[James Romeyn]

OP proposed amp upgrade, no other upgrade.

Stereo Hypex NC400 would kill any Outlaw amp real or imaginary, and leave no trace of remains.  Have you directly compared NC400 to anything noteworthy? 

Your points are general, but in this specific discussion, lacking terribly.  I owned RM2, which was separated from NC400 at birth.         

Nothing prevents OP from other upgrade after amp upgrade.  Me thinks thou dost protest too much, and reading way too much into this discussion.   

[Early B.]

James,

The OP asked if he would hear a BIG difference in in sound quality in his system just by upgrading his amp. He also stated he is biamping his RM-2s with is Outlaw amp. In this configuration he would be feeding his speakers 300 watts to the low and 300 to the high end of each speaker. This is with an amp with respectable numbers, -100db crosstalk between channels, 50 volt slew rate, a dampening factor greater than 400 and a signal to noise ratio of 0.03% at the rated output. This amp is not equal to many of the better Audio grade amps available but I don’t think it is the weak link in his system.

Can his system be improved with a better amp, of course it can. Will it be the BIG difference he is looking for, I don’t think so. When I gave the OP my advice, I prefaced it with “for me” improving the source gave me a better bang for the buck (Larger perceived improvement in sound quality) than when I upgraded my amps.

I think the OP would realize a BIG difference with a better amp because the Outlaw is a weak link. An Outlaw amp might be OK for a "starter separates" HT system, but the sound quality is simply lacking for two-channel listening, regardless of  power, specs, and bi-amping. I agree that $1,500 could be better spent on other components, though. My suggestions would be to spend approximately $800 on a used Odyssey Stratos or similar price-for-performance amp and use the remaining funds (plus the sale of the Outlaw and Cambridge CDP) for a higher quality source.   

[James Romeyn]

I know little about OPs Cambridge 740c CDP.  How do folks rate it? 

[Early B.]

I know little about OPs Cambridge 740c CDP.  How do folks rate it?

I had the 640c several years ago. I would consider it entry level.

[royal]

Hey everyone, although I haven't had much to say I have been reading and thinking about all of the posts.  It seems like it may be a toss-up as to which piece to upgrade first.  I am leaning toward doing the amp first, just because I have had the 740C CDP for only about a year.  Before that I was using a Norh CD1.  It bit the dust and I needed something right away to replace it.  I was wanting to try out a computer as a source because of the convenience. I didn't put a lot of research into the purchase of the 740C and possibly made a bad choice.  Anyway, I just don't feel like replacing it now since I haven't had it long.  So, the Stratos and the Ncore both sound interesting.  Any other specific recommendations for the amp?

[Early B.]

Any other specific recommendations for the amp?

I used to own the model prior to the RM2's, and I can tell you that VMPS speakers love power. Don't skimp on power.    

[James Romeyn]

I used to own the model prior to the RM2's, and I can tell you that VMPS speakers love power. Don't skimp on power.

Datz wut am tawkn' abowt rite dare!

[mellowjammer]

I'm running my RM2s with a pair of Emotiva XPA-1 monoblocks.  In the past I have run them with a Yamaha RXA-3010 receiver, and an Adcom GFA-555 stereo amp.  The Emotivas feed 1000 watts apiece into each speaker.  I can listen to music with them full range safely as long as I don't get stupid with the volume control.  For most listening (including movies) however, I cross them over at 80Hz to keep the megawoofers from trying to eject themselves from the cabinets!  Sound-wise I still think they sounded best using my Adcom 200wpc amp (400watts into the 4 Ω Rm2s). I personally tried biamping & biwiring mine but always preferred what i considered a more balanced sound when utilizing a single input.  I have had mine since the 90's.

[Shear Bliss]

Powering my ST/R or the RM-1s with Tommy O"Briens super tasty Cherry Ultra amp. VMPS models may be rated highly efficient in db, but really come alive with a good solid digital amp. As I recall the Adcom 555 mkII had a very hot top end, midrange not much better, its forte was in the bass. Preferring it over the Emotiva mono-bloc amps tells me all I need to know ... buy American!

Feed them RM-2 with a quality amp and sit back and listen in amazement like I have been. Tommy O"s Cherry Ultra is peaches with me!

DW

[James Romeyn]

Powering my ST/R or the RM-1s with Tommy O"Briens super tasty Cherry Ultra amp. VMPS models may be rated highly efficient in db, but really come alive with a good solid digital amp. As I recall the Adcom 555 mkII had a very hot top end, midrange not much better, its forte was in the bass. Preferring it over the Emotiva mono-bloc amps tells me all I need to know ... buy American!

Feed them RM-2 with a quality amp and sit back and listen in amazement like I have been. Tommy O"s Cherry Ultra is peaches with me!

DW

Per US Customs regulation, what is "country of origin" for Emotiva amps?  I was thinking they were US made, but now can't recall. 

I have absolutely nothing against Emotiva and it's legions of rabid fans.  Obviously they are a marketing success.  I could not resist the temptation and auditioned XPA-3 with my then-Trinaural based system (replaced after six years with LCS Late Ceiling Splash stereo system).  After thorough "seasoning" for several days continuously powering 86.5 dB Dynaudio Esotec 2-way (a very neutral system overall, dead center yin-yang), Debra thought it was so hot in the mid-treble she practically leaped from the chair.  IIRC I coerced her to listen briefly to multiple software, to no avail, exact same verdict.  She was offended by it!   

In the XPA's defense, as advertised, for power hungry speakers ala Dynaudio and VMPS, certainly no one will soon be crying for more power.  Never ever approached it's power limits.  Magnitude: affirmative.  Quality: negative.  YMMV.

I remember years ago, ATI 250W @ 8 Ohm stereo power amp driving VMPS 626R...the ATI regularly was stressed beyond its limit driving 626R, which I rate as power hungry as the lowest sensitivity speakers I ever owned, late 60s Dynaco A-50.  A Carver-designed Phase Linear 400 amp drove the A50 in a San Francisco Sunset District home built circa early 50s.  On transients at high power, the amp's power meter lights would dim, as would every light in the whole house!

To think five people somehow managed to live in a 3BR/1Bath home, with only one car, a one car garage, and those cute little tin garbage cans lined with paper!  Oh, the humanity....   

     

[Shear Bliss]

Franklin, Tenn. offices but made in China ..... I too was curious on their mono-bloc amps, insane wattage and massive also. If I were a younger audiophile they may be a viable option at a modest price point. Don't think their big mono-blocks would be considered modest in cost compared to what else is available thou. Learned a long time ago wattage is nice to have on hand but by no means does it alone decide a power amps sound quality.

DW

[royal]

I've decided to have James build a stereo ncore nc400 for my RM2's.  Now the waiting begins.  Thanks to everyone for your input.

[Shear Bliss]

Royal,

Cool man, keep us up to date once you have it awhile. Your RM-2s will thank you.

DW

[royal]

Got an email today from James and my chassis is due in "about a week" so maybe I will be listening to my new amp in a couple of weeks.  This will work out nice since I just moved into my new room.  I have a detached garage that I had converted into my own living/media room.  Now I can finally play my music and movies without bothering anyone.  I'll post some pics later.

I've downloaded the following music from HD Tracks and am playing a playlist from these albums to get the sound really stamped in my mind for a comparison.  They are all downloaded in uncompressed FLAC format.  I use Jriver Media Center software for playback.

1. America - America    192 khz
2. Gabor Szabo - Spellbinder   44.1 kHz
3. Hot Tuna - Live at the Beacon   96 khz
4. Pink Floyd - Dark Side Of The Moon   44.1 khz
5. Rahsaan Roland Kirk - Krikatron   192khz
6. Steely Dan - Gaucho    96 khz
7. The Doors - The Complete Studio Albums    44.1 khz
8. War - The World is a Ghetto   96 kHz

[royal]

First, as they do on the Oscars and such, I'd like to thank all those who contributed to my getting this amp.  Wow! I usually thought before that my system sounded good.  In fact I often marveled at how nice a particular song sounded.  Now, I'm ALMOST  tired of getting the chills.   Again WOW!!   I guess in a nutshell as one friend put it  "it sounds like real instruments here in the room with us" (edit: not that I personally think it sounds completely real of course)  If it is true that, as some said here, that my source is not that good then well....   Anyway, I don't have all the high fangled sounding vocabulary to describe the effect.  I'll just give an example or two of realizing, in a bunch of songs I've heard dozens of times before, that a kind of "knocking" sound is actually a drumstick tapping against the edge of the drum, or that a high kind of "tinkling" sound in the background is actually a xylophone,  or a soft thumping is actually one of those soft headed drum sticks being hit on kettle drum.  I have a hi res recording of a live performance by the blues/rock band Hot Tuna.  Before, I couldn't pick out the bass players location on the stage (mostly very low notes on electric bass and not mixed loud)- now I can.  In fact even when all three instruments, in some trio say, seem to be standing in the center of the stage, now I can tell one is slightly to the right or left of the others.  - one last example - I always thought I didn't like classical music much until I went a couple of times to see the SF Symphony.  It sounded fantastic.  After that, I realized that it was just that the reproduction I was hearing wasn't good enough.  Last night for the first time I really enjoyed some non-live classical music.  Will wonders never cease!

I read somewhere that you should use music that you are familiar with when listening for differences in equipment.  I'm not sure why I chose to largely ignore this piece of good advice.  I was listening to a few relatively new pieces at first, and I was thinking "well, this sounds really good but I don't really know if it is that much better than before."  Things have been kind of hectic lately (moving) and I didn't get to put in a lot of listening until yesterday.   On the very first song I put on that was really familiar to me, my mouth literally fell open - no shit. And it kept falling open song after song.  I was always skeptical when people would say things like this - not so much now.

Anyway, I've rambled enough.  Thanks again for the help.

P.S.  James provided great professional service.

  Hypex

[James Romeyn]

I am very pleased that royal is happy with his new Hypex Ncore Stereo NC400. 

For anyone who might be curious about Ncore reliability: After assembling several dozen NC400, the sum total service related problem was one Cableset that was apparently defective, the symptom being one of the wire broke loose from the terminal immediately after I twisted it the same number of twists as always.  Hypex promptly shipped a replacement Cableset and all was fine.

I personally witnessed the following recently.  Someone brought over two NC400 Bridged amps (1200W @ 2 Ohm, safe to 1 Ohm) and accidentally directly shorted the two amp's speaker output binding posts (also connected to speakers).  One NC400 did not turn on, the other did turn on but cycled a click sound every three seconds till he shut it off.  No fuse blew and both amps worked perfectly immediately after he fixed the speaker wiring error.

It would not be a surprise if the above described wiring error immediately caused one or both amps (non-Ncore) to suffer costly meltdown of the amp, speakers, or both.

One client had mono blocs, and one ran considerably hotter then the other.  He eventually traced the problem back to a defective speaker crossover, which he fixed.  Besides running warm, his NC400 never hiccuped. 

Hypex NC400 and SMPS seem to be exceptionally well engineered and bulletproof.  IIRC Bruno said after about 20 years the hottest running part, the large PS capacitor, might change its capacitance value (depending on the application), but performance might not be affected in any way.  Replacing a PS capacitor after a 1/4 C seems like a reasonable service requirement.

NC400 burns 4.5Wpc while idling, less than a 5W night light.   

[klapse]

I drive my RM2s with a Yama P2500S stage amp. No fans. Low idle current. Quiet clean power. I suppose you folks think this is heresy, but I love the sound I get.

[/mp]

I love the sound I get.

That's all that matters.

[klapse]

I drive my RM2s with a Yama P2500S stage amp. No fans. Low idle current. Quiet clean power. I suppose you folks think this is heresy, but I love the sound I get.

I just auditioned an ADCOM GFA7607 amp with the RM2s. The sound is so much clearer and more detailed than the Yamaha, it is amazing.

I A/Bd the speakers with my non-audiophile friend and we both agreed, the difference is night and day!

Never again will I believe that "amps operating within their specifications sound the same". Not even close!