Any benefit from" same brand" amp/pre-amp??

Using the same brand should negate any issues with output/input sensitivity and impedance matching. Why would the Class D have limited bass?

synergy

The Stratos will work with the quad preamp. Output/input sensitivity is fine. What speakers will you be using?

Bass is limited by transformer and any of the indirect coupling of the output stages. It's less-likely limited by class of operation.

'd' amps may be said to have problems with hi frequencies, especially with low impedance loads...at those frequencies. The output zobel is the cause.

Look up the info on the top B&O ASP 1000 module as used by Bel Canto and many others.

http://www.icepower.bang-olufsen.com/files/solutions/icepower1000asp.pdf

It's pretty much all done at 30khz, into 4 ohms.

LF problems? Tell that to literally dozens of Sub Makers!

To UNSOUND: I am not sure why the TAS reviewer made that claim: (see TAS issue 203--July August 2010); I am not as techically hip to challenge the claim and also may have misinterpreted his statement..... However, there is an internet audio dealer who offers 2 separate levels of upgrade to the Quad 909 amp which is said to improve the bass; but the upgraded versions are not inexpensive---there is approx a $300 upcharge to go to level 2; I think Quad would probably invalidate the warranty of "new" pieces that were modified. For the record, I have a pair of Acoustic Zen Adagios. Thanks Jim

Sunnjim, perhaps it's something peculiar to that Quad amp. Most seem to feel that with the right speakers, that bass response is a strong suit of some Class D amps.

Magfan, I very well could be missing something here, but why would one care much about what goes on at 30Khz?

Magfan made his point clear. Who cares even above 16kHz?
I use for 7 years Sunfire SRA class T amp which is an advance from class D technology with addition of sigma-delta signal encoding/decoding and found it superior to famous Wyred4Sound models.

Perhaps that one went over my head, but I'm not sure Magfan was being sarcastic.

If you don't have the ability to try many combo's at home , a same brand match will work , most times .

I am an advocate of having the same brand of components...they were matched for each other, and there is no danger of anything untoward. I have and all Ayre system which brings out the best of each individual component.

I always try to keep within the same brand of preamps and amps to take away the guess work. I don't know how to interpret specs of amps and preamps to see if they will work well together. And even then it may be more of a crapshoot if an un-matched amp and preamp will have good synergy.

In my main system now I have a Kavent S-33 preamp and a Kavent P-3300 amp and they really were meant to be together. Everything sounds good to me. I also found that the P-3300 I found has a 35db gain and the S-33 preamp has a provision on the remote to reduce the gain by -10 dBs. If you had another preamp there won't be a way around it if the gain was an issue for you.