Amp Design Advice

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My system is bi-amped and I am building monoblocks to power the woofers. Each monoblock will power two 8 ohm 8" drivers which are 85db efficient. As the drivers are wired in parallel, the drivers are 91db efficient @ 4 ohms.
Each monoblock consists of two Borbely Servo-50s which are bridged to one channel. Currently, both chanels of the monoblock share a 900VA transformer and power supply. Each channel has 75k microfarad of capacitance and 5 pairs of output devices. Each monoblock is rated at 200w, has 150k microfarads of capacitance and 20 output devices.
Because the monoblocks will ONLY be used for bass response, the amps were re-biased to used BJTs instead of MOSFETs. The output driver is still a MOSFET.
Questions:
1) Does it matter that the output driver is still a MOSFET for my application?
2) Would adding a second 900VA toroid and power supply provide significant, i.e., audible improvement in bass response (Each monoblock would become dual mono with two 900VA transformers).
3) I could increase the number of output devices for each monoblock from 20 to 32 and use a MOSFET output driver which could handle more current. Again, would this audibly improve bass response?
In answering, please keep in mind that these monoblocks are SOLELY used for bass response and will not be run full range. Also keep in mind that I am not changing the rail voltages so the power will remain the same.

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Topic - Amp Design Advice - ccd 18:32:57 05/06/00 (4)

Re: Amp Design Advice - Hans 10:21:24 05/07/00 (0)

Re: Amp Design Advice - Sean 23:54:51 05/06/00 (0)

Re: Amp Design Advice - Trevor Wilson 20:48:50 05/06/00 (0)

Into the realm of opinion.... - BrianG 20:13:24 05/06/00 (0)

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