I recently had some Proac EBS with no tweeter output. The Solen caps in line with the tweeter had failed - very unusual for a polypropylene cap.
Proac problem: tweeters or crossover?
Recently, something moved me to listen closely to the tweeters, and when I couldn't hear anything I hooked up the speaker cable just to the tweeter binding posts. I can't say there was no sound at all, because there was the faintest of recessed, tinkly sound that didn't seem to vary much with the level of the volume control.
I called up Modern Audio and they told me just to get the Scanspeak D2010s from Madisound. I soldered them in this morning. Now the new tweeters are a bit louder than before, but not nearly as loud and not as strong on the higher frequencies as I would have expected. They still sound subdued, recessed and tinkly/jangly, but not as much as before, and there's a bit more change in level when varying the volume control. This is as always with the cable hooked up only to the tweeter binding posts.
So...is this how they're meant to sound, or is there a problem with some component in the crossovers? If there is, it must be the same in both speakers' crossovers. I wish the result of the change-over had been less ambiguous: either virtually no sound, or a great improvement. Instead, it falls somewhere in between, but the result makes me think that I haven't solved the problem.
BTW, the Response 2.5s must be ~17 years old. Custom yew finish bought new from Accutronics in Ann Arbor in 1998/99. The mid-woofers still sound great.
Does anyone know what a Proac tweeter driven in the way I've described should sound like when it's functioning correctly?
I called up Modern Audio and they told me just to get the Scanspeak D2010s from Madisound. I soldered them in this morning. Now the new tweeters are a bit louder than before, but not nearly as loud and not as strong on the higher frequencies as I would have expected. They still sound subdued, recessed and tinkly/jangly, but not as much as before, and there's a bit more change in level when varying the volume control. This is as always with the cable hooked up only to the tweeter binding posts.
So...is this how they're meant to sound, or is there a problem with some component in the crossovers? If there is, it must be the same in both speakers' crossovers. I wish the result of the change-over had been less ambiguous: either virtually no sound, or a great improvement. Instead, it falls somewhere in between, but the result makes me think that I haven't solved the problem.
BTW, the Response 2.5s must be ~17 years old. Custom yew finish bought new from Accutronics in Ann Arbor in 1998/99. The mid-woofers still sound great.
Does anyone know what a Proac tweeter driven in the way I've described should sound like when it's functioning correctly?
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- 23 posts total
"03-06-15: Bojack Zd542, "Break in" for tweeters Really? I am sorry, but please don't provide such advice when clearly you know nothing about how electronics or transducers work." Sorry about that. Can you tell me what line of speakers you design? You didn't say. Twoleftears, I forgot to ask in my other post if the new tweeters are exactly the same as the ones you took out? |
Twoleftears, as you may be aware tube amplifiers having output transformers should not be operated without a speaker or equivalent load being connected, especially when signals are being put through them. Assuming you are still using the Cary SET amp listed in your system description, it occurs to me that when you connected the amp to just the high frequency section of the speakers you were running the amp unloaded across those parts of the spectrum where the great majority of the energy of most music is concentrated. I say this given that the crossover point of your speakers is a bit higher than 3 kHz, as shown in Stereophile's measurements, and the rolloff of the high pass part of the crossover below that point appears to be a fairly rapid 18 db/octave. Which leads me to suggest two things: 1)Don't do it no more :-) 2)I'm not certain of this, but it seems to me to be possible that the anomalous sonics you heard when only the high pass sections of the speakers were connected might have been the result of amplifier misbehavior resulting from the improper loading. So I'm not sure that any of those observations were meaningful. And perhaps the differences you observed with the new tweeters vs. the original ones were simply due to what would under normal circumstances be inconsequential differences in their parameters. What I would suggest is that with a little Googling you should be able to find a test record or CD you can order which has a set of 1/3 or 1/2 octave warble tones, or something similar, the set of tones covering the entire audible spectrum. That would allow you to very readily tell whether the tweeters and their associated crossover elements are working properly or not, which I don't think any of us can say at this point with any certainty. Good luck. Regards, -- Al |
Almarg: will do re. test CD. I should have added earlier that I've inserted an Ayre AX-7e into the system (that led to initial scrutiny of the speakers). Zd542, as per original post, Modern Audio, the distributors for Proac in the US, told me to acquire the Scanspeak D2010s. When I queried them as to whether they were identical, or whether Proac did some mods to them or not, they claimed that they were identical. For a while there, there was quite a lot of "cloning" of the 2.5 in DIY designs, so there's a good deal of discussion of components on the web. The SR Signature 2/3s are like this: at the amplifier end, there is a spade, immediately after which the cable splits into two, so there are two separate runs, physically, all the way to the speaker. I don't know what's going on inside, but the run for the woofer is thicker, which is the only way you can tell the two of them apart. Dover: according to the web, the 2.5s use Ansar Supersound caps. I'm keeping my fingers crossed that there's nothing broke. |
- 23 posts total