One that got away

[gui_tarzan]

I stopped at an estate sale yesterday in the Detroit area and noticed a couple of old microphones on the table. The gal said they were her dads, and he used them with an old RtR system that her brother was trying to get to work again.

I asked if she had any more vintage equipment and she said they had an amp that had sold earlier, and she said after they left she felt like maybe she sold it too cheap. I asked what it was, and she said there was no name badge on it, but one person commented that it was a Fender. She said it had a tan covering on it and was also her dads, and was very very old.

So of course I asked how much it went for, and she said they had put $60 on it because they didn't know what it was at the time. So now I'm thinking... very very old (50's/60's time frame), probably a Fender, probably a tweed, yeah, they sold it way too cheap but someone got a good deal on it.

And of course I was there too late. *sigh*

[TUBEDUDE]

Kinda sad really, 10 years ago reading that title I'd have thought a woman, now the first thing I think is amp or guitar.

[gui_tarzan]

LOL!

Actually, my wife and I have been married almost 31 years (in August) but I know what you mean.

[Leo_Gnardo]

Sooo..... what about the mics?

Tales from the old engineers: "back in the early 60's studios were throwing U-47's & similar into the trash because those new transistor mics were so much better." Smart engineers went dumpster diving or bought 'em for less than a penny on the dollar what they go for now.

And some of the early tube tape recorders had amazingly good sounding preamps: Roberts, Rheem, Viking, Voice-of-Music, Webcor, Ampex. I have a Crown tape pre tucked away, gotta build a power supply for it. Many years ago I built a supply for a studio that had 2, they sounded so good had to get one for myself.

Garage sale season's on, keep some cash ready & eyes open.

[Long Distance Call]

Leo_Gnardo,

I also have a pair of Vacuum tube Crown mic pres from an old tape recorder with consecutive serial numbers with no power supply. Would you have any schematics, design requirements, or any suggestions where to find this type of info? I would love to get these things running.

Any help or advice would be very appreciated.

Thanks,
LDC

[Leo_Gnardo]

Leo_Gnardo,

I also have a pair of Vacuum tube Crown mic pres from an old tape recorder with consecutive serial numbers with no power supply. Would you have any schematics, design requirements, or any suggestions where to find this type of info? I would love to get these things running.

Any help or advice would be very appreciated.

Thanks,
LDC

It was a while back @ 20 years. There's what, a 6V6 and a couple of small tubes in each pre, a 12AX7, 12AT7 and 6AX8. For use as a mic/line preamp only I left out the 6AX8 and 6V6. I think I took a WAG and selected a Hammond PT probably 269EX with 2.5A at 6.3V and slugged together a quick silicon rectified hi voltage section with a 2-stage filter, about 275V DC, ran the power supply to the Crown pre's with octal plug.

What's interesting about the Crown is the eq section in feedback loop on the final 12AT7 triode. Sounded mighty Pultec-like.

If you leave in the 6V6 and 6AX8, select a PT with some more filament and hi voltage current.

[Long Distance Call]

Leo_Gnardo,
Thank you for the information, it's very helpful, definitely gives me a starting point.

Would there happen to be a schematic available for the preamp? It would be great to have one to double check what I have now with with how it's supposed to be, just in case there have been any modification through the years.

Thanks again for your help,
LDC