Nuforce step up from Sunfire for B&W 803N?

Have Sunfire TGA5200, which does 5 x 200/400wpc into 8/4 ohms, powering B&W N803. Looking at adding separate 2 channel amp for possible SQ upgrade for fronts. Is the Nuforce 9v2SE for the front two channels an upgrade? It's only rated at 190/300wpc but obviously power isn't everything, and I've heard that it has awesome bass and great clarity. However, the disparity does concern me a little as the N803's really need stable power into 2-3ohms. Would pair with tube pre, which I'm also looking into to upgrade over HT pre/pro. Just to add one more clarification, if anyone starts adding other amp suggestions, amp needs to run cool and be less than 5" high, which kind of limits me to Class D. Thanks much...Jeff
It's only rated at 190/300wpc but obviously power isn't everything...
Jeffkad (Threads | Answers)

Doubling power as impedance halves is sometimes everything, especially when the speakers being mated have significant impedance dips and spikes. The N803 impedance dip to 2-3 ohms should be a concern.

This should be considered when matching speakers to the NuForce Ref9V2SE.
The Sunfire can put out a little more RMS power than the NuForce at 4 ohms, but since the Ref9V2SE can pass undistorted 650-watt power peaks the NuForce will actually sound louder when playing music. If you're playing a sustained note the Sunfire might do better, but most of the music I listen to has momentary loud peaks, which again, the NuForce would likely handle better.

As you dip the impedance then the NuForce gets even better as it is able to provide 1300 watts of short term power at 2 ohms and can even handle loads below 1 ohm. The bottom line is that when playing real-world music the Sunfire has no real advantage. Realistically, either amp will provide enough power for the 803N speakers but I have a feeling the Nuforce amps will sound better.

Also, the NuForce 9V2SE sounds great with a good tube preamplifier and that is how I'm using mine.
I auditioned the Ref9V2SE with speakers that are 8 ohm nominal, but have dips below 5 ohms.

Compared with amps that double power as impedance is halved, the NuForce amps produced unbalanced frequency response that was light in the bass, resulting in a tipped up sound.

Otherwise the NuForce amps sounded very good.

They are worth an audition. Just pay particular attention to tonal balance on the B&W speakers.
Thanks for responses so far. As I step up in the world of hi fi, clearly there is no perfect fit. I am very happy with the sound of my setup, but I've caught the bug and am now looking to make it even better if I can within my restrictions of low heat and smaller size amp chassis. I am trying to figure out what I would like to improve in the SQ, and one thing is the visceral impact of bass (organ, kettle drum, etc) and the sharpness of the "thwack". Hence my concern over power, although I've heard that the nuforce has great damping which also contributes to tight bass and may improve the areas I've mentioned above. I may want to smooth out and separate instruments some overly bright or dense recordings, although I'm splitting hairs here. In fact, this may be more a preamp issue, but I'm thinking the bass is an amp issue, no? Another thought is the Spectron. Still interested in Nuforce vs Sunfire opinions too though.
Jeffkad, the NuForce amps are available with an essentially no-cost home audition via the NuForce Demo program (you pay for shipping). Why not try them for yourself?

The bass impact issue is one that might be affected by the power output specs of the NuForce Ref9V2SE, but you should hear the combo to decide for yourself.

The Spectron amp doubles power output into 4 ohms, although it does not double again into 2 ohms, but nevertheless it will likely produce better tonal balance on your speakers than will the NuForce, IMO.

If you're looking predominantly at chip amps, you might consider the H20 Audio monoblocks (which are also available with a home trial). These amps also double power output as impedance is halved.
Tvad, thanks so much for your responses. Not sure what you meant by "The bass impact issue is one that might be affected by the power output specs of the NuForce Ref9V2SE". Did you mean affected positively (more impact) or negatively (less impact). I inferred the latter, but want to be sure. As for in-home, I'm really looking at used purchase. A combo of used nufore and a tube pre like Dodd, Modwright, etc, brings me in at 4.5k or less, which I can live with. Actually, would never buy amp new in this mkt, as depreciation is so favorable to used buyer. Now, if I go with the Spectron, that kills my budget for a good preamp. Of course, maybe I should get preamp first as that may have bigger overall impact, but I'm still sorting all this out. Right now, trying to clarify what the nuforce might bring to the table vs the sunfire, and/or if their are other options. (Wish I had room, money and house current to get a Plinius Odean or Simaudio Titan!!!).
03-02-09: Jeffkad
Not sure what you meant by "The bass impact issue is one that might be affected by the power output specs of the NuForce Ref9V2SE". Did you mean affected positively (more impact) or negatively (less impact).

I meant negatively due to the fact that the NuForce will produce less volume in the bass frequencies relative to the mids and highs, therefore potentially resulting in a presentation that lacks bass weight and punch as compared with some other amps that we've discussed.

I understand wanting to buy used. I've done it myself for five years.

However, before you dismiss the idea of using the NuForce home demo program, take the time to contact a NuForce dealer. You might be surprised at the possibilities. I know I was.
...or buy a used pair of Ref9V2SE and try them. Keep them if you like them, or resell them if you don't.

There's no universally correct answer for which component will be best for every system and every listener. There are better choices based on electrical specs, but even these can be tossed out the window based on a listener's personal preference.

At some point, you have to dive in and do the listening in your system with components that interest you.
Tvad, you are absolutely right about the diving in part. I've been researching preamps for some time and have been waffling between Dodd, Modwright 9 or 36.5 and now the new Isabella from Red Wine (although no HT passthru, as well as VTL and BAT. Man, it's hard to make that decision, and it may just come down to what's available at a good price on the gon. No used 36.5's or Dodd's or Isabella's right now, so I'm kinda holding tight. As for the Nuforce, yeah, I did try to reach out to one seller but he never replied. However, starting to think the Spectron may be the way to go, but it's a lot of cash. For goodness sake, all I want is some bass slam, tight but visceral bass, crystal clear highs, shimmer and sparkle, and all those great "tube-like" qualities I've been hearing so much about like presence, you-are-thereness, air, musicality, like you are in the middle of the stage. And all for around 4-5k. Why can't this be easier, LOL?!?!?
Good luck.
Ha. I assume that was facetious?
Not really.

It takes some luck to buy-and-try, mix-and-match used gear on Audiogon if you're going to buy gear based primarily on what's available at a good price, rather than on what is known to have proper synergy.

Sometimes the saying, "buy again" is brutally true.

Believe me. I've been there.
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Tvad, I hear you, but the synergy issue is exactly what I'm trying to establish by dialogue on and reserach of these boards. It is clear to me that there is a good synergy between Class D like Nuforce/Spectron and tube preamps like Modwright (and possibly Dodd, etc). Once I've seen a pattern that seems to work, I put that on the list. As for price, I'm simply trying to get one of my preferred candidates (synergy established by consensus), and buy at used vs new price so I can maximize my budget. I think that approach makes some sense, no?
What I am trying to establish here is whether the nuforce, etc is a step up from Sunfire. I've gotten conflicting signals so far (including a few PM's), so I may just have to take the leap on the Nuforce and see what happens. However, if I buy it at used price, I lose little if I don't like it and have to sell. Also, it allows me to keep the Sunfire while I audition the Nuforce. I think I'm also going to post a new thread asking whether (if I had to choose one) upgrading the preamp or the amp would make the most difference. Tvad, thanks again for your continued interest. BTW, what system are you running?
Eric, that's very interesting. Don't know how the PSA compares to Nuforce or Spectron, but it seems like the latter have gotten far greater number of rave reviews, so maybe they are better. Don't know, but as Tvad says, I just have to jump in.
Jeffkad reading your thread Tvad gave the best advise, you can save your money buying used by getting a loner from Nuforce to audition most are broke in so that would not be a issue and you could hear if thats the amp for you.

I've been using Ref 9 SE V2s driving Tyler Linbrook Sigs. The impedance at 4 rated ohms is not steady and makes your amp work hard. It appears that your B&Ws are similar. To compare the two i haven't had any issues with my Nuforce amps and most of my listening is classic rock at high DBs. Thats not to say you will be satisfied. Also i use a tubed preamp in the sound chain. Hope you get connected with a amp that pleases you time is a wast-in.

BTW i do understand your thought of having a 2 channel dedicated system. Surround sound only can take you so far. And if your 2 channel system is set up right you get surround sound.
FWIW, when I auditioned the NuForce amps, the price the dealer offered unsolicited when I was ready to return the amps was less than they were selling for used on Audiogon.

No, I won't disclose the dealer's name.

This is my system:
Silverline Sonata III loudspeakers

Pass Labs XA-60.5 monoblocks, Lamm L2 Reference preamp, Heed Quasar Phono preamplifier

APL Denon 3910 Universal Player, Music Hall 25.2 modded by PartsConnexion as a transport, KAB Technics SL1210 MK II w/Dynavector XX2 MK2, KAB Fluid Damper, KAB Cardas Tonearm Rewire, KAB Power Supply
Squeezebox SB3 wirelessly connected to MacBook Pro

Purist Audio Venustas RCA ICs, KCI Silkworms ICs, Oyaide PA-02 balanced ICs, Gregg Straley Reality Cables bi-wire speaker cable

Power Cords:
Oyaide Tunami GPX power cables (amps, digital transport, phono preamp), Tekline Reference PC (APL Denon 3910), BMI Hammerhead MK II (preamp)

Two 20A dedicated outlets, Environmental Potentials EP-2050 whole house AC filter/surge suppressor, Alan Maher Designs Reference Power Center V2

Stands, Isolation, Coupling:
Salamander Synergy Cabinet w/ sorbothane treated shelf supports, Sistrum SP-101 stands under speakers, Timberation 2” maple platforms w/Mapleshade 2” brass cones under amps, Neuance isolation shelves for digital source, preamp, and preamp power supply, Galibier Design/Timbernation sandbox under turntable
I love my nuforce amps, they are really really good you will be very happy with them. They will find weaknesses in you system if you have them. If you demo them be sure to demo the Black Noise Filters model(2500) with them. They make the amps even better. You need to leave the amps on for at least a week to really get the sound and they must be broken-in.
Well, went for a preamp first. About to pick up a Rowland Capri and see what that does for my system. I have noticed lately some hum and crackle from my mids and tweeters. Not sure if that's just low level amp noise or what. Also, have a little glare/harshness I'd like to get rid of. Starting to wonder which component is the culprit: B&W N803 (some history of this), the modded Denon DVP, or the Sunfire amp or pre/pro. First out, the pre/pro, to be replaced by the Capri. If that doesn't work, may try amp, then DVP. Otherwise, I may have to question the B&Ws, which I thought was the one thing I would never have to change. Hopefully the Capri does the trick.

Is the Capri the answer to your prayer?

Please share,

Sorry, haven't been around for a while. Kenobi, actually no, the Capri hasn't been the answer to my prayers. It sounds perfectly fine, and over time has begun to sound slightly better than the Sunfire pre/pro's "source direct" mode (it's best equivalent to pure analogue preamp), but it is not a huge, or even moderately big difference. I am somewhat disappointed that 4k (1900 used) in standalone preamp did not make an appreciable difference. However, I spoke to an audio mag reviewer who said that the preamp performance is being limited by the Sunfire amp. I've just picked up a pair of Nuforce ref9v2SE mono amps, so we will see if that's correct. The Capri is just an exceptionally well made piece though. It's just beautiful, and works so smoothly and flawlessly. It also allows me to compare it directly to the sunfire by using the bypass feature. We shall see.
As for the harshness, it just isn't there on well recorded jazz albums, my primary listening. It's there on bright recording, ie, Phil Collins, especially his horn section. Might just be good audio equipment revealing poor recordings. I must say, I've been enjoying the heck out of my music and SQ lately, as I stick with good recordings.
Hi Jeff,

Thanks much for your feedback regarding the Capri. It'll be interesting to hear the paring with the Nuforce Ref 9SE V2 as I have the MCH3SE (multi-channel equivalent to the monos). I think the Nuforce will give you better clarity, transparency and extension on both ends of the spectrum to say the least and it is ultra-fast and starts and stops on a dime. I would not use analytical cabling with the Nuforce however. Something slightly warmish will balance out its intrinsic detailed nature and gives a fuller picture.