I was planning on buying a BeePre2 kit but some language in the general description gave me pause. It said "The upgrades will also make the BrePre2 a good match to many solid state and push-pull tube amps". I'm curious why it is only a good match to many but not all amps? Initially, I would use it with the PS Audio M700 monoblocks. The manual says they have an input impedance of 50K ohms. Is that a problem?
BeePre2 and Solid State Power Amp?
- Thread starter pinwa
- Start date
Paul Joppa
Moderator
50K is not a problem.
The language is more of an implication that the BeePre 2 is a far better match to solid state amps than BeePre 1. With all the upgrades, it will drive a 5K load easily. The stock preamp will be happy with 30K or more.pinwa said:
What can be a little nebulous and easy to forget about is that many solid state subwoofer plate amps are 10K, so that's the kind of thing you'd want to watch out for!
There are also main power amp designs from various manufacturers with low input impedance - a few examples would be First Watt F1J, Pass Labs Aleph, Bryston 28B SST2, Aragon Iridum. This is possibly due to temporary insanity of the designer, as it is typically one random model out of the manufacturer's product line that has this low input impedance. So it's worth looking up the input impedance of whatever amp you have when looking for a preamp to go with it.
I had to match up a Foreplay III with a Pass Labs Aleph many years ago at CES and there were several phone calls to PJ to work out the necessary changes along with a few runs to Radio Shack and a lot of field expedient soldering in the exhibit room to accommodate the abnormally low input impedance of the Aleph. Luckily those were the days when I hauled a rolling tool case with me to shows. Nothing like a little pressure to make a trade show fun. If still did shows now I would haul PB with me instead.
