Altec 15095A, any good way to utilize this as a direct box?

Ok, so I bought a box of tubes unseen at an estate sale. Mostly television stuff, but there was an Altec 15095A in the bottom.

Any chance of making a "flavorful" direct box out of this thing?

Do-able? Stupid? Put it up on Ebay?

I'm no transformer guru (way, way, far from it) and a little guidance would be much appreciated!

That's a 15K:600/150 line transformer.

It'd make a fine output transformer for a DI, but the best approach would be to use a JFET or triode amplifier to drive it. The primary impedance is probably too low to use as a passive DI.

It'd be perfect to use for the output of a preamp like my "One-Bottle" pre. Of course, the pre could double as a DI if you included a high-Z input jack.

Or you could turn it around on eBay for some quick cash. Audiophiles love 'em, they use them backwards as step-ups for MC phono catridges.

That was used for the o/p trafo on the Altec 1566a mic pre among other things (1567a mixer...).
...which reminds me of some long term procrastination on a particular project of mine...

Wow, they are going on evilbay for a high of $76 each now. Avg is about $50.

Oh, and I think the 4722 is the one that is favored for MC step-up. When I bought a pair of each of these, I remember paying more for the green ones... :green: :green: :green: :green: :green: :green:

Holy crap! I've been holding on to a few 15095s I scavenged years ago. I guess it's time to dump 'em before the economy finally collapses and people don't have money to spare for stupid shit :grin:

Shame that I *really* don't wanna deal with eBay...

As for 4722s: I have a pair, NOS, I offered on the Black Market but there were no takers:

http://www.groupdiy.com/index.php?topic=19550

15095's sound very nice, extremely excellent bass and rolled off top:

i have two that i plan on using as output tx for the hamptone tube mic pre from the tapeop article. should be fun.

now with that scope image what would it look like if they didn't have excellent bass response? softer triangle peaks? what does the sine wave tell you?

thanks

I have two that are going on the outputs of Dave's 6SN7 mic preamp design.

When did I design a 6SN7 mic pre--or was that some other Dave?

That Altec is the most common xfmr on ebay, so don't get your panties in a bunch.

Hey, if something that cost me $0 is now worth $50-$75, I'm gonna be psyched about it whether you like it or not. And I don't wear panties, Chief.

[quote author="NewYorkDave"]When did I design a 6SN7 mic pre--or was that some other Dave?[/quote]

You drew it. Raf built it. Image is gone now.

CLICK ME

Oh, I forgot about that one. It was just a quickie, not optimized and never breadboarded (by me).

[quote author="NewYorkDave"]Oh, I forgot about that one. It was just a quickie.[/quote]

In another context on Valentine's Day that would be a really bad thing to say... :roll:

[quote author="NewYorkDave"]I don't wear panties.... It was just a quickie...[/quote]

Maybe it's time for a mis-quoting thread. :razz:

[quote author="CJ"]On Valentine's Day, I got a bunch of panties! It was just a quickie, not optimized. Image is gone now...[/quote]

[quote author="Analog Packrat"]I'm gonna be psycho about it whether you like it or not![/quote]

Howz that for misquotes? :sam:

Image is gone now.

Click to expand...

I found it. I've made a nice clean re-draw and added a high-Z input jack.

LINK

Thanks for that, Dave. I've got scads of 6SN7's laying about so that looks like as good a use as any. :thumb:

Scads of 6SN7s, you say? You could also build a decimal accumulator for a computer :wink:

In the course of working on my tube compressor, I came up with a super-simple but effective one-tube line amp, 6SN7 (or its mini equivalent, 6CG7) working push-pull into a 15KCT:600 or 20KCT:600 output xfmr. If you use an input transformer with an identical ratio, you have a line amp with 20dB gain, low distortion, +24dBM or greater maximum output, no coupling caps and no -FB... advantages, I suppose, for those what have a phobia 'bout such things. It's a conventional circuit but works well; I'll draw it up if I find the time. This is getting off the topic of the 15095A, so I'll post it elsewhere if I do.

[quote author="NewYorkDave"]

Image is gone now.

Click to expand...

I found it. I've made a nice clean re-draw and added a high-Z input jack.

LINK[/quote]

Nice.