Design Acoustics PS-10 Tweeter Issues

[silkrd]

So I just got a pair of these the other day. Were working great! Tweeter level switch on the left was a little flaky, but otherwise just fine.

Have them going this morning and the tweeter on the left just... cuts out. Dead. :c

Any idea what it might be and if it'd be easily fixable? I want to assume it's the crossover, but then again, the mid and woofer are just fine...

 

[jackwoz]

clean the tweeter level switch w/contact cleaner .

 

[GD70]

Great speakers!

If the pot cleaning doesn't work, pull the tweeter and put a meter to it and see if there's continuity, or connect the speaker wires from your amp to the tweeter and play it at very low volume to see if it produces sound.

Glenn

 

[stickman]

If the tweeter does turn out to be problematic, fortunately for you there are usually original replacements available on FleaBay from people parting out PS-10's at somewhat reasonable prices.

I agree with the preceeding posts that the issue is probably a corroded tweeter level control potentiometer. Get that cleaned up or replaced and you should be good to go.

 

[GoRNR]

If the tweeter does turn out to be problematic, fortunately for you there are usually original replacements available on FleaBay from people parting out PS-10's at somewhat reasonable prices.

I agree with the preceeding posts that the issue is probably a corroded tweeter level control potentiometer. Get that cleaned up or replaced and you should be good to go.

^^^ +1 stickman probably has it right on. Although the potentiometer DA used for the tweeter level appears pretty robust, I've read on this board and elsewhere the potentiometer is prone to intermittent operation and requires cleaning. From my own experience cleaning did NOT work. I put an ohmmeter on the pot and rather than a smooth resistance change when moving the control, the resistance was jumping and as I approached 1/8 turn from minimum resistance on the pot, the pot would go open. Even after a repeated cleaning/treatment with Deoxit. The resistance measurements exactly coincided with what I was hearing. PE has a 15 Watt version of the potentiometer that is a very close match. Unfortunately for me, the tweeter was still dull/distant sounding with a new potentiometer. I finally went to the auction site (as suggested above) and bought a good used one. That fixed my final issue. I concur with GD70 too-- they are quite good sounding speakers for what they are. That small footprint is a big plus for locating them. Most original PS-10's will need to have the woofers refoamed by now too. The typical foam rot issue. The replacement surrounds are widely available. Carry on....

BTW- I did a recap on a pair of PS-10 crossovers. Just for S's&G's I measured the capacitance and ESR values on the original caps. All the original caps measured within tolerance for capacitance and the ESR was well under .5 ohms also. The crossover capacitors may be the last place to do your troubleshooting based on my experience. Just FYI.

 

[silkrd]

Wonderful! I'll go and pick up some contact cleaner. I'm assuming the switch will be accessible once the woofer is removed?

Fortunately these have already been refoamed and are otherwise in great condition. Just need to get that other tweeter working.

 

[GoRNR]

silkrd- So we were discussing a level control earlier in the thread and then your post just above states "switch". The PS-10A's do in fact use a toggle switch that I believe is on the rear panel for the tweeter level. The early or original PS-10's have an actual pot for variable tweeter level located on the front panel. If you have the tweeter level control pot, yes, remove the woofer and possibly move some fiber fill out of the way. The level switch on the other hand is on the rear panel. This too would be accessible once the woofer is removed-- or you may be able to remove the entire rear panel. I'm not familiar with the PS-10A's, so not absolutely sure the entire rear panel will come out easily.

 

[skiesrblue]

On mine One of thewire lead tabs broke off of the LPAD. I got a replacement from Parts Express that worked just spiffy.

 

[GoRNR]

On mine One of thewire lead tabs broke off of the LPAD. I got a replacement from Parts Express that worked just spiffy.

+1 Been there, done that (with PE replacement pot)! In my case tabs OK, but LPAD was definitely OTL. To OP: cleaning potentiometer is worth the effort-- but if that doesn't work.....

 

[silkrd]

silkrd- So we were discussing a level control earlier in the thread and then your post just above states "switch". The PS-10A's do in fact use a toggle switch that I believe is on the rear panel for the tweeter level. The early or original PS-10's have an actual pot for variable tweeter level located on the front panel. If you have the tweeter level control pot, yes, remove the woofer and possibly move some fiber fill out of the way. The level switch on the other hand is on the rear panel. This too would be accessible once the woofer is removed-- or you may be able to remove the entire rear panel. I'm not familiar with the PS-10A's, so not absolutely sure the entire rear panel will come out easily.

This is the version of the PS-10s with the toggle switch on the back as opposed to the front-mounted pot; sorry for not clarifying.

The panel on the back was indeed removable. On the downside, I'm left with this glued-together monstrosity:

http://i.imgur.com/ftDBMdn.jpg

http://i.imgur.com/wg5zBPt.jpg

Switch looks pretty sealed to me, anyway. :\ Any suggestions short of hoping cleaner can get in from around the top?

I'm definitely feeling it's the switch; very stiff and grindy in movement unlike the other which is smooth and effortless.

 

[philnext]

^^^ +1 stickman probably has it right on. Although the potentiometer DA used for the tweeter level appears pretty robust, I've read on this board and elsewhere the potentiometer is prone to intermittent operation and requires cleaning. From my own experience cleaning did

^^^ +1 stickman probably has it right on. Although the potentiometer DA used for the tweeter level appears pretty robust, I've read on this board and elsewhere the potentiometer is prone to intermittent operation and requires cleaning. From my own experience cleaning did NOT work. I put an ohmmeter on the pot and rather than a smooth resistance change when moving the control, the resistance was jumping and as I approached 1/8 turn from minimum resistance on the pot, the pot would go open. Even after a repeated cleaning/treatment with Deoxit. The resistance measurements exactly coincided with what I was hearing. PE has a 15 Watt version of the potentiometer that is a very close match. Unfortunately for me, the tweeter was still dull/distant sounding with a new potentiometer. I finally went to the auction site (as suggested above) and bought a good used one. That fixed my final issue. I concur with GD70 too-- they are quite good sounding speakers for what they are. That small footprint is a big plus for locating them. Most original PS-10's will need to have the woofers refoamed by now too. The typical foam rot issue. The replacement surrounds are widely available. Carry on....

BTW- I did a recap on a pair of PS-10 crossovers. Just for S's&G's I measured the capacitance and ESR values on the original caps. All the original caps measured within tolerance for capacitance and the ESR was well under .5 ohms also. The crossover capacitors may be the last place to do your troubleshooting based on my experience. Just FYI.

NOT work. I put an ohmmeter on the pot and rather than a smooth resistance change when moving the control, the resistance was jumping and as I approached 1/8 turn from minimum resistance on the pot, the pot would go open. Even after a repeated cleaning/treatment with Deoxit. The resistance measurements exactly coincided with what I was hearing. PE has a 15 Watt version of the potentiometer that is a very close match. Unfortunately for me, the tweeter was still dull/distant sounding with a new potentiometer. I finally went to the auction site (as suggested above) and bought a good used one. That fixed my final issue. I concur with GD70 too-- they are quite good sounding speakers for what they are. That small footprint is a big plus for locating them. Most original PS-10's will need to have the woofers refoamed by now too. The typical foam rot issue. The replacement surrounds are widely available. Carry on....

BTW- I did a recap on a pair of PS-10 crossovers. Just for S's&G's I measured the capacitance and ESR values on the original caps. All the original caps measured within tolerance for capacitance and the ESR was well under .5 ohms also. The crossover capacitors may be the last place to do your troubleshooting based on my experience. Just FYI.

Hi, I would like to know if anyone knows how the ps-10 mid-range is wired? in phase or out meaning is yellow on the positive side red do or is the mid range reversed, i unplugged and assumed they followed yellow as positive or same polarity on each driver? I had these for 28 years and recapped them and are replacing tweeter with a high quality Morel and a new mid range. Thanks Phil

 

[GoRNR]

Hi Phil- I traded the speakers and cash for another component about two months ago, otherwise I could check the hookup on the pair I had. I'm sure someone else will get you an answer. You may also want to join the Design Acoustics Group on Yahoo. There are hundreds of photos of DA speakers including many internal photos. There are also some very knowledgeable members there that can probably answer your question on polarity straight up. I think that's saying something- having owned the speakers for 28 years. Congrats! What mids are you using to replace the originals??

 

[philnext]

Hi Phil- I traded the speakers and cash for another component about two months ago, otherwise I could check the hookup on the pair I had. I'm sure someone else will get you an answer. You may also want to join the Design Acoustics Group on Yahoo. There are hundreds of photos of DA speakers including many internal photos. There are also some very knowledgeable members there that can probably answer your question on polarity straight up. I think that's saying something- having owned the speakers for 28 years. Congrats! What mids are you using to replace the originals??

I will check them out but they will say also, that i wouldn't replace the drivers, why not i say, DA, used cheap speakers but i feel the highs are now lacking after 28 years, cause I need to use 2 ESS om11aM heil transformer ribbon transducer for highs now, they are 30 years old now worth 350 dollars each new. I am using a alum cone mid speaker from
HiVi M5N 5" Aluminum / Magnesium Mid-bass part #297-436 from Parts Express. may have to cut some wood. And the tweeter is a
Morel MDT 29 1-1/8" Soft Dome Tweeter part #27-010 I can tweak the crossover if needed upgraded with these fat Mylar caps soldered in parallel to make the values I need, they are huge.

 

[teal'c]

 

[iramegdal]

^^^ +1 stickman probably has it right on. Although the potentiometer DA used for the tweeter level appears pretty robust, I've read on this board and elsewhere the potentiometer is prone to intermittent operation and requires cleaning. From my own experience cleaning did NOT work. I put an ohmmeter on the pot and rather than a smooth resistance change when moving the control, the resistance was jumping and as I approached 1/8 turn from minimum resistance on the pot, the pot would go open. Even after a repeated cleaning/treatment with Deoxit. The resistance measurements exactly coincided with what I was hearing. PE has a 15 Watt version of the potentiometer that is a very close match. Unfortunately for me, the tweeter was still dull/distant sounding with a new potentiometer. I finally went to the auction site (as suggested above) and bought a good used one. That fixed my final issue. I concur with GD70 too-- they are quite good sounding speakers for what they are. That small footprint is a big plus for locating them. Most original PS-10's will need to have the woofers refoamed by now too. The typical foam rot issue. The replacement surrounds are widely available. Carry on....

BTW- I did a recap on a pair of PS-10 crossovers. Just for S's&G's I measured the capacitance and ESR values on the original caps. All the original caps measured within tolerance for capacitance and the ESR was well under .5 ohms also. The crossover capacitors may be the last place to do your troubleshooting based on my experience. Just FYI.

My PS-10As were in excellent condition (near mint) when I got them. Woofer surrounds were rotted and I replaced them in my typically sloppy way. Happily they are not seen. The toggle switches for the tweeter level seem to work well. I had wondered whether I might notice any sound quality difference if I recapped them (something I have never done to any speakers). It sounds as though you do not believe that it would make much difference. Correct?

 

[GoRNR]

In my case that is correct. I did cap replacements in just one speaker to test if I could hear a difference. To my ears there was a barely perceptible audible difference. There seemed to be slightly, and I do mean slightly, better "decay" and "depth" to the sound. If the speakers are your primaries it might be worth replacing all the caps. If they are used for surround or rec room or lesser use, it may not make enough audible difference. The previous use may come into play since the speakers are 30+ years old now, but for the pair I had, the caps measured in capacitance tolerance with moderately low ESR.

 

[philnext]

View attachment 874473

Thanks for post of speaker but I still need to know if all speakers follow the same rules meaning yellow positive on all drivers, and also just to note the old drivers are not that good, i replaced them with high quality tweeter and mid-range and the sound is greater now than ever. I may do woofer next but waiting.
regards Phil

 

[Gingahippy]

Hey Philnext, how close were those tweeters to original specs? I'm having trouble finding a replacement.

I pulled it and tested it, no continuity. Definitely the tweeter.