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Pass amp paired with audio research pre?

 Wondering if anyone has had experience matching a pass labs amp with an audio research preamp. Do they make a good combination?  Thinking  about audio research reference 5SE matched to one of the X series pass amps. I have Harbeth 401.2 speakers...kind regards 
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georgehifi's avatar
georgehifi
10,312 posts
 
So load on the Ref 5 is about 15k ohms. I think you’d have to go below 10k to really start seeing any degradation in response or output.


Like I said above the AR Ref5 will have no problem. It’s 300ohm SE or 600ohm BAL outputs, and into 20k amp that’s no problem at all, and the coupling caps at 10uf and are fine down to -3db at 0.57hz also.

Worst case the AR Ref5 would be fine even seeing an amp load down to 3k SE or 6k Bal and the 10uf cap into the 3k would be still be only -3db at 5hz still ok.

Cheers George
bdp24's avatar
bdp24
9,868 posts
 

@fanotunes, Tim deParavicini's EAR-Yoshino electronics don't get much love here (though they do elsewhere, including at Positive Feedback by Robert Levi, and in the UK press, especially Ken Kessler in HFN&RR. Ken loves Tim's stuff), but his 868 and 912 pre's are designed to drive a 600 ohm load. Paravicini does a lot of work in pro studios (including Pink Floyd's), where 600 ohms is the standard.

Those pre's have no trouble driving a 10k ohm power amp input. They also are fine sounding, the 868L being noticeably better imo than the ARC LS-16 (I've had both). It had better be, costing over twice as much new, and twice as much used! It is a pure-tube design, the LS-16 a ss/tube hybrid (as are all the LS models). By the way, your RM-200 is called by some a hybrid design, because of it's bipolar input stage (the driver and output stages pure tube), which po's Roger Modjeski. But that's a story for a different thread ;-) .

fanotunes's avatar
fanotunes OP
33 posts
 
 Thank you, everyone, for the responses. Sorry for the late reply. I’ve been traveling for the last two days ( 23 hour drive from Spencer, Iowa to Beaufort, North Carolina! )

 Thank you for the discussion regarding input and output impedance. I learned something there! 

monoogan: 

If I understand correctly, you were running an x350 with a ref 5.  No issues with impedance.  What sort of music do you listen to? And how does it sound? What sort of speakers do you have? 

I really hope moving from the LS 16 to the Ref 5 will solve my concerns as i’ve always liked my Music Reference.  If not, a Pass amp may be the next step.

My system seems just a bit too polite. Right now, I am attributing that to the LS 16. If not that, thinking a more powerful  solid-state amp will help.

Could also be the transfiguration proteus as it seems pretty laid back too...?

bdp24's avatar
bdp24
9,868 posts
 
@fanotunes, I would attribute the lifeless sound you hear to the LS-16 before the RM200 (I've owned both, and dumped the 16). Check into how ARC creates the balanced XLR outputs on the LS-16. Since the RM200 has true balanced inputs, you may as well feed it a true balanced signal (though it will accept unbalanced without modification or sonic penalty, says Roger Modjeski). In his EAR 868 (and in the 912), Tim deParavicini creates that pre’s balanced outs by way of transformers (standard in recording studio equipment). Though I don’t know it to be true, it may be that ARC does so with opamps, which is very common in consumer gear.
markcdaniel's avatar
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markcdaniel
45 posts
 
Why not pair a Pass pre with the Pass amp? Both are excellent pieces of equipment and should match well.
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