Can I bridge my SDA-1C speakers?
Comments
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sort figured it was a moot point but had to ask. I honestly wouldn't have a valid use for one other that to say I had one. I've caught a glimpse of the innards and it way over my head. At any rate. sounds like heiney got the op straightened out a bit. Or as Dad used to say UTRFTS or UTTAIS. lolToo much **** to list....
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My receiver is set to 4ohm mode which is just a current limiter and I have the volume capped at -5dB. If I bridge them, I will still leave it in current limited mode.
You are starving your speakers. Current is what they love, so put your AVR back to 8 ohms and just forget all about bridging.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Can't someone that has a copy just scan the pages and upload it?
No, it is a copyrighted publication.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
What you would have been measuring is the DC resitance of the woofer(s) and any inductors (and wiring) in series with them. The DCR is usually an ohm or more less than the stated nominal impedance which adds the effects of reactive components(capacitance and inductance) to the resistance.When I first purchased mine they were 6.1 nominal. Actually I was a bit surprised a moment ago to read 4.0. Is this any point of concern? -
Assuming that I can't get the AI-1 cable, are there instructions anywhere to make my own adapter?
Looking at this picture:
Can anybody link me to a suitable transformer, and also regarding those eight wires coming off the transformer, where do those get connected? I don't have much knowledge about this sort of thing. How large a transformer do I really need to make it work? -
Brand new, never used AI-1 interface unit available. PM for info.
The AI-1 has "left the building", thanks 003! If the sales rating system ever gets fixed I'll write you a +
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Ummmm...yes. I gave you the link in an earlier post.Assuming that I can't get the AI-1 cable, are there instructions anywhere to make my own adapter?If he builds an AI-1 to the same specs as the OEM Polk unit, it would be about fifty bucks, maybe less. The raw transformer would be something like $20--$25 shipped, plus some cables and terminations.
http://www.polkaudio.com/forums/showthread.php?t=55888 Post #6.
Additional info:
The OEM Polk unit is good for .13 amps; and that is NOT enough...but it was good enough for Polk at that time. Any suitable isolation transformer than can handle more than .13 amps is almost certainly better than the OEM unit. Using the "Dreadnaught" style, at something like 6 or 7 amps is quite superior...but not absolutely required.
I'd say an isolation transformer of the OEM size as a MINIMUM; but better would be to go with the Dreadnaught-style pioneered by Darqueknight.Looking at this picture:
Can anybody link me to a suitable transformer, and also regarding those eight wires coming off the transformer, where do those get connected? I don't have much knowledge about this sort of thing. How large a transformer do I really need to make it work?
http://www.polkaudio.com/forums/showthread.php?t=74472
Lots of reading there.
PS: If you're using current-limiting, you're very likely making a mess of the sound quality. -
I have acquired a BRAND NEW AI-1 cable, and it's terminations are both pin/blade. I hope it works! If not they do seem to have a decent demand.
Anyway, I don't know the technical operations behind audio, so exactly what benefit does a transformer rated for higher amps provide? Surely the polk implementation must work, or they wouldn't have offered it. Will it somehow not sound as good as a larger transformer, or I won't be able to turn it up as loud? -
F1nut wrote:You are starving your speakers. Current is what they love, so put your AVR back to 8 ohms and just forget all about bridging.PS: If you're using current-limiting, you're very likely making a mess of the sound quality.
He's doesn't seem to be getting that point.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
The electrical signal that "powers" the SDA system is dependent on two things: the volume level you're listening to, and the difference in signal between the left channel and the right channel. In other words, the music (or speech...or noise) you're listening to, and the volume level you've chosen for playback.what benefit does a transformer rated for higher amps provide?
The most difficult possible load for that transformer, I suppose, is to have one channel of LOUD music, while at that instant there's silence in the other channel. There'd be maximum difference between the channels, and a lot of voltage driving a lot of current.
The Polk AI-1 transformer has a capacity of .13 amps. But that's WAY less than the plain ol' interconnect is capable of transmitting. If you look at the Dreadnaught link posted above, Matthew Polk Hisself has proclaimed that "ideally" the transformer should be capable of transmitting 5+ amps.
You now understand the situation. The transformer "should" have a 5+ amp capacity, but due to the enormous expense and shipping weight, the AI-1 in production form was reduced to a shadow of what it should have been.
You're right. It "works". But the tiny transformer will saturate at a low volume level; and of course the whole shebang was compromised in terms of parts quality. You will be able to use it with your bridged receiver; nobody is making any guarantees that the result will have the sound quality you're hoping for.Surely the polk implementation must work, or they wouldn't have offered it. Will it somehow not sound as good as a larger transformer, or I won't be able to turn it up as loud?
As for whether "your" 1Cs are AI-1 compatible, I'd be looking to see that there's essentially zero ohms between the blade socket (not the pin socket) and the negative terminal of the speaker. If you've got a very-low-resistance connection there, your speakers should be AI-1 compatible. If the blade socket has more than about one ohm resistance to the negative terminal, bets are off. It really ought to be a dead short. -
No, I didn't miss that point, I will turn off the current limiter :biggrin: I only had it on because I heard that these speakers can be hard on amps, but I will still leave the volume capped at -5dB and I do have a 5 year warranty, so we'll see how it works out.He's doesn't seem to be getting that point.As for whether "your" 1Cs are AI-1 compatible, I'd be looking to see that there's essentially zero ohms between the blade socket (not the pin socket) and the negative terminal of the speaker. If you've got a very-low-resistance connection there, your speakers should be AI-1 compatible. If the blade socket has more than about one ohm resistance to the negative terminal, bets are off. It really ought to be a dead short.
Thank you! I measured with my DMM and the negative terminal and blade socket measures ZERO ohms for me! To make sure it wasn't broken I also tested with the pin socket and it instantly showed up as 14 ohms, so hopefully I am good to go! I am aware the AI-1 may not be the greatest, but I will test it for myself. I'd rather not have another box that I don't have room for. I need to work with what I've got ... which unfortunately isn't the greatest, but could be worse.... hopefully. My receiver was the best Onkyo made at the time I got it and is actually specifically advertised as high current.
I look forward to it, thanks!The AI-1 has "left the building", thanks 003! If the sales rating system ever gets fixed I'll write you a +
EDIT:
By the way... quick question about speaker placement. All guides I see for home theater setup say that the front speakers should be angled in slightly at around 30 degrees, facing the focal point of the home theater. Is that true for the SDA-1s, or is that not good due to the SDA effect? -
If you're getting cold feet about the AI-1 purchase just let me know. I don't want you to regret buying it.
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If you're getting cold feet about the AI-1 purchase just let me know. I don't want you to regret buying it.
No, now that I know it should work, and will require no assembly on my part, and should fit in the small space I have available, I think I'll be OK. Thanks! :biggrin: -
reported.
Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
"I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion."![:\](https://forum.polkaudio.com/resources/emoji/confused.png ":\")
My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....
"Green leaves reveal the heart spoken Khatru"- Jon Anderson
"Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee -
By the way... quick question about speaker placement. All guides I see for home theater setup say that the front speakers should be angled in slightly at around 30 degrees, facing the focal point of the home theater. Is that true for the SDA-1s, or is that not good due to the SDA effect?
Never toe in SDA speakers.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
I have acquired a BRAND NEW AI-1 cable, and it's terminations are both pin/blade. I hope it works! If not they do seem to have a decent demand.
So who verified that your 1C's can even use the AI-1? I must have missed that post. Good luck.
H9"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul! -
By the way... quick question about speaker placement. All guides I see for home theater setup say that the front speakers should be angled in slightly at around 30 degrees, facing the focal point of the home theater. Is that true for the SDA-1s, or is that not good due to the SDA effect?
There are very specific instructions for setting SDA's up properly. The closer you follow the guidelines the better they will sound. As F1 stated no toe in at all.
H9"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul! -
So who verified that your 1C's can even use the AI-1? I must have missed that post. Good luck.
H9
Two modes of verification
First, it was suggested I measure the impedance from the blade socket to the negative speaker terminal, and if it was zero, it should work. It was in fact zero.
Second, I found a picture of the list that says what SDA-1Cs work with it here:
http://www.polkaudio.com/forums/showthread.php?t=70236
I am in the clear by a long shot
Thanks, I'll be sure not to do that!Never toe in SDA speakers. -
Well, you're set then!
Just an FYI, almost all the information contained in Darqueknight's SDA Compendium is on Club Polk somewhere. That's one of the main reasons he decided not to do another edition. Granted, having the info in one easy to use binded book is much more convenient obviously, but there aren't any "secrets" in the Compendium that aren't here somewhere in the archives.
H9"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
