markmc@ncrcae.UUCP (Mark McCulley) (02/15/85)
> These >speakers have potentiometers to control a +/- 3dB boost/cut on both >the tweeter and midrange driver. I am considering replacing these with >fixed value resistors. Please mail (or post if you think it is of >a general interest) any suggestions or comments. BTW, the speakers >are Yamaha NS690. Last week, I removed the potentiometers and replaced them with discrete resistors. The upgrade was *considerable*. Those pots were FULL of 'grungeballs' :). After I made the mods and first listened to the system, I thought something was wrong - it was the next day before I realized that I had been missing a lot of the music. I don't know how much improvement could have been realized by just cleaning the wipers and leaving the pots in the circuit, probably a good deal, but I don't want to have to periodically clean them, and I don't use them anyway. This was certainly a bigger upgrade than any from equipment changes, and it was FREE (about an hours work with a soldering iron). I would certainly recommend that anyone having speakers with potentiometers investigate this modification. Hmmmm, I wonder about the pots on my preamp...? Mark ...decvax!mcnc!ncsu!ncrcae!markmc -----------------------------------------------------------------------------
ed@mtxinu.UUCP (Ed Gould) (02/26/85)
> Last week, I removed the potentiometers and replaced them with > discrete resistors. The upgrade was *considerable*. Those pots were > FULL of 'grungeballs' :). ... > ... Hmmmm, I wonder about the pots on my preamp...? It's easy to replace pots with "stepped" controls - just use a rotary multi-throw switch and a batch of resistors. You can replace the volume and balance controls with two stepped volume controls - if you want good matching between the channels, use precision resistors (use carbon resistors, not wire-wounds, as the extra inductance of the wire-wounds may not be good). I can dig out the values I've seen used for the resistors if anyone cares. (You nay also need an additional resistor on one channel for balance zeroing.) It's probably worth getting good quality switches (gold contacts, or some such) and make-before-break switches are safer and gentler to the ears (depending on the circuitry, they may be required). -- Ed Gould mt Xinu, 739 Allston Way, Berkeley, CA 94710 USA {ucbvax,decvax}!mtxinu!ed +1 415 644 0146
dw@rocksvax.UUCP (Don Wegeng) (02/26/85)
In regards to replacing the pots in your speakers with discrete resistors,
what value resistor did you use? How did you come up with this value?
Trial and error may work, but there's probably a better method that I
have not thought of.
Thanks,
/Don
--
"Do you always act normal, or are you just teasing me?"
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