V6 with a real PT and hopefully good OT, before bidding on it.  I'm reasonable confident I can make a Champ 5C out of that one, with little to no added expense.  Or maybe something even better with another $20 worth of additional parts.

[HotBluePlates]

What are your favorite old pieces of gear to buy for parts cheap?

"Something that already looks like what you want to build."

Seriously. Individual resistors and caps are the cheap part of an amp build. Chassis, enclosure and speaker cost quite a bit more. The power and output transformers will be your most expensive parts, and they're typically sized to go with each other in the specific circuit f the item you're buying, with little wiggle-room to adapt them for other use. So your biggest cost also has the least opportunity to mold into something very-different.

For instance, I bought a Valve Jr at a pawn shop (cost $75 in like-new condition). Sounded okay stock, but sounded much better plugged into a 2x12 extension cab I had made, for use with any future builds (I've decided building heads to go with my common 2x12 is the way to go for me). There are plenty of "mods" on the internet for the Valve Jr, and maybe I'll tinker it at some point. But if I do, I'll only need to swap the p.c. board for something else and populate it (no added cost for speaker, enclosure, chassis, knobs, iron, etc).

At a minimum, I'd start with something was was audio gear in its former life. I'd also expect to keep the power supply and output section largely as-is. I've learned the hard way that buying non-audio tube gear to re-use in an audio amp only results in having a bunch of non-audio junk sitting around. When you're really skillful you can repurpose non-audio stuff, but by then you have all the tools, etc and you typically re-work something you already have or got for free.

[eleventeen]

I will agree with HBP to a major extent, but sometimes you get what are now expensive parts out of weird industrial gear.


For example, knobs are $2+ each. Buy something with 10 usable knobs for $10 and you are ahead of the game. Junk industrial gear very often yields up brackets and odd-shaped pieces of sheet metal and lockwashers and screws and single-post terminals. Once upon a time, all those things cost 25 cents each. Now, every tube socket is $2+.


Junk scopes, you have to get very cheap. There will lots of usable parts in those but tremendous numbers of non-usable parts. Lots and lots of 12AU7 tubes. 6DJ8 (much like a 12AX7 but with no 12 volt fil option and a different basing diagram. A big power transformer with half a dozen 6.3 volt windings but very low ampacity from 4 different B+ windings. Good, maybe, for a bench supply, not so good for an amp.


But there are also plenty of industrial devices that have 12AX7s and 5751s in them, as well.


A trashed hp 400 series VTVM (any of a dozen models they made) will yield: A Princeton-grade power trans, usually at least 1x, sometimes 2 qty 12AX7/5751, some nice binding posts. Even if they are smashed, there's $10-15 worth of amp-related parts.


I have some SKL audio filters that have 4-5 Telefunken 12AT7s.

[HotBluePlates]

I will agree with HBP to a major extent, but sometimes you get what are now expensive parts out of weird industrial gear.  ... A trashed hp 400 series VTVM (any of a dozen models they made) will yield: A Princeton-grade power trans, usually at least 1x, sometimes 2 qty 12AX7/5751, some nice binding posts. Even if they are smashed, there's $10-15 worth of amp-related parts. ...

True, except the HP 400_ A.C. VTVM's use all pentode preamp tubes... 6CB6's in the 400D, 6AK5's in the 400C, various metal octal tubes in the earlier models though sometimes a 6V6 in the power supply.

The 412A D.C. VTVM is the one with the 12AX7/5751. However, I'm very sentimental about those, given the excellent build quality and circuit function. I might have to hurt someone who ripped one apart, unless it was already beyond repair... 

But some of HP's other products have extremely high-quality parts. The problem is the types/values are suited to that circuit, and may be nothing like the values you typically see in an amp. I'd almost say the donor test equipment is your cheap way to repair other test equipment, rather than a cheap way to build an amp. I do agree that often, very high quality tubes were used in that old test gear.

[p2pAmps]

It's not a tube amp but ain't it great...

[Paul1453]

I will agree with HBP to a major extent, but sometimes you get what are now expensive parts out of weird industrial gear.


For example, knobs are $2+ each. Buy something with 10 usable knobs for $10 and you are ahead of the game. Junk industrial gear very often yields up brackets and odd-shaped pieces of sheet metal and lockwashers and screws and single-post terminals. Once upon a time, all those things cost 25 cents each. Now, every tube socket is $2+.

I'd have to admit this is my major source for these little do-dads.  I don't even count them as value, but they often keep me from running out to Lowe's and paying $2 for a dozen lock nuts.  Another part I like is the switch/pot combos found in a lot of this old gear.  Keeps me from having to find/make another hole for a switch to go in.  Does it usually look good using these odd parts in the amp?  No, but it keeps me on the path to making an amp.  Who really cares how the insides look when it's done if the amp sounds and plays great?  I'm not trying to sell these at boutique amp prices.  If I did a good job putting these parts together into something that will stand the test of time, it's unlikely anyone else will ever see them. 

[Paul1453]

It's not a tube amp but ain't it great...

I like it.  I kind of missed it when you put vintage classic gear that would be a sin to cannibalize in this parts thread.   

[p2pAmps]

Its a pretty rare tape echo that I would never dream of tearing apart.  I could build a very nice amp for what this thing is worth...

[Paul1453]

I looked real quick at 1st, still thinking about pots/knobs/do-dads.  Thought that was a scale or something on top before taking a closer look.  It still works I guess?

[eleventeen]

On the other hand, here's a fine piece of junk for parts. Looks like the seller got it for $6 at HIS garage sale. $50 delivered.


http://www.ebay.com/itm/Vintage-Flow-Corporation-Random-Signal-Voltmeter-Model-12A1-Powers-On/391302031838?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20131003132420%26meid%3Dbe6d5f64ec084efab05b02e745849bd3%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D231738048397





It would be $15 if you didn't have to ship it. At a hamfest this would be a sweet buy for $15.


HBP: It's like a rackmount 412 or 413 except specialty meter. There's a valid rackmount chassis there, good parts.

[Paul1453]

Anything old and heavy most people consider worthless junk and are more than happy to have you just take it away.  Heavy usually means transformers that may or may not work for us.  I'm always up for hauling away old heavy gear for someone.  Even if I just end up throwing it in my own trash at home after checking it out closely.   

[eleventeen]

That's really an excellent piece of tube junk. You could have 2-3-6 12AX7s there and the schemo might be on the web. And kind of interesting the mode of construction. I would have a hard time resisting that for $15 at a garage sale (eg; no shipping) 

[Toxophilite]

Nice echorec!!
It reminds of the echolettes I used to have and now kind of regret parting with.. but they had fixed tape speeds. That one is a pretty innovative design.

[P Batty]

I once got a Dynaco ST 70 along with a Dynaco Pre-amp and Tuner in a homemade console for $5. The thrift store didn't want it taking up space. One 7199 tube and some coupling caps later, I turned the amp for $300. I was really tempted to make it into a bass amp, but it was just too nice to butcher.

[Paul1453]

That's really an excellent piece of tube junk. You could have 2-3-6 12AX7s there and the schemo might be on the web. And kind of interesting the mode of construction. I would have a hard time resisting that for $15 at a garage sale (eg; no shipping)

Any idea what that hockey puck looking thing with the wires sticking out is?  $33 including shipping to my location is making my trigger finger itchy.   

[eleventeen]

I believe the thing is a flow meter, so it is possibly similar to a regulator except in reverse. Gas flows against a membrane, membrane pushes/rotates a rheostat, the deflection shows up in the front panel meter.  <--[wild a** guess only]


There's $50 worth of parts there. Or $40. PT looks excellent, plus its fairly clean. Worst thing that happens is you spend $10 too much. Very worth it, IMHO. And you could escape with a small cluster of 12AX7s, too. 

I am intrigued by the way it is built, it looks like in the chassis openings on the left you can see two turret boards.


Looks to me like a prebuilt AB673 or other board  could be swapped in there, wired up to the sockets, and this could be a rackmount amp with not much effort. Kewl.




There is obviously a seriously regulated power supply on the right and a nice line of tubes on the left.


Plus there's a very adapatable rackmount enclosure there, if that's of any interest. You could build a princeton or even a P reverb if you were willing to swing the can across the back. Somebody should buy that. 

[Paul1453]

Found out what the hockey puck is.  Couldn't find a schematic, but it obviously has a usable tube PT, and possibly a useable OT.  I like the separation of the PS from the signal tubes area, with lots of room to modify that area to install audio output tubes and a OT if necessary in a quiet shielded environment.  $32.64 delivered is likely cheaper than I can buy a PT for and if it's got a couple of 12AX7s it's definitely a good deal.  I've got an old rack mount Ibanez multi-effects box.  I'll need to get a rack now to mount these things in.  Thanks for the heads up!

Only other info I could find.  2-250K freq. range???  Could possibly have a seriously high quality OT.

It's mine.   

[eleventeen]

Well done. I don't think that is an OT, I think it is a choke; but that's a nice Triad choke. I love gear like this, all Allen-Bradley pots, good sockets. Fun.


You'll thank me if you get 4 - 93% 5751's in there.


And I really like the build quality, and, as you say the separate-area layout is nice. The chassis as a test bed looks terrific. Nice.

[Paul1453]

We'll see how it all shakes out.  I might owe you a couple of parts from my junk pile for just the shipping costs.    

You're probably right about that being a choke.  Looks like an extremely quiet PS would be necessary when measuring very small random signals.

[eleventeen]

Make sure you give us the tube report!

[PRR]

> Could possibly have a seriously high quality OT.

Doesn't have an OT. Just the meter.

Power supply appears to be 6L6 regulated.

[Paul1453]

Thanks for the info PRR.  I was wondering what that octal in the PS was.  I'm thinking that after removing the hockey puck that will be an ideal spot for a high quality OT.  This will hopefully be transformed into my never to be parted with rack mounted head unit.

[Paul1453]

Power supply appears to be 6L6 regulated.

Maybe PRR or someone else could help me understand the use of well known audio tubes as regulators in the PS.  I did a Google search but didn't find the kind of clear explanation I was looking for.  My adjustable HV bench supply uses 2 big audio tubes, some of the Google examples showed using 6au6,6bm8,12ax7,6v6,6l6 and others in the PS.  I have seen this in a few PS designs but not so much in the PS of the guitar amps we all love.  Does it have something to do with the frequency range/response of audio tubes, or is it more to do with their voltage amplification?  My understanding is that audio tubes are not designed to provide lots of current, so their use in a regulated PS has me a little puzzled.  Are they in there to help regulate the voltage, the current or both?     I truly appreciate your responses.   

On this purchase, a good 6L6 would add $10 to my parts value count.   

[PRR]

Audio amplifiers do not (almost never) need regulated voltage; there's better things to do with money.

Measurement equipment often includes regulation for consistent calibration.

The most popular series-pass tubes in regulators were 2A3 (fat audio triode) and when that went out of style, triode-strapped 6L6.

All the big audio Power tubes will pass considerable current. 6L6 with 250V on screen will max-out over 200mA.

The real issue is usually Dissipation. If you really asked a 6L6 to pass 200mA at 250V drop it would throw 50 Watts of heat, which is too-much for a 19W tube. Realistically you ask for <150mA at <150V drop. When that is not enough, find the big 'scope which had four or six 6550 bottles for pass elements.

A full tube regulator has two parts. A high-gain error amplifier (6AU6 is popular) and a big dumb pass tube (2A3, 6L6). Oh, and a glow-tube voltage reference.

In this case (RMS lab meter), unless I am missing something, there's no "big current". The meter is a LOW level (1uV) amplifier, normally to a rectifier and 0.2mA meter. This particular one "solves" a minor problem when reading RMS of a random waveform by heating a resistor and sensing the temperature rise. So it may be two high-gain amplifiers (one quite slow so low-current) plus under a Watt in the sense resistor. Still hard to see even 40mA in there.

The one octal tube in there (nice clamp) *may* be a steel 6L6. It could instead be a metal rectifier or the rare metal 6V6; or something else altogether. But you'd expect a rectifier to be with the PT and choke (or even selenium in this period).

Another possibility: getting CLEAN DC was a problem in the old days. Projector sound lamps were sometimes driven with DC rectified from a high-frequency oscillator. The metal octal could be doing something like this.

The power supply for this meter must be VERY clean, because it measures very LOW level hiss, and any hiss hum buzz or crap from the power supply contaminates the readings and makes the results dubious.

Designers breathed a big sigh of relief when clean transistors came out a few years after this beast. You could do all this with 1/10th the power, slightly better sensitivity, and a much smaller box.

[eleventeen]

Here http://www.vintage-radio.info/heathkit/ is a listing of Heathkit kit schematics. Look up a PS-3 or PS-4 supply.


These (and dozens of others) use a "6L6" as what's called the "pass element." The earlier PS-3 used 1619 tubes because there were billions of them available war surplus and silly cheap. 6L6 has never been cheap. The raw HV is wired to the plate, the + supply output is taken from the cathode. It's called the pass tube because every volt and amp the supply supplies passes through that tube. The output of the overall supply is fed to the grid of the pass element (most often through a gain stage) such that when the output rises, it slightly turns down the pass tube and the cathode voltage falls. This results in a regulated output.


If you Google "pentode voltage regulator" you'll find lots of info.


Probably, one of the tubes near the clamped-down 6L6 will be a gas regulator (OA2, OB2, 5651, these are voltage references.


Most likely, that 6L6, being a metal one, will not be of use to you.


There is questionable need to have a voltage regulator in an amp. I suppose on a max gourmet basis, you would have one. If you were making a super duper preamp, you might have a regulator, OTOH, preamp tubes use very little current and you have easily an 80 ma tranny, so that tranny would hardly know 3-4 preamp tubes were there. So why do you need regulation? If you were making a club amp....almost no club amp has a reg PS!

[eleventeen]

When I pointed out that that config of tubes was almost certainly a nice voltage regulator, I did not mean to imply it would be of any use to you! (Although it *could* power a preamp section, but again, why bother?) I would bet it prolly produces reg +250 volts, not +350, so it will likely not be useful.


That metal tube could be a 12A6 also. Very non useful. And yes, nice clamp!


What is kind of nice about this particular piece of junk is that if you want to ditch the reg PS, you should be able to just disconnect it, leave it in place as built and not torn apart, and do something else for your PS. It's a roomy chassis/enclosure.

[eleventeen]

Very good synopsis here: http://www.jacmusic.com/techcorner/SBENCH-PAGES/sbench/reg1.html

[Paul1453]

Probably, one of the tubes near the clamped-down 6L6 will be a gas regulator (OA2, OB2, 5651, these are voltage references.

Most likely, that 6L6, being a metal one, will not be of use to you.

I love the neon purple glow of the 0D3s in my bench supply!  Too bad I can't see them anymore with it all buttoned up.  It made me want to have some of those in a Hi-Fi amp or open type head where the tubes are all up front for everyone to see.   

Metal 6L6's no good as an audio output tube?  I looked at the tube data sheets and didn't notice any big differences from the 6L6GC, but they could have easily eluded my untrained eye.

I'll check out those resources you guys provided and try to get a deeper understanding.  Thanks! 
My Army network is not liking some of those links, I'll have to try again at home.