Search found 263 matches

by ricardo
Sun Jul 10, 2016 10:36 pm
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

At one time it was one of the 3 best small speakers in the world. I'll be in the market for small speakers for my cabin. If your's are still made I'd like to check them out. .... Any suggestions for a little speaker that is priced for mortals? I think I'm going to get this to power them. http://www...
by ricardo
Sun Jul 10, 2016 7:21 am
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

You mention that a test person should rank 3 music fragment of which 2 are the same. Later in your posting I read that the test person should tell his preference. So therefore my question: what criterium was than used for ranking ? This is entirely up to the listener. In earlier attempts at formal ...
by ricardo
Sat Jul 09, 2016 12:34 am
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

The tested very low noise preamp might be just a better design with a higher overload margin and maybe even a balanced design with a high CMRR compared to the other one in the test. Apart from two ZTX bipolars, being steadily improved with modern production techniques, all active components in Wayn...
by ricardo
Fri Jul 08, 2016 1:38 am
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

This is not meant to criticize the nice circuit design in this thread, having only 0.33nV/rtHz or 12.5dB less noise. It is only to make aware that in case of using Fet's instead of bipolars, generating slightly more noise, does not at all render the circuit into a less valuable design. There is sti...
by ricardo
Tue Jul 05, 2016 10:14 am
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

No problem, to which one are you referring: the graph with the 3 different noise measurements, the measurement of the CMRR or the "measurement" of the signal with/without A/D/A. The circuit for which you posted 10Hz_2Khz_1.jpg A recording magazine assembled a panel of recording studio pro...
by ricardo
Mon Jul 04, 2016 6:03 pm
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

I would say, measure where possible to find all possible design flaws first, but at the end listening to music can only be the final test. Nonsense! The most important thing is the Price Tag . Secondly, you have to deface any 5532/4s so they can't be identified and print "hand carved from soli...
by ricardo
Sun Jul 03, 2016 6:05 am
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

Signals can be heard below the LSB in modern digital conversions also (I won't veer off into a discussion of dither, oversampling, etc). Less is always better but how much better could be subjective. If it can't be heard, it is a TERRIBLE digital signal chain. I expect to hear a clean 1kHz sine at ...
by ricardo
Sun Jul 03, 2016 5:31 am
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

10Hz_2Khz_1.jpg ... Since I cannot retrieve the exact filter bandwidth and gain setting, you must see the vertical axis as a relative dB scale. Can you post the circuit which gave this results? Presumably, it has all the good stuff you feel important including nA current throught the cartridge. It'...
by ricardo
Thu Jun 30, 2016 7:04 am
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

1) A Cart coil is made from a very tiny wire, that like all wires can only have a max current. That is said to be the reason why (some) manufacturers mention that you should never measure the internal resistance with a multimeter. Wanna tell us which makers are these? If they are MC makers, this st...
by ricardo
Tue Jun 28, 2016 8:14 pm
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 499
Views: 772012

Re: A Low Noise Balanced In Moving Coil Preamp Using the ZTX

All effort has been successfully invested in getting a very low noise input noise, but what about DC current flowing into the cart. With 5 to 10mA collector current per ZTX851, Ibias and for that reason Ios must be in the many multi micro amps. Isn´t that much too high and therefore over the top fo...