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Old 14th May 2011, 12:08 PM   #4091
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It's an almost impossible task to read 409 pages here to find something.

Can someone tell me on what pages I may find the ccs controlled version for LDR attenuators?
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Old 14th May 2011, 10:07 PM   #4092
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Look search for maximus (Paul Hynes) posts I think he's doing one.

Cheers George
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Old 15th May 2011, 04:30 AM   #4093
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Hi bp,

There is a version that does drive low impedance loads built by "Blues" [WarpSpeed"] - It's quite happy driving my F3 with it's input impedance of 9kR and I understand it is okay down to about 3kR - the "normal" versions (George's & Uriah's) do require a buffer, and/or gain stage.
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Old 15th May 2011, 01:45 PM   #4094
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My concern is that my power amp's impedance, as many out there, is around 20K. Wouldn't I need a buffer?

About the input impedance, am I missing something is is it fine to feed low impedance sources into it?
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Old 15th May 2011, 05:54 PM   #4095
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Originally Posted by carlmart View Post
. . . my power amp's impedance, as many out there, is around 20K. Wouldn't I need a buffer?
I drive a Quad303 (input impedance = 20K) with a Lightspeed with no apparent issues. My advice would be just to try it.

HTH

Dave
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Old 15th May 2011, 07:48 PM   #4096
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Originally Posted by Ryelands View Post
I drive a Quad303 (input impedance = 20K) with a Lightspeed with no apparent issues. My advice would be just to try it.
With no buffer?

OK. Good advice. I was going to do that anyway, but I saw Nelson Pass LDR + preamp, and it needed several things I can't find here, like more matched LDRs and matched SJ170/SJ74.

If I was going to provide a buffer, then I would have to get the parts.
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Old 15th May 2011, 08:32 PM   #4097
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With no buffer?
With no buffer.

Of course, I've no idea how it would sound if I had a buffer - but I don't. And it sounds pretty good to me.
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Old 16th May 2011, 08:29 PM   #4098
udailey is offline udailey  United States
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Nowadays I drive a 10k amp with mine. Just took it to a show and did not have a problem. Got many great comments and am working with a dealer who says its the best pre he has ever heard. I have used a buffer though and have posted my impressions in this thread in the last year or so.
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Old 16th May 2011, 08:36 PM   #4099
ua100k is offline ua100k  United States
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Quote:
Originally Posted by carlmart View Post
My concern is that my power amp's impedance, as many out there, is around 20K. Wouldn't I need a buffer?

About the input impedance, am I missing something is is it fine to feed low impedance sources into it?
I use the Warpspeed without a buffer on multiple set ups with no problems. However I cannot say what the impedances were for all of them. I did use it tube and solid state without buffers.

It is cheap enough to try a few of them if you can. Warpspeed and DIY Paradise Eva II comes as a completed unit if you prefer not to get your hands dirty. Myth, The Truth are a little more costly as finished units.
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Old 16th May 2011, 08:39 PM   #4100
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Originally Posted by ua100k View Post
I use the Warpspeed without a buffer on multiple set ups with no problems. However I cannot say what the impedances were for all of them. I did use it tube and solid state without buffers.

It is cheap enough to try a few of them if you can. Warpspeed and DIY Paradise Eva II comes as a completed unit if you prefer not to get your hands dirty. Myth, The Truth are a little more costly as finished units.
The only thing important is the output impedance of the source, in this matter. Keep it under a couple hundred ohms as George pointed out (years ago?) and you'll be fine.
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