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Who is using passive preamps and why?

Seldom has there been any discussions on passive preamps in the forums and although my experience with them has been limited I have found them so far to be very enjoyable and refreshingly different. They seem to fall into their own category, somewhere between solid state and tube. Finding a preamp that is satisfing has been difficult. Some active solid state preamps can be very good but they seem to inject grain to some degree in the upper registers and some tube preamps are not too far behind. So far I think they should at least be matched up with an amp that has sufficient gain which is often overlooked. Which passives are you using and with what amp? Why do you like them?
phd
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almarg
9,670 posts
 
I don't think anyone has mentioned cable length and cable capacitance yet in this thread. Those certainly being factors that need to be kept to a minimum on the output side of a passive preamp. High output impedance into high cable capacitance (which is proportional to length, as well as varying widely among different cables) will result in upper treble rolloff, and long cables will increase the likelihood of other adverse cable effects as well.

Regards,
-- Al
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almarg
9,670 posts
 
Grant -- I'm not particularly familiar with the VRE-1, but I recall that it includes a jfet (active) buffer stage. Assuming that is in the signal path and is followed by a coupling transformer at the output, I'd expect the resulting output impedance to be much lower than in the case of a purely passive preamp. Perhaps that is why the long cable is not a problem for you?

Best regards,
-- Al
pubul57
3,712 posts
 
Tvad, your VRE-1 isn't really a passive, is it? It simply has no gain, which isn't really the same thing - it certainly has buffering which, if needed, will overcome some problems presented to pure passives in the wrong system context, no?
clio09
3,353 posts
 
The VRE-1 is not a true passive, it is a hybrid design with a JFET buffer stage that eliminates impedance matching issues. Great concept along the lines of the Pass B1 (JFET buffer) and the Bent Tap-X (user selectable buffer outputs).
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