Stello ai500 Integrated amplifier?

Read some great reviews of this unit?
Anyone own or tried this unit? If so, what associated equipment and appreciate your listening experience.

I was expecting a few responses regarding this topic but I trust most have not been exposed too much with this product line just as me. First impressions are so very ambiguous since we never capture an intimate state unless once becomes accustom to the subject in place.

I saw the Ai500 amplifier along with some of the other lines at the 2010 CES and never actually paid much attention to it since they could easily be mistake as one of the “Nagra” type Swiss product line and I was pretty much content keeping my distance based on what I have read and understood about such avant-garde designs.

That being told, I was not fussy about the appearance of the Ai500 as well (including some Nagras) and then found out that this product that was made in the Far East. I have sadly become complacent with such products compared to what I have been blessed with and accustomed to with such systems such as ARC, Wilson, Sonus Faber, McIntosh to name a few.

This year I came across this piece once again and decided to do some research and found something a little different about it. I have owned almost 30 state of the art Integrated amplifiers in my life with tons of highly regarded pieces and those accounted for great value for the money, like the Rowland Concentra, Dar Tzeel 8550 (?), Krell 400xi, BAT, Levinson, VAC, ARC, Jadis….. please do refer to my earlier predated posting on Best Integrated Amplifiers for details at Audiogon if you are interested.

For the money I believe the Krell 400xi with Cardas Golden Reference cables attached (which will amount to cost of the amplifier itself) has been one of the best combos I have had as a tertiary system of mine and for an amplifier that was under $2500 thanks to the respectable Dan D’Agostino, it was always an experience when the system was fired up and it does get me excited when a new cd is added onto the inventory.

Today I have actually found an integrated amplifier that could easily be on par with my faithful Krell 400xi or even better it is certain areas primarily when it comes to neutrality since it reminds me of my Ayre Pre Power combo. It also has a tremendous reserve for current capability, yes managing my Magnepan 3.6R well.

This “newly encountered” (its been out several years) rock solid 35 pounder, built in DAC (which I am not using so I will not share my opinion on that) the oversized 800VA toroidal transformer and 90,000mF of caps, delivering 150Wpc into 8 ohms or 300Wpc into 4 ohms, class-A/B output stage uses matched Hitachi MOSFET power transistors in a push-pull configuration, Cirrus Logic microprocessor volume control and the remote which can pretty much be used as an optional club or weapon for self defense. These are just some of the offerings this company from Korea has for us. I can’t believe I am actually saying this but this is just a good product coming from Korea.

I am enjoying this unit immensely and I strongly urge anyone out there who is looking for an integrated amplifier to give this a try if you have $3500. The only issue I have had with the unit is that you should never audition this unit in its first half hour of operation, it needs to run before it performs and once you get a good warm feel on the top of the air intakes…..its a blast! I was impressed to a point that I have decided to order their top of the line DAC/ headphone amplifier, the Eximus DP1 to see what that is all about. Now this thing looks pretty darn good, thanks to the enclosure that was meticulously designed by Alex Rasmussen.

Rapogee, thanks for taking the time to write this. It has provided some very good insight into the Stello as well as the Krell integrated.

I'm looking to upgrade my current system from the NAD 325BEE I'm using. This info has been very helpful. Thanks again.


You are most welcome Scott,

I am happy to be able to provide some insight based on my experience.
Once being fairly selfish on such finding of hidden treats in the quest for sound, and being involved in this racket for well over two decades brought me to a realization that the more, the merrier it is to share. I do enjoy sharing and learning from others now.

The NAD you have is such a great little piece of achievement by this long running company, not forgetting their newer upper M3 series as well which is a real delight.
It’s really exciting when you find such equipment that is a fraction of the cost but delivers a substantial portion of the very best out there.
The Krell 400xi Integrated was a breakthrough in design in my opinion, massive Toroid, surface mount direct coupled and no caps….its a true feast and I will continue to say “Dan is the Man”, the master of amplifier designs. That “little” integrated, 30lb with lightning speed and current, transparency and resolution and not forgetting the bottom end was just mind boggling for $2500, a true Krell signature right there. The looks is truly a bonus compared to what that amp is capable of doing.

When I first heard it, it was sad since I used to enjoy my Creek 4330mk2 in the early days until the Krell was placed into the chain and it was just annihilated it in every way (not a fair test obviously with the price ratio). It just had Gobs and gobs of power, control and detail that I was not accustomed to from the little Creek.
I had never ever heard monitors sound so big and full until I was introduced to the Krell, it was driving a pair of Sonus Faber Electa’s. Good memories most certainly. It never ever sounded like my bigger Krells such as the FPB600c or the Monos but it had that signature Krell sound assured with a good portion of its performance is a much lighter package. That is true engineering!

The Stello ai500 reminds me of the Krell 400xi but with much greater Neutrality which I think would entice many new listeners who are seeking for that missing edge that some amplifiers fail to deliver.

Good luck
I was just at the Seoul Audio Show and heard the new Eximus preamp and amp running a pair of Wilson Sashas and I was very, very impressed, as I've always been from Simon Lee's units. April Music is fantastic company and I'm happy for you for your purchases.
I have owned the Ai500 about 8 months. It is a great integrated (even if you exclude the dac).
It is definitely well built. As Rapogee states, you do need it to warm up a bit. After running it for awhile, the unit does get get warm (around Bryston warm but not hot that you can fry an egg or burn yourself).

The amp has great control & authority and can handle my PMB MB1 by itself. Of course it has drawbacks when your try to power something this large but it has worked better than I have expected. It can control the woofers with ease and does provide some lushness for vocals with great neutrality. Maybe a tad bit of resolution loss b/c of the dirvers sucking the power out when playing 1812 but nevertheless still amazing!

Did I mention the fact that you can use it to bi-amp? I used the Ai500 to drive the 12" on the MB1 and Vitus for the tweet/mid. It was glorious!

I eventually (and regretably to this day) sold it as I did not have an extra setup for 2 systems so it would have been collecting dust in the corner of my room. I do miss it and I would not hesitate to buy it back if I need another amp. The guy who bought it from me has been VERY hapy with it driving his custom built ribbons and 2x8" Nuform Research bass drivers.
Hope I'm not to late for this blog but how would the Stello stand up next to a good tube amp?