Just noticed this post, November 14.

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Posted by Lew (A) on November 14, 2021 at 10:41:31

In Reply to: RE: I think I can help here.... posted by Atmer on July 11, 2021 at 08:15:57:

This explains my failure to follow up on SLOG.
It's great to know that a similar 1:90 audio transformer is available. I had forgotten the vendor, so thank you for providing his identifiers. So far as I recall, he was located in Perth, while Will lived in either Melbourne or Sydney, the opposite coast to Perth. Anyone intrepid enough to try this modification to an SL speaker should know that some who tried it back then, using the new production 1:90 transformers, did not like their results. Those guys eventually adopted the revised toroid purchased direct from SL. I never was able to figure out why the one or two guys I am thinking of were not happy, but I did determine for myself that phasing of the two transformers (the OEM bass transformer with the AU90) is very critical. If the two driving transformers are wired out of phase, the impedance goes down the toilet, like 1-2 ohms across the board, and the sound most likely would be awful. With any amplifier. The two transformers MUST be wired in phase with each other.

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Follow Ups Full Thread

Topic - Atma Question - Alsatian 08:59:43 04/14/21 (14)

RE: The impedance does not have to be flat. - Ralph 10:50:08 04/14/21 (13)

RE: The impedance does not have to be flat. - Simon Templar 23:43:09 04/30/21 (10)

RE: I'd use a set of Zeros - Ralph 09:51:59 05/03/21 (9)

RE: I'd use a set of Zeros - Simon Templar 14:34:44 05/04/21 (8)

RE: MA-1s are fine on Sound Labs. - Ralph 10:22:01 05/05/21 (7)

Fairly certain that mine predate that modification.... - Simon Templar 11:02:01 05/06/21 (6)

RE: older Sound Labs - Ralph 11:49:47 05/06/21 (5)

RE: older Sound Labs - Simon Templar 01:04:05 06/08/21 (4)

I think I can help here.... - Lew 09:05:40 07/06/21 (2)

RE: I think I can help here.... - Atmer 08:15:57 07/11/21 (1)

Just noticed this post, November 14. - Lew 10:41:31 11/14/21 (0)

RE: older Sound Labs - Ralph 09:17:20 06/08/21 (0)

Thanks Ralph... - Alsatian 11:07:45 04/15/21 (1)

RE: A lot of the LS35/a variants are 15-16 ohms. Get one of those and it will all be good nt - Ralph 12:08:13 04/15/21 (0)

Follow Ups

Just noticed this post, November 14. - Lew 10:41:31 11/14/21 (0)

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