lcr RIAA transformers

[pjpoes]

DIY HIFI Supply sells these LCR RIAA transformers, with the most accurate curve seen, as they claim. I'm curious if anyone knows anything about this method and how its implimented? Can it be implimented in a typical solid state design? It's quite expensive, but I'm just cirious if anyone knows anything about this method. Thanks.

[phn]

Search the forum or Google. Lots of info out there.

I don't know about "typical." But it can be implemented with SS, and a lot easier than with tubes.

[MRupp]

I way toying with the idea of an LCR based phono stage, especially after I read about Thorsten's implementation. But the Stevens & Billington LCR filter costs more than 400 $, and I think it is not so easy to drive it's 600 Ohms with low distortion and noise, even in a SS design.

By the way, since you asked about whether to use (cheap laid in type) polystyrene or polypropylene caps for your phono stage in your other thread: For the money you would spend on this LCR filter, you can easily buy better RIAA filter caps, such as matched pairs of Reliable Cap TFT teflons, along with, say, vishay resistors, and you might still have money some left.

[pjpoes]

thanks, I really wasn't planning on using it. I was just curious. I wont be using matched teflon caps, but I was planning on using better caps. I wasn't asking about using them, I was asking if they were any good. I have a bunch in some equipment, and wanted to know if I should replace them.

[Steve Eddy]

Originally posted by MRupp
But the Stevens & Billington LCR filter costs more than 400 $...

Is S&B still making them? I noticed recently that they are not on their website any longer.

se

[analog_sa]

Originally posted by pjpoes
DIY HIFI Supply sells these LCR RIAA transformers, with the most accurate curve seen, as they claim. I'm curious if anyone knows anything about this method and how its implimented? Can it be implimented in a typical solid state design? It's quite expensive, but I'm just cirious if anyone knows anything about this method. Thanks.

I don't think riaa accuracy is the main objective of LCR filters. And of course they can be used in SS circuits as long as the equalisation is passive. A friend of mine uses the old Tango module and greatly enjoys the sound. These days Silk manufacture a similar design. Sadly, i have no first hand experience.

[MRupp]

I noticed recently that they are not on their website any longer.

I saw this as well, maybe they still manufacture them on order?

I wont be using matched teflon caps, but I was planning on using better caps

The next best thing would possibly be matched Multicap RTX polystyrene caps. As analog_sa pointed out, the absolute accuracy is not the main objective and normal RC filters should be accurate as well. But you should still match the filter components between channels.

And of course they can be used in SS circuits as long as the equalisation is passive.

Hmmm, I was wondering if the MC stage of the John Curl Vendetta would be able to drive the 600 Ohms That would make it feasible to convert the design into an LCR version. Btw., you can off course use LR filters in an active design. Michael P. Danbury presented such an RL RIAA filter in a phono stage in Audio Amateur 3/1996.