Matching Preamps with amps

[radio-ology]

Hello, are there any specifics to matching a Preamp to an Amp? Or can any be paired together.
I have an opportunity to pick up a Krell kav-250a amp on a deal but there is no pre amp.
I have a Fisher 400cx tube preamp. Can i pair this with the SS krell 250a amp with good results.

I have a Fisher SA 300B amp but its only 30wpc. Im thinking the hi powered Krell would drive power hungry speakers better (like the Reclilinears I picked up)
Opinions are much appreciated
Thanks

 

[gizzyman47]

Yes you can mix and match different makes of amps and pre-amps. How they will perform together can be hit or miss. Right now I'm using a Audio Research "tube" pre with a Yamaha amp. sounds great! I prefer a tube pre feeding a solid state amp. Best of both worlds IMO.
Try the Fisher with the Krell. May be a great combo!

 

[kappclark]

Congrats on the Krell ... specs say input impedance is 100K ohms, so I can't imagine an issue with the Fisher driving it ... not sure of the specs on the 400cx for output impedance, but I bet it will sound fabulous..

 

[larryderouin]

400-CX with 12at7's
L&R Outputs 40Ω
Center output 9kΩ
Recording outputs 12kΩ

400-CX with 7247's
L&R Outputs 30Ω
Center Output 3.5KΩ
Recording Outputs 5kΩ
Remote output 1.3KΩ

 

[Patrick_W]

400-CX with 7247's
L&R Outputs 30Ω
Center Output 3.5KΩ
Recording Outputs 5kΩ
Remote output 1.3KΩ

Not to question your knowledge on Fisher items Larry, as you probably have forgotten more about Fisher products just today than I will ever know in my lifetime, but did you possibly mean 30,0000 or 30k Ω for the output?

I too am thinking about pairing a Fisher tube pre (President of the CX2 variety) with other non-Fisher power amps, specifically MC30s or Acrosound ULIIs. I have seen a post somewhere in AK (search function, how we miss you) mention that the Fisher / MC 30 combo is rather sublime.

Thanks!

Patrick

 

[radio-ology]

Thank you guys for the quick reply.
Im to meet the seller of the krell tomorrow and was concerned that the output of tube amps can be higher than SS and not be a good match. I know you want the load resistance to be higher. So 30 ohms into a 100k should not be a problem. I now feel more comfortable with the deal.
thanks guys!
(and thanks Larry for showing me how to create a post)

 

[larryderouin]

DIRECTLY from the Back page of the manuals. Both are listed on FISHERCONSOLES.COM

With 7247's

With 12AT7's

 

[Patrick_W]

Many thanks!

I was caught up reading about impedances in the Mac forum. Since my MC30s have an imput impedance of 500k ohms I wanted to make sure that they would work. Sorry for the thread hijack. Carry on.