First Watt SIT 5

I have a SIT4 on order, planned to arrive in the next couple of weeks.
I also have a Yamamoto A-09s (300B), Air Tight ATM-300R and some 211-based SET monoblocks to compare them with the SIT4 on my 99dB speakers (horn-based with large woofers).
Adding to the above. I have past experince with FirstWatt amplifiers. A decade ago I bought the J2 for a different pair of horn speakers I've owned back then.
Eventually I preferred a set of 300B Audio Note (UK) monoblocks to the sound of the J2.
It sounded too "solid-state" for my tastes.
I hope the SIT4 does things differently.
 
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It is the best amp ever (so far that I've heard) and you'd be a fool not to buy it (after talking to Kent about the speakers you have).

Reading thru the FW manuals, Nelson leaves thoughts about various things, including how various amps might compare to one another for help with how it will work / sound.

He is very modest and does not brag. He chooses his words very carefully, and if he says some of his amps sound like triode tubes, it is worth noting. He lets others brag on his amps.

Below is from the F7 manual, and it's where he more or less says, with more clarity than I have seen elsewhere "these SIT amps sound like triode tubes"... (or better).

View attachment 157259
Haha. Perfect! John is on vacation so I will order next weekend or the Monday after. I will probably speak to Kent and John one more time prior to ordering. The int-25 will help the space issue. Not sure if one will be more versatile as far as playing different genres of music. Very happy you are loving the sit-5. I look forward to satisfaction without tubes in my future!
 
Hi Hubert
I do not have the SIT 5, I own the SIT 4.

I was tempted to buy the SIT 5 based on its monoblock configuration which was my preference. I did not need the extra power provided by the SIT 5 over the SIT 4 with my Cube Audio Nenuphar speakers with their 91dB/watt efficiency. I also read that the damping factor or 2 with the SIT 4 is better suited to the Nenuphar's.

To answer your question, I had a loaner SIT 4 for three weeks until last Tuesday when my unit was finally delivered. The loaner was the demonstration unit used by the retailer and had at least 6 months of regular use so I think we could assume it was well run in.

I turned off the loaner at 6 pm on Monday night and had the new unit up and listening at 12:30pm on Tuesday. I played my usual demo tracks to hear how it sounded and I could detect no difference in sound quality between the two. From my timeline, 18 hours had elapsed between auditioning both amplifier, so it was not an immediate A/B comparison but as close as I will ever get.

I did notice a difference (improvement) in audio quality after 30 minutes of use on the new unit.

After owning EL34 & 300B SET ampilifiers for 40 years, I am definitely not a "burn-in denier/denialist" and I suspect that components such as capacitors & valves (tubes) did improve with time, but then, I could just be imagining it. :)

My above auditioning experience with the loaner SIT 4 vs. the brand new SIT 4 is the first time in my audiophile career that I have come close to a true, controlled experiment on the theory of component burn-in. Of course, my slightly flawed comparison was based on this amplifier only. Other component may quite well benefit from burn-in.

If the delivery person had had more time and I had had the opportunity to do a direct, double blind listening test with a panel of recognised audiophiles (with their latest audiograms) then I could have provide a more definitive answer. ;)

Gary:)
Thanks Gary!
 
Congratulations. Look forward to hearing your impressions.
Thanks Earthbound,
It's hard for me to properly evaluate the SIT5 distinctly as they entered my system at the same time as the Playback Designs MTP-8 and MPD-8. And as per the manufacturer, the dac needs a good 500hrs to sound best.
I must be around 380hrs by now altogether, and the performance is great. Strong points are presence, layering, dynamics, high resolution and great 3d soundstage. Generally very rich, natural and musical. I think I read somewhere you were looking for feedback about the noise floor, well no worries there, it's dead quiet, I'm making no difference between the SIT5 and my Benchmark AHB2 which are world reference in that field.
For info, I'm coming from a pair of Gryphon Mephisto, and my preamp is the Esoteric C1, for the moment.
 
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Thanks for the reply Gary. I have the Volti Lucera’s with a sensitivity of 99db(probably more like 97db). My listening room is 23ft x 16ft. I just emailed Greg at Volti to determine the damping factor requirements of the Lucera’s.
I typically listen to music between 65-80db. But, when I’m in the adjoining kitchen, 3 season room or just listening to rock/metal loud, I’d like to keep the dynamics and bass control. Not sure if it’s the 8 watts or if it’s a 300b tube amp thing, but I’d like a bit more authority in the bass. The Volti’s are more efficient than the Audio Notes I had previously and some of my concerns have been alleviated. But, I am thinking of the future a bit. More power will allow a wider speaker choices down the line if I have to downsize from these behemoths! I’m not knowledgeable or experienced enough to know if the Sit-5 will be too much. Will more power give me the more powerful sound and oomph at the same volumes?
I will share what Greg tells me regarding the damping factor requirements. That may answer my question for me.
FYI and if it can help, my speakers are also 99dB, as Tannoy Westminster GR. My guess is that I will never go out of the classA envelope of the SIT-5. They look small and so ordinary next to my Gryphon, and yet they sound better in strictly every aspect, and they actually sound bigger too.
We have music playing for several hours in the morning and several hours in the evening, every day. For the last 2 weeks, they've been on almost 24/7. I think they've been off overnight twice so far.

There is a little grain for the first 3 or 4 days. By the first weekend things had started to refine in the treble, settle in. That is all in context though... probably in the first few hours after firing them up for the first time, I knew they were unlike anything I'd heard before.

It is also true, listening to them from cold, there is a notable difference in sound quality. They do need a good half hour warm up, but then there it is.

I'm 2 weeks in on the SIT-5 and I want for nothing. I think they are incredible.
Thanks
 
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Hello to all, my speakers are Tannoy Canterbury GR 96db, room is 47m2. I tryed many amplifiers and at the moment I have SIT4 on demo. I like the sound very very much. I have no chance for demo SIT 5. What do you think? To risk and order SIT 5 or just go for SIT 4.
Is the sound character very similar? Do I need more powerfull SIT 5 also for normal listening, I don't listen very loud.
Thank you for your help in advance.
 

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Hello to all, my speakers are Tannoy Canterbury GR 96db, room is 47m2. I tryed many amplifiers and at the moment I have SIT4 on demo. I like the sound very very much. I have no chance for demo SIT 5. What do you think? To risk and order SIT 5 or just go for SIT 4.
Is the sound character very similar? Do I need more powerfull SIT 5 also for normal listening, I don't listen very loud.
Thank you for your help in advance.
Hi Mostec
Here is my answer to your question that you asked back in May this year on the SIT 4 site.
My advice has not changed.

Hi Mostec
The First Watt SIT 4 produces 10 watts per channel into 8ohms.
My Cube Audio Nenuphar Mini speakers have an efficiency of 91 db compared to your Tannoy Canterbury GR speakers which are 96 db efficient.
My listening room is 45 m2 and the SIT 4 has no problem filling the room at a mid level volume setting on my Auralic Vega G2 analogue volume control. I do not think you will have any problems with power.

My Cube Audio Nenuphar's and the SIT 4 are a combination 'Made in Heaven' due to the very low damping factor of the SIT 4 (DF = 2) meshing well with the very powerful neodynium magnets of the Nenuphar's drivers. These drivers do not want an ampifier with a high damping factor as there is too much contol especially with the bass when paired with an amplifier with a high damping factor.
Not sure about the Tannoy's in terms of preferred Damping Factor.

I did find an intersting discussion on this very website, which you may have already read, but just in case . . . . . .

Which tube ampli for Tannoy Canterbury Se

Tannoy Prestige Gold Reference Canterbury Speakers Recommended amplifier power 20 - 300 Watts Continuous power handling 150 Watts RMS Peak power handling 600 watt Sensitivity 96 dB (2.83 volt @ 1 m) 17 more rows ... Feb 25 2021 Brand: Tannoy Nominal impedance 8 ohms...
www.whatsbestforum.com
www.whatsbestforum.com

The best advice that I read on this blog is to borrow the amp and listen for yourself. Great advice if you can organise a home demo or even in a store which sells both (good luck with that option !!).

I bought mine unheard after the glowing review on 6Moons and on HiFiKnight but in your (any & all) case, it is important for the speakers to work with the amp's characteristics.
As far as audio quality is concerned, if I could possibly summarise Srajan Ebaen (;)) this amplifier sounds like a "high definition" version of a 300B SET amp. I have to agree that that is a very accurate description.

I cannot help you with a recommendation with a suitable preamp as my preamp is built into my Auralic Vega G2.

Best regards,
Gary
 
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Hello to all, my speakers are Tannoy Canterbury GR 96db, room is 47m2. I tryed many amplifiers and at the moment I have SIT4 on demo. I like the sound very very much. I have no chance for demo SIT 5. What do you think? To risk and order SIT 5 or just go for SIT 4.
Is the sound character very similar? Do I need more powerfull SIT 5 also for normal listening, I don't listen very loud.
Thank you for your help in advance.
Hi Mostec,
I think that you ought to try the SIT5. I think that you will use the extra power at times, and at least there'll be enough when asked for. The Canterbury are efficient, but nonetheless, 15" need some power and control, and your room is quite large. You won't be taking great risks, as if you don't like them, which I doubt, you will easily resell. I would have suggested that you also try the XA25, it's different from all the other Pass models, and truly a reference amp. I'm personally going to use a pair in vertical biamping on various different speakers, as well as on Tannoy GRF90. But since you like the SIT4, the best move is to probably go straight to the SIT5.
 
This landed yesterday:
09b0d942-632d-49ef-9dd8-95cb08f2b277.jpeg

How hot do your SIT amps get? Mine was on for a few hours yesterday and it was very hot, could only touch the heat sinks for a few moments. The front plate was also hot.
 
Hi iaxel
both heat sinks and the front panel get very warm after 20 minutes or so. Not "fry-an-egg" hot but hot enough not to want to leave your hand there for to long. If I owned a thermal gun, I could give you an actual temperature reading. It is early Spring here in Sydney Australia and the typical indoor temparture is 20 to 22 deg C. Not sure how it going to go in the middle of Summer.
As this amp is pure class A, then you would have to expect that it is going to get very warm/hot.
 
Hi iaxel
both heat sinks and the front panel get very warm after 20 minutes or so. Not "fry-an-egg" hot but hot enough not to want to leave your hand there for to long. If I owned a thermal gun, I could give you an actual temperature reading. It is early Spring here in Sydney Australia and the typical indoor temparture is 20 to 22 deg C. Not sure how it going to go in the middle of Summer.
As this amp is pure class A, then you would have to expect that it is going to get very warm/hot.
Hi @Semiquavergarydesmondschu ,
Thank you!
The manual says touching the heat sinks for ~5 seconds should be fine, I feel that when it's very hot (after a few hours of operation), I cannot touch it for more than 2-3 seconds.
Not sure if this is an indication of a problem. The amp operates and sounds good - still burning-in (no pun intended).
If you can get a reading that would be great to rest my mind (or not).
 
Hi Mostec,
I think that you ought to try the SIT5. I think that you will use the extra power at times, and at least there'll be enough when asked for. The Canterbury are efficient, but nonetheless, 15" need some power and control, and your room is quite large. You won't be taking great risks, as if you don't like them, which I doubt, you will easily resell. I would have suggested that you also try the XA25, it's different from all the other Pass models, and truly a reference amp. I'm personally going to use a pair in vertical biamping on various different speakers, as well as on Tannoy GRF90. But since you like the SIT4, the best move is to probably go straight to the SIT5.
Mr. Hubert thank you for your reply. I just ordered SIT 5. Have a good day
 
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This landed yesterday:
View attachment 157640

How hot do your SIT amps get? Mine was on for a few hours yesterday and it was very hot, could only touch the heat sinks for a few moments. The front plate was also hot.
Nice!
I have the SIT5, and they can get very hot, depending on the day's temperature and aeration it gets. But it's also 40W classA. But then again you're sit4 is only one chassis.
Mr. Hubert thank you for your reply. I just ordered SIT 5. Have a good day
Congrats Mostec!
By the way, I'm Hubs, admin from the Facebook Tannoy group.
 
I just wanted to follow up. I was dropping off all my gear at the dealer who purchased it and decided to have a listen to some gear. Listened to several Audio Note amps, Soro Sig and some others and some Western Electric amps, which I didn’t know prior to listening. In each room I listened, the WE’s sounded awesome. I couldn’t resist and walked out with a WE 124, 6l6, with vintage parts and a Lector s192 tube dac. The Rockna dac I sold was more detailed and had much more leading edge, attack I think. Found it a bit too revealing and was listening to the recording as opposed to the music. New system is smooth and very musical. More relaxing on the brain and ears. Has way more oomph now as well. So tubes for a bit longer!
 
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Just received SIT 5. I have two preamps one is EAR 864 and Benchmark LA4. SIT 5 is stunning amp, sound is live, transparent and what I was surprised even at low volume (late night listening) room 47m2 is foul of sound. Nelson Pass is a genius!
 

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SIT-5 OPERATING TEMPERATURES

Hey guys,

I just got my SIT-5s and set them up to burn in for a few days before listening. After 48 hours I took a video of the steady state temperatures, as the operating temperatures of these seems to be something people ask about or remark upon.

Here are the screenshots. Looks like the tops get to be about 111 degrees and the cooing fins to about 128 degrees. Not really that hot to the touch.

Like they say, give them space to breathe.
 

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SIT amps run hot. I just ran my SIT 4 with signal for 300hrs to fully break it and my new EM/IA Elmaformer Ag in completely. It reached a pretty warm temp and stayed there. It never got too hot to not be able to lay my hand on it.

The EM/IA Elmaformer with the SIT4 is a match made in Heaven. Very transparent and refined. As good as I’ve ever heard. I assume it would work equally well with the SIT 5 even with the different topology. The SIT 3 was common drain like the SIT 5. It sounded great with a passive pre but didn’t have enough gain so spl was very limited.
 
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TIME TO TEMPERATURE

I got the SIT-5s set up last night. After power up, 30 minutes in they are just starting to get warm. 90 minutes much better.

Two hours though to get totally up to steady state temperature in my hands. I will turn them on when I get home from work but weekends just leave them on the whole time.
 
Guys,

So a this point I have now racked up a bit more than just a few hours listening to the SIT-5s in my system, after burning them in for 72 hours.

I am streaming Qobuz into a dCs LINA, with the LINA clock and a good set of clock cables, (which is another topic) then into a Pass XP-32 to biamped Rockport Orions, that after 9 months are finally broken in. The SIT-5 is thus only responsible for the 7" woofer and 1.25" tweeter, with the lower corssover at 120 hz. So it runs everything above that, and thank you Andy Payor for the low cross over point. I really, really love the Orions at this point.

Below 120 hz, the 13" woofers are driven by Pass X260.8s, which are sized perfectly for them, controlling them perfectly, complementing the Perlisten D12 subs on the very bottom. The XP-32 allows for adjusting the gain between the amps, as the X260.8 is 26dB, and the SIT-5 is 19 dB. Prior to this I was using dual XA25s per channel for the highs, which are like 20dB gain which worked great.

With the XP-32 you just dial back the Slave 6 or 7 db, which makes the outputs matched. I touched it up with REW, which works great.

In terms of listening, there aren't enough adjectives and superlatives to describe the phenomenal sound quality of the SIT-5 and it's attributes. You can run through the standard reviewers lexicon and check all the boxes, but it's even beyond that. I have never heard anything like it.

I would say the sound is incredibly liquid with fluid defined highs, extremely dynamic without constraint, with a full resounding upper bass especially apparant on acoustic guitar for some reason. I don't know why, but I heard guitar notes and chords in songs that I have listened to for 20 years, that I never heard before. They pop out at you from their position in space, and everything is there in space like small points of dense sound tightly focused. For the first time the bass lines in George Michael's "Cowboys and Angels' was set out clearly and uncongested, for example. The guitar on the Getz/Gilberto 'Girl for Ipanema' sat there mid left clearly like he was in a chair in front of me brushing the strings with his fingers. Astrud pops out on the left like she's standing there.

The other aspect of the sound was the density and harmonics of the piano. Ricki Lee Jones, 'For No One' for example, and more. All the Diana Krall standards, which I shall not enumerate.

Particularly, as noted, the harmonics of all the instruments resonated endlessly. I have never heard anything like this.

Power-wise, it drives relentlessly, somehow playing louder than indicated on the gain, where I dialed it down even compared to the XA25s, which are very dynamic on their own and quite transparant. The SIT-5 also drove the upper end of the Orions effortlessly to high sound levels without strain. I went no further but saw 105 db peaks 14 feet from the front of the speakers in my 10,000 ft3 room. It felt like endless power. I don't know what the relationship is between tested steady state continuous output and dynamic power, but music requires high dynamic power and these amps have that in spades.

I could go on and on, but I am not some professional reviewer, so I will spare you guys anymore of this blather. I have reached my own personal nirvana here, and I am done for a long great while except for maybe finally fiddling a bit more with cables in a year or so. I am sitting here this weekend for hours listening to all my favorites again and again, hearing what I have never heard, while I enjoy a nice 2016 Super Tuscan. I think when that happens you know you system has take a big step up. You just go wow.

Well Done, Nelson Pass. I think the SIT-5 is your Magnum Opus, and considering what you have done before that is truly a great thing. I just can't imagine this effort will be easily surpassed by anybody, although there are lots of more powerful amps.

Thank you very much, Nelson.
 

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