NUFORCE AMPS FOR PASSIVE SUBWOOFERS


I need a pair of small mono amps that I can hide behind my subs(Kinergetics SW-800), I can leave on, don't get hot and have alot of power to drive and control the six 10" woofers per side. Are the Nuforce up to the challange or should I be looking elsewhere?! I would like at least 300watts or better per channel. The subs a 4ohm. Thanks for any info!
128x128ptheo
Nice but not powerful enough for power hungry woofers. I would rather go for any of the class D using the 1000W Ice Power module (used by several high end brands in their loudspeakers with active subs).
Otherwise, you may consider a Crown MA-5002VZ: professional 1000W amp, good value for money, supposed to be excellent to drive subwoofers.
I totally disagree with Stereotaipei. The NuForce Ref 9 mono's put out 300W RMS into 4 ohm loads and can pass undistorted peaks of 650 Watts. And the Reference 9SE's put out 250 watts RMS at 4 ohms and can pass undistorted short-term peaks of 660 watts. Although the RMS rating is at your mimimum requirement, the NuForce amps sound much more powerful because of their extremely high peak-power delivery. Plus the simple fact is that the Ref 9SE amps produce the most controlled and articulate bass performance I have ever experienced.

My feeling is that you'd be very pleased with the bass performance of the Ref 9 and even more pleased with the 9SE due to it's exemplary bass control. A more powerful ICE amp without the same articulation and control would likely be less fulfilling, i.e., it might ultimately play a single decibel louder but would lack resolution/definition compared to the NuForce amps.
Sterotaipei- Funny you should mention ICE amp. I have one that is rated at 250Watts-8ohm/500-4ohm that is being updated with new speaker binding posts. I can't wait to try it when it returns. But I'm using it as speaker amp. I've owned a Crown bass amp before, Didn't impress me, no bass definition. Sold it. I like the fact about the Nufore amps that they are small/slim so I can hide them behind the subs, sizeways against the wall I plan.

Plato- I feel why the Nuforce amps have great bass resolution/definition because of the high damping factor(>4000) which control the woofers. Do you know what the 'extended bass' option is? Can't find it on the site.
I can buy a used pair of 9.02 right now for $1350. Good deal...?!
Ptheo, $1350 is a very good price for a pair of Ref 9.02s. I'd snap them up if I was interested.

The extended bass version doubles the input capacitance and results in the bass response being a bit more linear out to 20Hz. It gives the amp a little more weight on the very bottom but it's not a night and day deal. I think Nuforce only charged about $75 for that mod.

As I have stated in my other NuForce posts, I (and others) believe the amps sound best with the internal speaker post capacitor removed (which is a cheap, no-cost tweak). You can snip one capacitor leg just to try it and solder it back in place if you think the cap makes it sound any better.
300 watts ain't much for subs...

Crown K1/K2. K1 is 1500W bridged @ 4ohms, K2 is 2500W bridged at 4ohms.

Damping factor is right up your alley at >3000, although personally, I think that spec is not TOO important.

They are small for their power because they are a "digital" amp, but they are not miniature by any standards. If you are looking for great performance in a sub amp you should investigate these.
The K1 Destroys the Nuforce, no joke... It is a pro unit, no fan, barely any heat, and can be driven way beyond the input voltage and has a 28 db setting, 1.4 volt setting, and bridge Switch...Can take full boosted output of like 20 db gain from a parametric or other processor, especially pro units that can do this. I picked one up for 400 used, it is a very similar to digital design, I swear I did see a module inside the Crown that had ICE written on it, but not to mention it only idols pulling 12 watts from the wall, it is All U.S.A built, and dead silent, ZERO FM interferance problems, Zero Hum, Zero HISS... On 98 DB efficient drivers.. Now I have heard the nuforce standard versions, they will not hold up to the crown.. But the Crown has a Huge Torroid and Way Higher Peak power for way less money, and again it is a pro unit designed for a good beating, has built in limiters, and Has Individule Detent Gain Controls for each channel so you can taylor to your liking. Only problem with them is the Binding posts are rediculously close on the back and a little tuff to hook up without using a Quarter to tighten them up, and you will need to have RCA to Balanced cables if you are running RCA.. You will not hear the Crown K1 Click, Pop, or Hum when Turned on, it will not Dim the lights etc... Not to say the nuforce will, just giving an Idea of the quality in this unit. By the way the Crowns are Stereo, but if you must have mono blocks to seperate across the room, than well you need 2, otherwise go with the nuforce, but seems to be a waste of money for Subwoofer bass.
I've owned the Crown K1 and used it on my Apogee Studio Grand subs. Didn't like it. It had plenty of output, but no bass definition. I thought it would be the ultimate amp for my subs, but I was wrong. My Classe 201 amp smoked it but runs much hotter. I want a amp(s) that I can leave on 24hrs and not worry about heat/power consumption. Thanks for the Nuforce info Plato. Looks like 9se's are the ones to get! I just ordered a Velodyne SMS-1 so I need to find some power for my Kinergetic subs soon!
Give EarthQuake Sound in Hayward, California a call and see if they'll sell their plate amps separately. You'll have a high pass filter and gain control with low and high level inputs, little to no heat, and signal sensing auto on. Nice folks and great service too.

I agree with Ptheo regarding Crown's K series. I used one in my electric Bass rig, which includes a Bag End sub that needs 400 watts max, simply poor low level definition. For Pro amps check out Crest or QSC, I believe they're both making fan-less models.
Interesting on the K-series.

The two negatives are in contrast with what many others using them seem to be saying and in contrast with my own experience.
Whoaru99; In an effort to qualify my comment I can only offer simple comparisons. I'm currently using a Velodyne DD 18 in my two channel system, an EarthQuake Super Nova 15 ( dialed in using the Velodyne program) in the HT setup, QSC PLX 2402 driving a Bag End ELF-M / S18 E subwoofer and a D10 BX for stage Bass amplification.

Before purchasing subs for the audio systems I would frequently use the Bag End system at home. During that time I had the opportunity to use amplifiers from Crown ( K and Macro series ), Crest, Yamaha, Eden, Carvin, and QSC, in both stage and audio applications. While all the amplifiers drove the sub only the Macro, Crest, and QSC could reproduce accurate tone and fundamental from the B string of my Lakland 5-94. The K would shut down often during a live performance and had a noticeably thin sound both on stage and at home. On the other hand the Macro preformed well but it's size, weight, and the poor service Crown offered with regards to the K kept it out of my rack. While low bass is not as abundant in an audio application as it is when playing a five string bass, the definition is still obvious.

A driver/cabinet unable to resolve a flat signal into the low twenty's as well as a room too small to handle the wavelength produced by such a cabinet can easily mask an amplifiers ability at this low level.

I am in no way questioning your experience with this product. If Crown's K series amp is working for you that's great, they're economical and abundant.
I have SW800's and drive them using a Kinergetics KBA75 (100w Class A). If you want something small to hide behind the subs, look at the Meitner MTR101 mono blocks. BTW, how did you decide you needed at least 300 watts?
Vicdamone- Thanks for the suggestion, but I don't need an amp with any 'high pass filter and gain control with low and high level inputs'. My Lexicon pre/pro does all that. I just want a power amp only. Looks like you really know your bass!! (I HAD two Velodyne DD-15 subs and as much as I tried with the EQ/RTA, I couldn't get them to match with my Apogee's. They seem too restricted and not musical. Movies were great(although I hit their limit) but music comes first. Sold them.) Any cooler running/high damping sub amp brands for me to try?!

Jim- I want to start a thread soon about the SW800's because I have ALOT of questions. But stickin' to this thread:
1) The SW800 subs I just bought a month ago from a local Audiogon member have 6(SIX) 10"-woofers per side. Which I have never seen before and they have no serial #'s on them.(Custom?) So, 100watt amp divided by 6 woofers=16watts each. Not going to cut it, no way. BTW they are 4ohm, so 32watts. Still not close enough. I would like at MINIMUM 50watts per woofer. 50x6=300watts. Optimal, 80x6=480 QUALITY watts.

2) When the sw800's originally sold new they came with Kinergetic 500watt monoblock sub amps. That was with 5-10"(not 6 like mine) woofers per side. 5x100=500watts.

3) I have a workhorse Adcom 5800 that puts out easily 250watts per side. It rocked every sub I have tried with it. I used on the SW800's, the woofer suspension barely moved even cranked up! 6x41=246watts. No way Jose, not enough power.

I the meantime I have a second Velodyne SMS1 coming in two weeks to run them in stereo. By then I will have my H2O ICE amp back to try that on the subs! I love this hobby! : )
I forget the model designation, but Tony did produce the SW800's you describe as a later series -- not a lot of them around. I forgot the details of our conversation about them, but I recall it being an aesthetic thing -- the 5 driver SW800's we5re designed to be the same height as the CLS on spikes. The taller SW800 is the same height as the CLS on the dedicated Arcici stands. The original SW800 amps were combined with the crossovers, so there were actually two crossover/amp units in the system. The single SW800C Platinum crossover and the KBA75 are working very well for me. I can shake the house and rarely get the crossover volume control near its max.
I personally am not familiar with it, but what about one of the new UCd700 module based monoblocks from DIY cable as a possible contender as well.

Mike