FirstWatt SIT-3 or Pass Labs XA25 for Avalon Indras?

You should read the recent thread about the Fletcher Munson effect and low volume listening.

Haven't heard or even seen the SIT-3 but have listened to the XA25 vs a Bricasti M25 and no contest the Bricasti just sang. The XA25 sounded strained and sterile in comparison.

Power isn't just for loudness. It's for fidelity. Even at low level on some music peaks can be 20 to 30dB. To play them accurately you need tons of power.

P.S. The comment on Fletcher/Munson also applies. Our ears are flat around 100dB. Bass is way, way down at 80 dB which isn't quiet after all.

Munson was a catcher with the Yankees.  Not sure why his curve keeps coming up.  

Check out Pathos amps since it is in your neck of the woods!!

https://pathosacoustics.it/en/non-inpol-amplifiers/

The Pass X25 sounds is amazing when I heard it with Tekton monitor impact. The Tekton are at least 92 db.

Hi Alberto,

Suggest you read the stereophile review from Herb Reichert if Jan 2019if you have not done already. The choice of speakers is very important as they suggest. This is why I went with the XA25 since I have Harbeth 30.2. Another consideration may be resale, if you need to change later on. Ir if you change speakers. The XA25 would be more versatile or easier to sell iIMHO.

I’ve owned the XA25 twice and tried it with a variety of speaker loads.

IMO, the amp does not excel at low listening levels, nor does it drive low impedance loads very well. It is a sweet sounding amp with great soundstage, but it really requires careful speaker matching to bring out its best. I wouldn’t want to use it with any speakers of <90dB sensitivity and <6-ohm nominal load. Also best if the speaker’s impedance has mild phase angles.

I realize this largely contradicts the claims made in the Stereophile review, but that just goes to show (IMO) the misleading tendencies of such publications. I get they often have to walk a fine line between praise and criticism, but I wish they’d be a more forthright about component limitations and synergy. Claiming that the XA25 can adequately power Magnepans for example, ultimately does nothing more than a disservice to both Pass and the consumer. The more experienced I become in this “hobby”/industry, the less I pay mind to the claims in these magazines.

The Coda No.8 (any version) will give you much of the same sound profile as the XA25 and sound way more authoritative at low listening levels with your Avalons.

Others I recommend considering are the Yamaha (yes, for real) A-S2100 or 2200 integrated amps. I owned the 2200 (currently own a 2100) at the same time as the XA25 and concluded it was overall sweeter/lusher (more similar to a SET amp) than the Pass, and like the Coda, sounds far more effortless at all listening levels. My experience is that both those Yamaha integrateds marry most of the strengths of tubes and SS, and can compete well against any separates combos I’ve compiled under ≈$8K retail.

Anyhow, the two amps you’re considering would probably be two of the last I imagine would pair well with Avalons.

"@ulul Power is not the key point, if I listen to music during the day the knob never goes beyond half of the current power amp ... ... The aim is to have magic and involvement at low volume."

Others here have already mentioned something similar to my own experience. Another .02 cents to add if it helps.

After messing around for too long over a few decades between my former 87db 4ohm and 92db 6ohm speakers, trying and owning several capable solid state and tube amps, the part about listening at "low volume" with lower current / lower power amps can be challenging to achieve for what I think you are looking for here from the sound. Sure the lower power and lower current amps will play, nice and smooth. However if that’s all you are looking for, may be good enough. Now room filling sound, that’s another thing at lower output levels. Learned this the hard way.

If you are planning to keep your existing 87db 4ohm speakers, and if filling the whole room with sound at Low listening levels, I’ve just found my traditional higher current / higher power SS amps with a little more weight to the iron and power can help. Yes, particularly at low level listening levels is what I’m getting at primarily.

Later I stopped fighting it and sold my lower efficiency 87db 4ohm speakers in order to try different lower power amplifiers again. With that said I still enjoy a tad more current/power with weighty transformers in the amps and one of those I alternate with now is only a full-time Class A 50w modified Pass amp btw. It does well for its power and size, yet when I jump to my 120w mono tube amps with double the iron, my 92.5db 6ohm speakers just sing that much more at low, medium, or high levels. Hope that helps, maybe look at something with a little more current/power/drive as others mentioned here for your Avalons. Best of Luck.

Thank you for these useful experiences. Has anyone listened to SIT3?

Between the two hands down the XA25, not even close. I have heard a few SIT amps and they sound best with higher efficiency easy to drive speakers but they were too fast paced and uneven sounding as a system. The SIT3 only has 11db gain which is extremely low and may sound anemic with typical gain preamps. Even the XA25 sounds best with higher gain preamps- e.g. 20db or so.

The SIT3 only delivers 8 watts at 8 ohms before it starts to clip, unless you have a small room, listen close to the speakers and like moderate volume listening cross that one off of your list.

I have owned the XA25 and with my speakers which have a similar impedance and sensitivity to yours the sound was excellent, one of the best sounding amps I have heard or owned.

It has almost twice the gain as the SIT3 and starts clipping at 90 watts per channel despite it's 25 watt rating.  

In addition to suggestions above, if you still have interest in Pass design, look up reviews of the SIT 4, particularly a video of Steve Guttenberg (SG), a stereo unit, due for release in mono block --twice the power. SG suggests "notably more powerful sound than specs suggest". Of course there is only one way to find out. Enjoy the search.

I own both the XA25 and SIT3 but can’t add anything meaningful to the conversation because I don’t know your speakers.  My speakers are all 8 ohm and high sensitivity and I use multiple subs so low level listening is very enjoyable.   These are quality amps when system matched properly. 
 

@whiteknee "These are quality amps when system matched properly".

Exactly. And yet the OP keeps asking about the lower powered SIT-3, regardless. The more operative question would be has anyone heard SIT-3 paired with your 87db 4ohm Avalon speakers. I’d venture to guess most likely not as it would not be a recommended match and pairing. Proper amp-speaker matching makes a real difference.

ulul

I've never heard any First Watt amplifier, so I'm no help there.

I bought a "lower" power solid state amplifier earlier this year (a CODA S5.5), if you can find a dealer near you to demo one, I think it would be worth your while.

50WPC pure class A, more in A/B; 100 amp current delivery, and in my system (Aric Audio Motherlode XL driving: vintage Infinty RS Kappa 7s, Buchardt S400 MKIIs, Clayton Shaw Caladans, and Thiel CS 2.3s. It is stellar with each speaker, and the Infinitys and Thiels are not easy speakers to drive. I also do not listen at loud volumes, and love the presentation at "reasonable" listening levels

As you may know, CODA's Doug Dale and Eric Lauchli were with Nelson Pass at Threshold, until Nelson left to form Pass Labs and later First Watt.

Worth a listen if you have a dealer within driving distance of you.

avanti1960

SIT-3 at 8ohms delivers 18W not 8W (30W at 4ohms).

@ulul

Per the Stereophile review of the SIT-3 they measured 8.4 watts at 8 ohms when it started clipping. I had been interested in Forst Watt amps. If you must try one, the J2 would have the best match with your speakers.  They often come up for sale. Good Luck,

First Watt SIT-3 power amplifier Measurements | Stereophile.com

Hate to be the bearer of bad news but your Avalons have a reputation for being power and current hungry. Either of these Pass designs would leave you wanting, especially at low volumes. I have little doubt that even Nelson himself would tell you something similar. 
 

Pass makes some fine amplification, but so do many others. You’re better off trying a higher power Coda or Ayre amp. The XA25 is rated at 25 WPC for good reason. Certainly, it can output more before it reaches “clipping” at 1%THD, but it clearly sounds strained when doing so. It simply isn’t a high current design, neither is the SIT-3.

The best advice I can give is to cancel the Stereophile and TAS subscriptions. Those pubs survive off of keeping audiophiles on the merri-go-round. Some of the most underwhelming gear I’ve owned and experienced was praised by those rags. 

@ulul 4 Ohms isn't a good load for the SIT amps and is marginal for the XA25. These amps are not high power and really are much better suited for slightly higher impedances since they tend to run warm- lower impedance loads (like 4 Ohms) will make them run warmer.

There are class D amps now that have every bit the quality of sound you seem to be looking for, but no heat (and unsurprisingly) more power. You might want to consider widening your search.

Go to Powermodules.com and get a Belles Amp...I have the Aria Integrated rated at 70 watts @8 ohm...It would drive the A's nicely.

Or call Rich @ Signature sound in Liverpool, NY.

I have both the SIT-3 and the XA-25. The XA-25 is sitting in a box... but it depends on the speaker. I'm using it with my Klipsch speakers. If I owned a set of Harbeth's my hunch is the SIT-3 would be in the box. Unscientifically I'd say the XA 25 with dark speakers and the SIT-3 with breathy horn speakers.

At the end I bought a SIT-3, which I listened to several hours between last night and today. 
Well, the first impression is that it is darker than the Bartolomeo Aloia Micropal that now sits on the couch, but also that it has no problem driving the Avalon Indra in the room (3.50mt x 5.50mt with a maximum height of 5.50mt), the armchair from which I listen is 2.5mt from the Avalons. 

One curious thing about volume/power and gain. At realistic natural volume (equivalent to the volume at which I would hear a piano in a concert hall in the fifth row), I had to turn up the volume of the preamp by 20%, and this seems normal to me because the SIT-3 has low gain and the Aloia is a bit more powerful. 
But the curious thing is how perform at very low volume (at 2AM at night I can't disturb the neighbors sleeping on the other side of the wall). Well, to get the same volume as the previous amplifier I had to turn the knob much less than the Aloia. It is as if at low volume the SIT-3 has hidden power as if loudness is engaged. Not only that but at low volume the bass makes the music come alive. 
This surprised me a little and I liked it.