None of us asked the OP what s wrong with the speaker as it is from factory, why he thinks the polycel tw is limiting, or what kind of cartridge fits the turntable (as for guess the amount of HF that the system is able to output), maybe is all matter of tweak the tweeter level
(L-pad or wathever it is)
(L-pad or wathever it is)
Egg crate is very different from "egg-crate" foam. Don't use egg crate. Use acoustic foam, no matter how it looks.
Here is a link to the Sonic Barrier products:
https://www.parts-express.com/brand/sonic-barrier/494
And I still wouldn't use egg crate foam. I think it's kind of useless.
https://www.parts-express.com/brand/sonic-barrier/494
And I still wouldn't use egg crate foam. I think it's kind of useless.
Egg crate foam is similar to flat foam, if we calculate average thickness and compare it to flat foam thickness.
I've heard SM60's, SM80's and SM120 or SM150's. At that time, the Polycell tweeters had a tendency to shriek. Not sure about the later models. It would be interesting to see a measurement of one.
The existing XO is a second order, most likely 3000Hz. I would like to drop in these tweeters: http://www.parts-express.com/pedocs...ilk-dome-truncated-tweeter-specifications.pdf
With a silkie, I could easily change to a 0.47 polypropylene cap without worrying about shrill or harsh. The woofer specs are unknown. Given a mass market Infinity 6.5" speaker from 30 years ago, would the Dayton be close to a drop in fit? After routing to fit. Thanks
With a silkie, I could easily change to a 0.47 polypropylene cap without worrying about shrill or harsh. The woofer specs are unknown. Given a mass market Infinity 6.5" speaker from 30 years ago, would the Dayton be close to a drop in fit? After routing to fit. Thanks
Are you sure you wouldn't rather just make a new pair? It's considerably harder for you to match a new driver to an old speaker than it is to just build a known kit.
Madisound, Parts Express and Meniscus have plenty of kits for you. 🙂
Best,
Erik
Madisound, Parts Express and Meniscus have plenty of kits for you. 🙂
Best,
Erik
That's exactly what i'm trying to say from post #2 ...
For a tweeter drop in replacement you should ask yourself:
is the impedance profile the same?
is the FR the same?
do I need to pad it down?
The chance of having the answers yes, yes, no is around 0. Without measuring equipment and bunch of crossover elements it is very hard to obtain a good outcome.
Ralf
For a tweeter drop in replacement you should ask yourself:
is the impedance profile the same?
is the FR the same?
do I need to pad it down?
The chance of having the answers yes, yes, no is around 0. Without measuring equipment and bunch of crossover elements it is very hard to obtain a good outcome.
Ralf
I've read that article but didn't find anyting supporting that an audio grade aluminium electrolytic of few uF will produce audibly more distortion than a film cap. OTOH, using a film cap instead of an electrolytic will change the crossover behavior because of the very different ESR. That will be audible because of the change of SPL of the whole tweeter frequency range. Hence my suggestion to replace film with film and electrolytic with electrolityc. If you want to replace an electrolytic with a film cap you have to measure ESR and add an appropriate resistor. As I said the real problem with electrolytic caps it that they change capacitance over time, and this is the reason why an aged electrolytic cap should be changed.
Ralf
The infinity speaker is rated at 94 dB sensitive There may be a little specsmanship (cheating), but a typical 90dB tweeter is not likely going to drop in. I know there are some 96 dB tweeters here you could try. Might need a series resistor.
As far as the aluminum cap having high ESR, a brand new one won't, and neither will a good film cap. Put a film cap in there and be done with it. Even mylar is better than electrolytic, but the price difference between mylar and poly at this component value is very small.
I last listened to an SM series >25 years ago. The excess highs could have been from cone breakup on the woofer. I can't find any measurements of a polycell online. There is one from a guy using an RS SPL meter and graphing with excel, but I wouldn't trust it. They may be fine, or maybe were crossed too low and distorting in the SM80 that I distinctly remember being sibilant and fatiguing.
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From my experimentations dropping random drivers into existing designs never produced any good results.
I was listening to the stock speakers today, on the local jazz station, and I could barely hear the cymbals. I turned up the treble, with a slight increase in the highs. So I will definitely be getting some new caps from PE. And does anyone use the 0.1μf or 0.01uf parallel bypass cap, or was that just a passing fad a few years ago?
Thanks,
Joseph
Thanks,
Joseph
Oh, come on!! You are fooling yourself! The difference in ESR between the caps is likely less than 0.3 ohms, and that will make NO audible difference in the crossover point or SPL.
It's not the resistance, but the Dv/Dt that you have to look at.
It happens that it's better when the cap has an high voltage, so welcome to film caps.
It happens that it's better when the cap has an high voltage, so welcome to film caps.
My other question about bypass caps. Does anyone use the 0.01uf parallel bypass cap, or was that just a passing fad a few years ago?
Thanks,
Joseph
Thanks,
Joseph
If that's the case. I'd say bad tweeters or XO's. Cause those Polycell tweeters tend to have a very shrill bark to them. At least to my ears. I love vintage Infinity speakers. But the SM series was very disappointing compared to their other offerings.
I switched to the Dayton metallized polypropylene capacitors, 4.7 microfarad. More highs, not shrill, relegated to the basement work space.
For my daughter's AR-XA turntable, I found a pair of Baby Advent cabinets in the basement, and made them into a pair of Karma Indignias.
Thanks,
Joseph
For my daughter's AR-XA turntable, I found a pair of Baby Advent cabinets in the basement, and made them into a pair of Karma Indignias.
Thanks,
Joseph
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