First Watt M2 new addition to the family
 

I just hooked up my demo First Watt M2 from Reno Hifi. Really a nice sounding amp. I'm using my Inspire LP-2 tube preamp and either a Rotel RCD-1072 or Cary 308T source. I was having trouble controlling the bass on my Zu Omen speakers with my ~10 wpc SE tube amp, as the 12 ohm load was proving to be a challenging fit with it - some stuff sounded great - but music with big transients and bass just didn't make it. Lots of saturation/clipping. I probably should have sprung for the 8 ohm Zu Def model, with the higher efficiency at 101 dB/w.

Really happy with this First Watt M2 amp so far! It's just one night, but no regrets. Nelson's description of the M2 as the solid state amp for tube fanatics is spot-on from what I'm hearing. :banana:

Looking forward to hearing more about your experience with the M2. Nelson Pass is a creative genius when it comes to designing amps.

Hi Aercool,

Fancy meeting you here! http://smiley.nowdararpour.ir/other5/13.gif

I've been wanting a First Watt for a while. I'd love one of those new SIT stereo amps, but not about to spend the money.

Did the M2 take care of that problem Lucinda Williams track? If so, I'd be quicker to blame your Zu's than the amp. I'm powering single driver Omegas at 93db sensitivity and at 5wpc or so with the Pope 6V6 power tubes. If I recall, you've been running 6550's which should give you twice the power. I didn't get the bass clipping on that track at all.

But you've got a potential solution there with the First Watt. It's a push pull, so I've been hesitant about it. I'd love to hear more about how it compares, in the various qualities we like to talk about, with the Inspire.

Yes, the FW M2 definitely handles the bass better. I readily admit that the Zu Omen and their odd 12 ohm impedance may be the problem. Hindsight being 20/20, I'd probably spring for the Zu Defs which present an easier 8 ohm load and 101 dB/w efficiency. However, the M2 controls them well and the LP-2 preamp warms the sound nicely. The Inspire plays louder than the M2 - a 2 or 3 o'clock listening position on the LP-2 & M2. Noon or 1 o'clock was the norm with the LP-2 and Inspire with vintage Tungsol 6550's. The M2 has more than 2x the power, but Dennis' amp has more real output. I'd say the Inspires are "conservatively rated".

That said, Nelson says the M2 is for tube amp lovers - and so far I tend to agree.

Sounds like a good one. Sometime I'll get to hear one. I'm surprised that the output is lower with the M-2. But I don't think gain is directly rated to power. I don't understand it well enough without referring to something though.

Look at the N.P.'s table of First Watt amp specs: http://www.firstwatt.com/prod.html. The M2 is more powerful than the SIT-2 but has less gain.

The difference you see in volume settings is not at all indicative of power output capabilities. It merely reflects the amps' difference in sensitivity (i.e. gain). In some cases you may not have enough gain in your preamp to hit a given amp's max rated power, but that's pretty rare unless you're running a very low output source (e.g. a low MC without enough phono stage gain).

Tube amps in general seem to have fairly high sensitivities for a give power rating; perhaps a holdover from the days of low voltage sources and lower gain preamps. Solid State amps seem to be less sensitive, as if they've got hot digital sources in mind. I once had a vintage Eico HF-87 EL34 amp that had something absolutely ridiculous like a paltry 0.38V input to yield +3dB over the max continuous power rating. A 1V or 2V input to yield max rated power is more typical.

I'm a tube lover who loves his 250 Watt tube amps, but I've recently re-learned how to love quality sand. Those First Watt amps are mighty intriguing.

Your M2 will almost certainly go louder before hitting clipping; you'll just need to turn the dial higher to do so. Ideally your system components will not have more cumulative net gain than you'd ever use -- i.e. you don't want to be penalized for the signal/noise ratio hit from active gain you won't be using.

Thanks for the clarification mulveling!

I had a really good night with the First Watt M2 + Inspire LP-2 + Zu Omens last night. Between Lucinda's new one (hard to get those discs out of the player...), Emmylou's "Wrecking Ball" and a couple of Steve Earle ("Jerusalem" and "Washington Street Serenade") things were sounding grand. It could have been the fine Bohemian Pilseners I was quaffing, but the soundstage was wide & deep and everything was sounding 'right' to my ears.

Ever subject to the upgrade bug, I have a First Watt J2 on the way to see if the higher gain from that amp suits my system even better. If not, back it goes - no harm, no foul. The J2 gets rave reviews with its JFETs (vs. the MosFETs for the M2) so I'm excited to audition it.

Peter - out of curiosity, what is your source component? I'm still perplexed how the higher the output voltage, the worse the overload sounded with the Inspire amp+preamp all tube system. e.g. a Resolution CD-55 with it's 3.5v output sounded horrid, a 3.0v Cary CDP sounded pretty bad, but my humble 2.0v Rotel RCD-1072 sounds the best of all. I was never able to engage Dennis on this dynamic and see if he could replicate it in NC.

Hi Mark,

My source is a Cambridge Audio Stream Magic 6. Basically their NP30 streamer mated with a DAC Magic Plus in the same chassis. They don't list output voltage in the SM6 specs, but the max output voltage for the DAC Magic Plus is 2.1V.

Since I am using the LP-2 for a pre-amp, which has no remote volume, I use the SM6 in preamp mode so I can control volume from there. I would guess that means something lower than 2.1 Volts most of the time.

I don't know enough to speak to pros and cons of input voltage to your preamp. But I could see where something higher than the pre is designed for might compromise sound quality.

My money is on the J2 as your preference over the M2. I look forward to reading how it goes. You are trading some negative feedback to get single ended and additional gain in the J2. Coming to the Inspire KT150 after a couple of conrad-johnson push-pull pieces, I'm sold on the single ended design. I now also don't worry about power output. With speakers 93db and up, a few watts is fine. Compromises have to be made for more power than that - in tube amps anyway. I'm not sure how that applies to solid state.

After comparing the M2 and J2, return one and get the SIT-2 for comparison. That design seems to have it all! :cool:

I also think the J2 is probably the one I'll end up with, but couldn't pull the trigger on solid state at the $3k price point without working my way there by listening to one of Nelsons designs via the M2 (less than half that sum). Back in the late 90's I was always intrigued by the Pass Aleph amps, but never bought one. I was wildly happy with my Ayre V-3 + Cary/Audio Electronics AE-3 combo, and figured I needed more power than the smaller Aleph 3 with my inefficient 87 dB/W speakers at the time.

I was REALLY happy with the M2 the night after I pulled the trigger on the J2, so it needs to be a step-change better to justify the upgrade cost.

The SIT-2 does look interesting, it was a close 2nd to the J2. Lots of gain from that design with only 10 wpc!

I'm planning on having the best of both worlds. With nice speaker interconnects with banana terminations at the amp, it'll be easy to swap between the M2/J2 and the Inspire KT-6550/6V6/etc. I already love them both, and for different reasons and different music sources. :banana: