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previous: Matt You know how you think you understa... -- 5/20/2003 4:16 PM

Re: RS-Deluxe OT question

5/20/2003 8:08 PM
sr	Re: RS-Deluxe OT question you do use all 3 windings in all 3 load setups with the RS. The 'myth' is just that the best way to maintain consistant leakage inductance (eg: high freq response) is to use the whole winding, and that still holds true TTBOMK. Traditional tapped OT's have (theoretically at least!) different freq response at each tap, with 4 being the worst, 16 the best. Can you hear it? I dunno. Also it is considered good practice to take your -fb tap from the same tap the speaker is on (not critical, but nice) and again, it's often on the highest tap. The original JTM45 amps which used the RS Spares OT were hardwired for 16 ohms (had no switch.. very Henry Ford!) I'm sure folks were buggering around with bad load imps prior to this though.. (wonder what a Champ sounds like through a 12", or a 4x12? or .. You're basically "not using" half the windings when going 8 ohm. How do you figure? All 3 windings are hooked up no matter which imp you choose. Whether it's 4, 7 or 15 they are all hooked up. Terminals are: A - F. 3 Ohm: A-C, B-E, D-F terminals are A & F 7 Ohm: A-B-D C-E terminals are E & F 15 Ohm: C-D E-F terminals are A & B

5/20/2003 8:08 PM

Re: RS-Deluxe OT question

you *do* use all 3 windings in all 3 load setups with the RS. The 'myth' is just that the best way to maintain consistant leakage inductance (eg: high freq response) is to use the whole winding, and that still holds true TTBOMK. Traditional tapped OT's have (theoretically at least!) different freq response at each tap, with 4 being the worst, 16 the best. Can you hear it? I dunno.

Also it is considered good practice to take your -fb tap from the same tap the speaker is on (not critical, but nice) and again, it's often on the highest tap.
The original JTM45 amps which used the RS Spares OT were hardwired for 16 ohms (had no switch.. very Henry Ford!) I'm sure folks were buggering around with bad load imps prior to this though.. (wonder what a Champ sounds like through a 12", or a 4x12? or ..

You're basically "not using" half the windings when going 8 ohm.

How do you figure? All 3 windings are hooked up no matter which imp you choose. Whether it's 4, 7 or 15 they are all hooked up.

Terminals are: A - F.
3 Ohm: A-C, B-E, D-F terminals are A & F
7 Ohm: A-B-D C-E terminals are E & F
15 Ohm: C-D E-F terminals are A & B