Lafayette Donor Iron?

[Geezer]

I picked up a freebie in a garage sale grab bag--a very early Lafayette integrated amp, model Stereo 224. The tube complement is a 5AR5 rectifier, 4 6GW8 outputs, and 3 12AX7s. The PT is thoughtfully labelled: Model TP15, on one side it has 270/270V 190mA taps, and beneath that is a 5V, 1.9A single and a terminal labelled E. On the opposite side, above the line inputs are 6.3/6.3 1.7A taps, and beneath that a terminal labelled 2A. The line inputs are labelled 115V and 0, I'm not sure what that 2A terminal is about. I'm not at all savvy in interpreting these old markings.

Moving onto the OPTs, they've got no designation numbers and have square metal covers, 2 1/2" x 2 1/2" by 2 3/4" tall.

I dismantled the amp reclining on my couch with the TV on, which was a mistake--when I took the amp from the garage I apparently deprived a mouse family of their condo, and when the bottom plate came off the fallout was pretty gross. It's a new couch, too. However I removed the transformer covers and the innards are intact and clean. All the transformers have paper between the winding layers.

I think that this iron should be well-suited to Baby Blue, but I need some input. Is anyone familiar with vintage Lafayette gear and are these transformers good quality? The price was right (free), but if they're poor quality I'd prefer spending money on known-good OPTs.

Also, given the quad 6GW8/triple 12AX7 tube complement, can it be determined if the OPTs are in the same ballpark as the Z565? I need to learn how to test and rate xformers myself and I apologize for being lazy, it's just something I've never done.

I've searched far and wide and can't find anything about this amp and its output rating. If anyone knows of a schematic it'd be useful--once again, it's a Lafayette Stereo 224. From what I gather, the 6GW8 was the poor man's EL84 and was used in mass-market consumer equipment.

Thanks for any tips, and god bless you for lending a helping hand to a transformer-challenged individual.

[TerrySmith]

Hi Geezer,
I took an old Heathkit AA-32, (6GW8 PP out) stripped everything but the iron, and built a nice little amp using SV-83's and 12AX7's on the front. It really sounded nice! :sign7:

If no UL taps, you will need to rig up a screen circuit on your PS. :computer:

[EWBrown]

The 6GW8 (ECL86) is a bit more power-capable than the 6BM8 (ECL82), 12W as opposed to 8 W for a PP circuit. From what I could glean from other tube data websites, the typical OPT impedance for these is from 8.2 to 9 K P-P.

My own SWAG is that the power handling of the Lafayette OPTs is not up to a full 17 watts per channel without some sacrifices in frequency response, but using the original 270-0-270 power iron with a DIY35 board and EL84s or SV83s, should work out nicely, keeping the power levels between 10 to 12 watts per channel.

RCA tube data here:

http://www.pmillett.addr.com/tubedata/H ... _ECL86.PDF

The OPTs should be OK for triode mode or SV83s, as these are lower output power configurations anyway. 35 mA bias seems to be the norm here.

The price was right, and all those mouse "leavings" were included at no extra cost!


/ed B in NH

[tubes4hifi]

I've owned 2 of the Lafayette 224, it's an excellent amp, I actually preferred it to the Dynaco SCA35.
Makes an excellent donor, or just freshen it up a little and keep it stock!
I believe there are photos somewhere in this forum of a DIY ST35 I built with it, using a gold anodized custom top plate.
Roy
www.tubes4hifi.com

[EWBrown]

More lafayette tube amps on e-bay:

http://cgi6.ebay.com/ws/eBayISAPI.dll?V ... =3&rows=50

/ed b