[amblerjeff]

Is anyone running the NuForce 9.02 with ProAc speakers?  I own a pair of Response 2.5's running off of a Conrad Johnson MF2500 and am intrigued by the NuForce amps.

[Halfdeaf]

The 9.02s will give your ProAcs bass with a woody...

The damping factor control over the woofers tightens up the bass to a point where it almost sounds like they go a half-octave deeper.

In the 70s I had a Phase Linear 400 which at the time had an unheard of DF of 1000.  Over the years I had it I used it with a variety of ported and acoustic suspension designs, most with big honking woofers, and got used to tight base.  The treble was pretty grainy, but what a bottom!

After I got rid of it, I just kinda learned to live with sloppier bass - but in the case of my tube amps I didn't seem to notice so much because of the enriched upper midrange and high end openess.

Before I got my 9.02s, I had read about their DF of 4000 and thought "What difference can a high DF make in my puny 6.5" woofers in the ProAc 2.5s?"

I hesitate to say you will be bowled over by the difference they make...

... but I was!  There is just an unbelievable amount of bass control with these amps.

Now if I could only afford a good sub (and another 9.02)...

[amblerjeff]

Good to hear about the improved bass.  The fast and deep bass is already a big strength of the 2.5's (particularly for a 2-way w/ a 7" driver).

That said, how is the soundstaging and imaging?  Also, how is the frequency balance on the mid and hi's?  IE. is it well balanced or bright, etc.

Are the 9.02's a step up from your previous amps (what were you running before)?  Also, what are you using for your pre and cabling?

It's good to quiz someone with the exact same speakers...  

The 9.02s will give your ProAcs bass with a woody...

The damping factor control over the woofers tightens up the bass to a point where it almost sounds like they go a half-octave deeper.

In the 70s I had a Phase Linear 400 which at the time had an unheard of DF of 1000.  Over the years I had it I used it with a variety of ported and acoustic suspension designs, most with big honking woofers, and got used to tight base.  The treble was pretty grainy, but what a bottom!

After I got rid of it,  ...

[Halfdeaf]

My current system is here: http://www.audiocircle.com/index.php?topic=25428

For the last few years I've been toying with a variety of mostly older-design tube amplifiers, including amps from Music Reference, Audio Research and MFA.  My standby backup amp is a re-re-rebuilt Dynaco ST-70.

In comparison to these amplifiers, I'd characterize my impression of the Ref 9s as follows:

Good resolution in the upper treble with no harmonic artifacts
The upper midrange is somewhat "sucked-out"
Solid, better defined midrange
Good upper bass with no bloat
Amazing lower bass control

I figure my impression of the upper midrange is probably due to the fact that I'm used to the "bloom" of tubes... (and sometimes I miss that bloom)

Truthfully, I bought these amps 'used' to try them out after seeing all the accolades in the audio press and underground musings.  

In my current situation, I had a problem with the EMI from the amps (I'm in a fringe FM area without a shielded antenna connection - and have access to an excellent 'free-form' radio station...) so I put the amps up for sale on AudiogoN, etc.

While they were for sale, Jason and Casey were doing their utmost to help me ameliorate my RFI problem, and the whole time I'm explaining to prospective buyers why I'm selling the amps.  Meanwhile, I'm still listening to them and realizing they're the best (overall) amps I have heard in a long time...

So I got seller's remorse and pulled my ads.

In the end, I consider the Reference 9s to be an amazing value for the price, and an great complement to my ProAc Response 2.5s...  They have plenty of power to push the 2.5s to their edge.

And the customer support and service from Nuforce is the best I have encountered in a long time!

[amblerjeff]

Thanks for the feedback.  Definately peaks my interest to go audition one at a local dealer in the Philly area where I live.

How would you describe the imaging, soundstage, and micro-detail in the sound compared to your old amp?  Does it allow the ProAcs to cast a wide and deep soundstage?

-Jeff

My current system is here: http://www.audiocircle.com/index.php?topic=25428

For the last few years I've been toying with a variety of mostly older-design tube amplifiers, including amps from Music Reference, Audio Research and MFA.  My standby backup amp is a re-re-rebuilt Dynaco ST-70.

In comparison to these amplifiers, I'd characterize my impression of the Ref 9s as follows:

Good resolution in the upper treble with no harmonic artifacts
The upper midrange is somewhat "sucked-out"
Solid, ...

[Halfdeaf]

The amount of detail shown by these amps is just awesome.  When I stated they seemed somewhat sucked-out in the upper midrange, that was more a perceptive change from what I was used to than a complaint about the sound of the Ref 9s.  They are simply more neutral in their presentation of timbre.

I've always felt "imaging" to be more a property of the speakers than the electronics, and the Ref 9s allow the ProAcs to show that in spades.  Using a demo record such as Telarc's Omnidisc, where there is a cut which breaks-down each section of an orchestra individually, then adds them together, you can really get a true feeling of the imaging being presented.  Other good demos are Chesky's Ultimate Demonstration Disc" and OPUS 3's Test Record 1: Depth of Image, which also show off different miking techniques.

Soundstage, I feel, is more room-dependent, and right now I'm trying to find a sweet spot for the speakers in my room to allow the soundstage to "open up".  I'm handicapped by an L-shaped room and a serious lack of WAF in using sound absorption or refraction panels...

Overall, my continued listening to the Reference 9s and the excellent customer support from Jason & Casey have turned me into a serious Nuforce "groupie".  I think the Reference 9s are among the best amps on the market (particularly at their price point).  Their neutrality will absolutely show off your upstream components - which can be a good and a bad thing.  

I'm afraid my purchase of the Ref 9s is going to be one of those "catalytic" audiophile moments in that I'm going to want to rebuild my whole system around them...

Edit:  I should expound a bit on the soundstaging.   The soundstage I referred to above relates to the ability of the speakers to disappear in the listening room, causing the virtual sound image to broadcast behind and beyond the plane of the speakers.  Electronically, the Ref 9s exhibit a superb depth of image in the sound, probably due to the great resolution of these amps.  It is easier to discern differences in microphone techniques between recordings, and in some cases the sound of the room itself is more prevalent (or at least noticeable) than with other amplifiers.