ATI AT525NC Teardown

[RichB]

I purchased an ATI AT525NC 5x200 WPC NCore amplifier for a family vacation home to replace the 20+ year old Sunfire Cinema amp (also 200 WPC).
This amp will be connected to a Denon 3700H receiver (in preamp mode) to drive Revel M20's and a C20 center channel.

I chose it because it it would run cool when placed in a cabinet in a non-airconditioned home.
I have auditioned the 2-channel version with the M20's and sent that for review here:

https://www.audiosciencereview.com/forum/index.php?threads/ati-at522nc-stereo-amplifier-review.9999/

These amps use smaller transformers than their class A/B counterparts (AT4000 series) but this is not a lightweight amplifier. I estimate about 50 lbs.

- Rich

 

[boXem]

Thank you!
Interesting to see that the Hypex modules have ATI marking on them.

 

[Deleted member 65]

Interesting to see the substantial cooling implemented, never seen that on nCore’s before.

 

[Phorize]

Great Scott, do I see a U.K manufacturered transformer?

 

[Phorize]

With a 7 year transferable warranty, that’s excellent.

 

[boXem]

Interesting to see the substantial cooling implemented, never seen that on nCore’s before.

On NAD M27, with better airflow if I remember well.
You also have to take into account that these are multichannel amps.

 

[peanuts]

wonder what their reasoning is for not using smps

 

[RichB]

wonder what their reasoning is for not using smps

They have more experience with transformer designs. I wish they did.

- Rich

 

[dfuller]

wonder what their reasoning is for not using smps

Could be a number of things; linear PSUs can have much more current reserve through the use of effing big reservoir caps so they can deal with much higher transient spikes without significant voltage sag. SMPS is better in basically every other way than that. Back in the day linear designs were much lower noise than SMPS (which used switching frequencies in or near the audible spectrum) too.

The other major thing is people associate weight with quality so there's something there.

 

[Ilkless]

Interesting that they are using Noratels. One of the things ATI is very proud of is their in-house toroid winding capability - they wind their own custom toroids for their class AB designs, so it's surprising to find it supplied from an OEM here. Than again, it would make sense to keep that in-house capability/vertically-integrated capacity for the class AB stuff that's the bedrock of the brand.

 

[bigLP]

Could be a number of things; linear PSUs can have much more current reserve through the use of effing big reservoir caps so they can deal with much higher transient spikes without significant voltage sag. SMPS is better in basically every other way than that. Back in the day linear designs were much lower noise than SMPS (which used switching frequencies in or near the audible spectrum) too.

The other major thing is people associate weight with quality so there's something there.

I called ATI before buying a 542nc. As I can recall and understand they pretty much said they know linear not smps and they like how linear supplies current(as stated above). I did a sighted comparison between my 542nc and the 4000 Signature my dealer had.
I bought the ncore amp because of size, its much smaller than the 4000sig. Sound wise I discerned little difference. Perceived plus and minus for both. Dealer loved the 4000 btw. There was also an NAD amp there, not sure which of the new ncores it was(This was 12 months ago or so). Little difference recognized there too. Cant say why, but I liked the ATI sound better. I assume it's because I know they are made in America
This kind of makes me want to take top off mine. I assume it would be the same, except doubled up modules?

 

[Ilkless]

I called ATI before buying a 542nc. As I can recall and understand they pretty much said they know linear not smps and they like how linear supplies current(as stated above). I did a sighted comparison between my 542nc and the 4000 Signature my dealer had.
I bought the ncore amp because of size, its much smaller than the 4000sig. Sound wise I discerned little difference. Perceived plus and minus for both. Dealer loved the 4000 btw. There was also an NAD amp there, not sure which of the new ncores it was(This was 12 months ago or so). Little difference recognized there too. Cant say why, but I liked the ATI sound better. I assume it's because I know they are made in America
This kind of makes me want to take top off mine. I assume it would be the same, except doubled up modules?

Fair game to that. Playing to their expertise and experience, as well as differentiating their product. I really respect ATI for that warranty and clear commitment towards a reliable, long-lasting and understressed product.

 

[MakeMineVinyl]

wonder what their reasoning is for not using smps

Linear supplies are able to store more instantaneous current capability for heavy transients. Finding a smps which has the overall ability to supply enough current for up to 8 channels is also an issue. Using multiple smps helps, but these actually take up more real estate inside a chassis than a linear supply. Note also that this amp has auto-ranging AC supply sensing so it can be plugged into either 120V or 240V and the linear supply will switch accordingly. The NC500 modules have a range of supply voltages, and with the linear supply, the rails can be toward the higher end of this range and the microcontroller will keep things safe if the AC mains gets too high/low. A smps is not usually voltage adjustable on its output. Higher output wattages are thus realized in comparison to the same modules with a smps. The relatively larger heatsinks on the ATI amp modules help facilitate this higher wattage.

 

[Jim85IROC]

I called ATI before buying a 542nc. As I can recall and understand they pretty much said they know linear not smps and they like how linear supplies current(as stated above). I did a sighted comparison between my 542nc and the 4000 Signature my dealer had.
I bought the ncore amp because of size, its much smaller than the 4000sig. Sound wise I discerned little difference. Perceived plus and minus for both. Dealer loved the 4000 btw. There was also an NAD amp there, not sure which of the new ncores it was(This was 12 months ago or so). Little difference recognized there too. Cant say why, but I liked the ATI sound better. I assume it's because I know they are made in America
This kind of makes me want to take top off mine. I assume it would be the same, except doubled up modules?

it might be because I'm old fashioned, but I prefer linear power supplies. To me, the ability to deliver those large volume spikes is much more useful than moving an already inaudible noise floor even lower.

 

[Head_Unit]

Interesting to see the substantial cooling implemented, never seen that on nCore’s before.

Once upon a time, a fellow I knew went to Infinity and made the first Class D automotive amp. It was very compact for shock and awe...but thus didn't have enough heatsinking, since Class D is not 100% efficient...and thus they took a LOT of returns. So even the efficient amps need cooling.

As for the linear supply, yeah RFI and expertise. For non-pro applications I think few users care about really low weight (though I loved the QSC PowerLight I would use for testing, I coulda balanced that on my nose like a seal )

I guess the ATI tours are not running due to COVID; we hope to visit somebody this coming Saturday who has one.

 

[blueone]

it might be because I'm old fashioned, but I prefer linear power supplies. To me, the ability to deliver those large volume spikes is much more useful than moving an already inaudible noise floor even lower.

I thought the higher peak voltage from larger smoothing capacitors notion in linear power supplies was a myth. Here's the best explanation I've read. See section 5.3 on the link below.

https://sound-au.com/power-supplies.htm

 

[Diamata]

Interesting that they are using Noratels. One of the things ATI is very proud of is their in-house toroid winding capability - they wind their own custom toroids for their class AB designs, so it's surprising to find it supplied from an OEM here. Than again, it would make sense to keep that in-house capability/vertically-integrated capacity for the class AB stuff that's the bedrock of the brand.

ATI have been using Noratel transformers for theirs and other class AB designs for Lexicon, Monoprice etc since 2007 or probably before then.