markmc@ncrcae.UUCP (Mark McCulley) (02/05/85)
I'm thinking about modifying my speakers and would like to hear some feedback from anyone that has had success (or failure) with this before. I'm not going to do anything 'drastic' like redesign the crossovers yet, just upgrade components for now. What I plan to do now is rewire with Kimber (sp?) cable, replace the capacitors in the crossovers with some high grade polypropylenes, maybe try bypassing the caps with .01 uf's, and put in some bigger binding posts. 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. Mark ...decvax!mcnc!ncsu!ncrcae!markmc -----------------------------------------------------------------------------
rfg@hound.UUCP (R.GRANTGES) (02/07/85)
[] Everything I have read on the net and elsewhere suggests that the improvements you are contemplating cannot hurt and may help. Why don't you let us all know how it works out. BTW, what speakers are involved? There are other things you could try, some of which could have adverse effects. If you have a bass reflex design spkr you could check and adjust, if necessary, the port tuning. If you have an "acoustic suspension" design (Edgar Villchur be praised!) You could try adding some more "acoustic absorber" material. I don't think either of these could get you into trouble. I especially like your proposal to eliminate the pots. They are a more or less reliable source of trouble, trouble, trouble. Whenever I visit someone who owns AR speakers, I go over and "tweak" the pots to get the tweeters going again. THey are always open and the owners never seem to notice it. ...Sigh. I have to use a step ladder on my own ...Sigh. -- "It's the thought, if any, that counts!" Dick Grantges hound!rfg
cdl@mplvax.UUCP (Carl Lowenstein) (02/08/85)
Actually on 'tweaking' the pots in AR-3 speakers. Every month or two
I think my ears have gone out again, and go exercise the pots. Does
anyone have the recipe for disassembling the back of the speaker box
where the pots live? I haven't seen the inside of an AR-3 since I watched
Eddie Villchur and friends running response curves on some prototypes
20 or more years ago.
--
carl lowenstein marine physical lab u.c. san diego
{ihnp4|decvax|akgua|dcdwest|ucbvax} !sdcsvax!mplvax!cdlherbie@watdcsu.UUCP (Herb Chong [DCS]) (02/09/85)
In article <2104@ncrcae.UUCP> markmc@ncrcae.UUCP (Mark McCulley) writes: > > I'm thinking about modifying my speakers and would like to hear >some feedback from anyone that has had success (or failure) with this >before. I'm not going to do anything 'drastic' like redesign the >crossovers yet, just upgrade components for now. What I plan to do >now is rewire with Kimber (sp?) cable, replace the capacitors in >the crossovers with some high grade polypropylenes, maybe try bypassing >the caps with .01 uf's, and put in some bigger binding posts. 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. > > Mark > ...decvax!mcnc!ncsu!ncrcae!markmc > >----------------------------------------------------------------------------- i own a pair of B&W DM7 Mk2's and i have modified my speakers by rewiring(using Fulton Brown) and changing the input connector board. i have not touched my crossover network because there is also a complete electronic protection circuit builtin. i may do so some day, but since i have only two electrolytic capacitors in my network (the rest are polypropylene), it's not a major change. the other thing that i did was apply silicone rubber to all joints to ensure they were properly sealed. also, you may consider adding bracing to the cabinet. the net gain is greater speaker efficiency in the lower registers. other changes are not so apparent, but slightly better midrange clarity was also noticed in my speakers. i have disassembled a pair of Yamaha NS1000M's and the crossover network contains all polypropylene capacitors and 16Ga wire. since the NS690's are next down, i would expect the wire to be pretty good and you may not notice as much difference as i did. the original wiring in my DM7's was 20Ga. Herb Chong... I'm user-friendly -- I don't byte, I nybble.... UUCP: {decvax|utzoo|ihnp4|allegra|clyde}!watmath!water!watdcsu!herbie CSNET: herbie%watdcsu@waterloo.csnet ARPA: herbie%watdcsu%waterloo.csnet@csnet-relay.arpa NETNORTH, BITNET, EARN: herbie@watdcs, herbie@watdcsu