Looking for thoughts on ATI amps

[mazersteven]

So which do you purchase?

Amplifier Technologies Inc.

At ATI, we make heavy-duty amplifiers with proven circuitry, meticulous assembly and rigorous testing designed to deliver state-of-the-art audio for years, all designed by us and built in our own US factory. It’s a simple story, American amplifiers built by American people. We hope you enjoy...

www.ati-amp.com

Monolith by Monoprice 7x200 Watts Per Channel Multi-Channel Home Theater Power Amplifier with XLR Inputs - Monoprice.com

The Monolith™ 7X is a state‑of‑the‑art, high‑performance, audiophile‑grade multichannel home theater amplifier. Rated at a full 200 watts per

www.monoprice.com

 

[Irvrobinson]

Oh then I missed that part, you are right Outlaw claimed fully balanced for the 7900. By the way, don't you find ATI (and by association, Outlaw too quite often) just don't seem to be clear about their input sensitivity/gain specs?

We both can calculate output from input voltage and gain:
For 1.6 volts input, and 28 dB gain, output from the XLRs will be about 202 W, not 250 W.
For 1.6 volts input, and 34 dB gain, output from the RCAs should be about 803 W, not 250 W either.

Now look at the table below, that I pasted from the manual, you can reconcile the gains for RCA, XLR input, the input sensitivity, and the rated output power at 8 ohms. Well one exception, it would work for the AT2000's 200 watts, based on 28 dB gain and 1.6 volts XLR input. It wouldn't work if the 1.6 volts is for the RCA input. Nothing works for the AT3000's 300 watts, input sensitivity 1.8 volts no matter how you cut it. I have never seen this kind of confusion on these same specs for any other power amps, only ATI's, and some Outlaws. Monolith's seems fine, now that I know about the new "normalized input voltage" feature.

View attachment 39786

I never noticed the input sensitivity anomalies. You're more detail-oriented than I am.

 

[Irvrobinson]

ATI amps have excellent reputations – they are said to be first rate. They are one of the few amplifier manufacturers in the US.

Understand that ATI does manufacture amps for other companies under contract. For example, ATI builds amps for Monolith and Outlaw, built to their specifications, not ATI's. I once read that ATI can fabricate it's own steel chassis and wind their own transformers in their factory. So they can include those expensive parts in their contract builds instead of requiring that they be outsourced.

ATI now owns the B&K and Theta amp designs and company names. Those companies had gone out of business. It that true for Levinson as well?

ATI definitely uses their own designs as the basis for their contract amps. I suspect most of the differences are to meet price points, like for Outlaw and Monolith. The Mark Levinson and Lexicon designs look just like ATI designs with different case work.

The Mark Levinson brand is still active in Harman/Samsung, though I think the latest technologies have left them behind. I suspect most of their volume goes to Asia, where the brand is still revered for high-end build quality. They are assembled in the US by Mack Technologies. And of course, there's the ML audio systems in Lexus vehicles.

 

[70sMac]

Agreed. I just got done looking (drooling) over it. Lots of power, and those pretty blue dials... I love the way Mac gear looks.

I think that @PENG may have been complimenting the Outlaw Model 7900 I mentioned, but we appreciate the compliment, regardless. We've used the amp for many years now and it is deadly quiet. We have zero complaints.

 

[PENG]

I think that @PENG may have been complimenting the Outlaw Model 7900 I mentioned, but we appreciate the compliment, regardless. We've used the amp for many years now and it is deadly quiet. We have zero complaints.

You are correct, but there is no need for me to say anything about the MC300, we all know it is a great amp to have. Probably won't measure better than the more modern amps at half it price but it should still sound transparent to people with normal hearing.

 

[PENG]

I never noticed the input sensitivity anomalies. You're more detail-oriented than I am.

May be, and probably just me.. I won't buy amps from ATI because of their apparent sloppiness in specs. I did buy and still own the Parasound Halo A21 but for the same reason I won't buy another Parasound amps either until I see changes. It is a shame that even higher priced products don't seem to do much better, though better. McIntosh, Bryston's look much more acceptable, Krell's are probably as good as they get, better by perhaps only the likes of the late comers such as Hypex, Purifi class D amps.

Outlaw and Monolith's are acceptable to me only because they are not totally responsible and are priced in the lower range bracket. ATI, supposedly pride themselves in being one of the best in making power amps. The way they spec'ed their products doesn't give me the confidence that they have too many real electrical/electronic engineers on their technical teams (I am sure they do, but may be not given enough say..).

Just venting, not ranting..

 

[Irvrobinson]

Outlaw and Monolith's are acceptable to me only because they are not totally responsible and are priced in the lower range bracket. ATI, supposedly pride themselves in being one of the best in making power amps. The way they spec'ed their products doesn't give me the confidence that they have too many real electrical/electronic engineers on their technical teams (I am sure they do, but may be not given enough say..).

Just venting, not ranting..

My guess is that the engineers don't write the spec sheets or any of the advertising copy. ATI is not the only transgressor. A while back the Revel web site reversed the labelling on the tweeter and upper bass drivers for the Salon2 speakers. I didn't take that as an indicator of their engineers' skills.

To be honest, ATI has come down a notch or two in my mind. First they put that horrendous Kessler signature on their 4000 and 6000 front plates, and then they stuck a linear power supply in their Class D amps, making them nearly as heavy as their old Class AB offerings. I'll almost certainly keep my ATI AT3005 until it breaks outside of the warranty coverage, but after that either the Benchmark ABH2 or the newest Class D monoblocks with switching power supplies are looking attractive.

 

[PENG]

but after that either the Benchmark ABH2 or the newest Class D monoblocks with switching power supplies are looking attractive.

Funny that's my plan, well may be just "goal" too. I believe the best sounding amp is one that has the lowest distortions of any kind and the highest SNR, DR, slew rate etc., because if I want to spice things up I can do it myself.

It is not difficult for me to understand people who believe even well designed amps have their own sound signatures, but it is near impossible to understand why a) that different signature would be audible given human's limited bandwidth and ability to notice even 0.05% THD of any kinds in various studies, b) such alleged signatures were there by design, and c) that somehow they can choose the one with the signature they like better doing their own AB sessions of many different amps, and d) that such signature would somehow stick with the brand.

For me, it is so simple, if 50 W is all I need based on 20-25 dB dynamic peaks for what I listen to, then the AHB2 is the best amp I can afford. If I want to have an extra 6 dB of headroom that I don't actually need, then I would just buy a Purifi amp, for about the same money. No need to have to worry about how to find time and to convince various dealers to let me do the necessary AB comparison listening with at least half a dozen of amps of my choice otherwise.

 

[70sMac]

For me, it's even simpler. The Mrs has become quite the Mac fan over the years, so the Mac brand is always at the top of the list. I'm giving the other power amp brands a good look to see if other so-called "US brands" have developed a strong reputation over the years -- and durability is the key for me, personally. It wouldn't hurt, either, if the other US brands have a strong following. So far, ATI power amps have been recommended to us the most as an alternative to Mac -- even by other Mac owners.

 

[AcuDefTechGuy]

For me, it's even simpler. The Mrs has become quite the Mac fan over the years, so the Mac brand is always at the top of the list. I'm giving the other power amp brands a good look to see if other so-called "US brands" have developed a strong reputation over the years -- and durability is the key for me, personally. It wouldn't hurt, either, if the other US brands have a strong following. So far, ATI power amps have been recommended to us the most as an alternative to Mac -- even by other Mac owners.

Amps are a lot simpler than Pre-pros for sure.

People can nit-pick about this and that. At the end of the day, what I care about are these.

1. Cost. Personally I don't like spending too much. Other people are a lot more willing to spend. ATI amps are usually more expensive than some other amps.
2. Reliability history. ATI has a long history of being one of the most reliable amps.
3. Power output. ATI amps have the reputation of being "Arc Welders". They are considered hardcore amps that can output a lot of power. Both @Irvrobinson and I have used our ATI 60 Watts per Channel amps to power our Revel Salon2 towers. If buying external amps, instead of AVRs, I'm not buying any 100WPC amps - I'm buying 200WPC amps or close to it. Otherwise, just stick to AVRs.
4. Great Specs - All the ATI amps have great specs. SNR is usually 120dB+, Crosstalk is usually 100dB, etc.
5. Reputation. ATI has the reputation of building amps for many companies as you've heard - Mark Levinson, Lexicon, Cary Audio, Outlaw, Monoprice, and some others that we can't prove since ATI isn't allowed to disclose the brands. ATI also owns ultra-high-end Theta Digital ($20K pre-pros), DataSAT ($20K pre-pros).

McIntosh makes good amps. But there are people who also disagree with some of their technology/philosophy as well. I'll lump this in with the nit-picking. At the end of the day, McIntosh makes good amps and so does ATI, regardless of the nit-picking.

If your wife wants McIntosh amps, I wouldn't disagree with her wishes.

 

[PENG]

So far, ATI power amps have been recommended to us the most as an alternative to Mac -- even by other Mac owners.

Count me as one who do recommend ATI amps too, I won't buy one but not for any valid reason, just bias.

 

[70sMac]

Although I have an electrical background, when it comes to the sonic range, I leave it to the audiophiles. This group seems to have a lexicon all their own, and I'm a bit too old to be trying to learn a new language.

That being said, the matter, again, becomes quite simple. Is their another US power amp brand that has developed a great reputation for durability? As I said in the last post, the ATI brand name keeps coming up as an alternative to Mac power amps, which I see as a very encouraging sign.

As for the nit-picking...all I know is that we have Mac equipment that hasn't failed to operate since the late-70s. It has also sounded great -- to our ears -- over the decades, so, once again, we would have to find another reliable US brand before we mix another amp in with our glass front stuff. At this point, I will continue looking into ATI. Thank you for the post.

 

[mazersteven]

Is their another US power amp brand that has developed a great reputation for durability?

Not a US company, but has a great reputation for Quality

Bryston

Amplifiers – Bryston

bryston.com

 

[70sMac]

Not a US company, but has a great reputation for Quality

Bryston

Amplifiers – Bryston

bryston.com

Yes, great point. I've actually spoken to a tech rep at Bryston: and it went very well. The only problem there, however, is that finding a decent multichannel (MC) Bryston power amp, on the used market, is very tough.

 

[Irvrobinson]

Amps are a lot simpler than Pre-pros for sure.

People can nit-pick about this and that. At the end of the day, what I care about are these.

1. Cost. Personally I don't like spending too much. Other people are a lot more willing to spend. ATI amps are usually more expensive than some other amps.
2. Reliability history. ATI has a long history of being one of the most reliable amps.
3. Power output. ATI amps have the reputation of being "Arc Welders". They are considered hardcore amps that can output a lot of power. Both @Irvrobinson and I have used our ATI 60 Watts per Channel amps to power our Revel Salon2 towers. If buying external amps, instead of AVRs, I'm not buying any 100WPC amps - I'm buying 200WPC amps or close to it. Otherwise, just stick to AVRs.
4. Great Specs - All the ATI amps have great specs. SNR is usually 120dB+, Crosstalk is usually 100dB, etc.
5. Reputation. ATI has the reputation of building amps for many companies as you've heard - Mark Levinson, Lexicon, Cary Audio, Outlaw, Monoprice, and some others that we can't prove since ATI isn't allowed to disclose the brands. ATI also owns ultra-high-end Theta Digital ($20K pre-pros), DataSAT ($20K pre-pros).

McIntosh makes good amps. But there are people who also disagree with some of their technology/philosophy as well. I'll lump this in with the nit-picking. At the end of the day, McIntosh makes good amps and so does ATI, regardless of the nit-picking.

If your wife wants McIntosh amps, I wouldn't disagree with her wishes.

To be completely open about it, I tested the AT602 amp with the Salon2s, but I didn't ever use it long-term. I thought the combination sounded great in the tests, but I seemed to get the AT602 to clip on some bass-heavy music. I say "seemed" because there's no visual indication, but the AT602 has soft-clipping circuitry, and it seemed pretty audible when it happened compared to hooking back up the more powerful amps.

My AT3005 wasn't impressively reliable, since one channel went out due a few blown capacitors. However, ATI customer service was great (though the tech I talked to was a bit condescending), and they allowed me to disassemble the amp and ship only the blown channel module. Good thing, because the full assembled unit weighs over 100lbs net.

 

[Irvrobinson]

I didn't think the 6000 series was introduced until about 2014. The Outlaw was introduced in what, 2011? Before? Also, Outlaw advertises the 7900 as "fully balanced", which is the AT3000-series topology; the AT3000 are balanced bridged designs (the AT2000s too). With the 6000 series ATI went to a single-ended input stage, claiming it improved SNR. I have no idea which is really better.

I need to correct this post. The 4000/6000 series input stage is not single-ended. The design uses a single balanced input stage per channel, but the output stage for each channel is still dual-differential. Sorry if my mis-typing caused confusion.

 

[M Code]

Regarding ATi amplifiers, note they build for many OE brands. But now due to certain cost factors, they are sourcing toroidal transformers and amplifier modules from off-shore with final unit assembly in the USA.
But..
IMHO..
They are still a good choice for value, performance and reliability...

Just my $0.02...

 

[Irvrobinson]

Regarding ATi amplifiers, note they build for many OE brands. But now due to certain cost factors, they are sourcing toroidal transformers and amplifier modules from off-shore with final unit assembly in the USA.
But..
IMHO..
They are still a good choice for value, performance and reliability...

Just my $0.02...

ATI goes down another notch on my ledger.

 

[Out-Of-Phase]

Regarding ATi amplifiers, note they build for many OE brands. But now due to certain cost factors, they are sourcing toroidal transformers and amplifier modules from off-shore with final unit assembly in the USA.
But..
IMHO..
They are still a good choice for value, performance and reliability...

Just my $0.02...

Interesting. I was under the impression that their toroidal transformers were designed and manufactured in-house in California.

 

[mazersteven]

O No all the ATI fan boys are going to be UpSet