Visit to audioquattr in The Netherlands / Alieno 250 OTL

Ron Resnick

Site Co-Owner, Administrator
Jan 25, 2015
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#1
While we were in The Netherlands I took three trains to visit Jeroen, WBF member audioquattr, in the town of Lochem, about two hours Northeast of Amsterdam.

While my Dutch wife had never heard of Lochem, it turns out that Lochem is a very pretty small town with a genuine small town vibe and very cute restaurants, bars and stores.



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The town hosted a music festival tonight!

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Jeroen is only about a twenty minute drive away from WBF member Audiocrack. I will be introducing them to each other in due course.

Jeroen's house is a very large and beautiful 300 year old stone house with fortress-like walls. He and his wife completely renovated the house a couple of years ago.
 

Ron Resnick

Site Co-Owner, Administrator
Jan 25, 2015
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Beverly Hills, CA
#2
Jeroen's system consists of Magico M3 loudspeakers, the top-of-the-line Pass Labs Xs phono stage, and a Dr. Feickert Blackbird with an Ikeda IT-407 tonearm which carries a Shelter Harmony cartridge. The line stage is the Dan D'Agostino Momentum preamplifier. The amplifier is the very intriguing Alieno LTD 250 OTL amplifier.

Everything is powered by a PS Audio P10, including the amplifiers. Interestingly, Jeroen reports that the system sounds better when he is able to control the AC voltage and keep that setting stable.

Jeroen's dedicated listening room is about 17 feet wide and about 27 feet long with a very tall ceiling. He has spent a lot of time experimenting with different absorbers and diffusers and fine-tuning the acoustics of the room. I saw SMT diffusers in several locations.



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Jeroen graciously played some very interesting modern jazz I had not heard before; "Dreams" by Fleetwood Mac on Rumours; Bill Evans; Ry Cooder; Supertramp; and "Bird on a Wire," "Joan of Arc" and "Song of Bernadette" by Jennifer Warnes on Famous Blue Raincoat.
 

Ron Resnick

Site Co-Owner, Administrator
Jan 25, 2015
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#3
The Alieno is a two chassis stereo amplifier with a power supply, which looks like a full-size conventional Class A solid-state stereo amplifier, on the bottom, and a pair of small input tubes, a pair of KT-150 driver tubes and a pair of 300B output tubes recessed in an acrylic box on the top. The power supply on the bottom is connected by three umbilical cords to the tube circuits on the top: there is what looks like a left channel cable, a right channel cable and a power supply cable.



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Jeroen showed me the manual for the Alieno and the description exclaims at least twice that whatever you think of this circuit design it is not a hybrid and there is no solid-state amplification going on. There is no output transformer and no output capacitors to couple the amplifier to the loudspeakers. Alieno terms this OTL/OCL.

So how is a single KT-150 driving a single 300B producing 250 watts per channel? Maybe the tubes are amplifying voltage, and devices in the power supply are amplifying current? But the manual expressly disclaims that this is what is going on. So what is going on?

I don't know what's going on, but I know I like it. The Alieno drove the 91dB M3s to SPL of 100dB or more without breaking any sweat at all. (It was convenient that Jeroen and I like the same fairly loud listening level.)

As much as I love the crystalline transparency of Atma-Sphere amplifiers and of the Einstein OTL I hear a lean-ness in those amplifiers to which I am not accustomed from various transformer-coupled tube amplifiers. The warmth and body to which I am accustomed from output transformer-coupled amps may, in fact, be a colouration artifact of transformer output stages. And I'm quite sure the transformer adds a slight layer of haze, the absence of which gives the OTL amplifiers this crystalline clarity and transparency that I love.

Somehow this Alieno manifests most or all of the crystalline transparency and little or none of the transformer haze -- without sounding lean. We have to understand the circuit design of this Alieno amplifier. I have researched it on the Internet and I find very little about Alieno Ltd. -- and nothing in English.

I enjoyed very much the sound of Jeroen's system! I heard crystalline transparency and enormous jump factor and lifelike dynamics. All of the time Jeroen has spent on acoustic treatment results in great width and depth of soundstage. With Magico speakers and solid-state preamplification I was not surprised to hear incredible detail. I heard the best and most detailed rendition of Dreams I have ever heard!

Thanks very much to Jeroen for a great day and evening and a wonderful listening session, and for introducing me to a new top amplifier contender!
 

Tango

VIP/Donor
Mar 12, 2017
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Bangkok
#4
I hope you get a chance to visit Audiocrack. His system is very interesting. But maybe he is still in the process of breaking in and optimizing his Kagura, so might not be a his top form :cool:

Tang
 

Ron Resnick

Site Co-Owner, Administrator
Jan 25, 2015
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Beverly Hills, CA
#5
May 30, 2010
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Portugal
#6
(...) So how is a single KT-150 driving a single 300B producing 250 watts per channel? Maybe the tubes are amplifying voltage, and devices in the power supply are amplifying current? But the manual expressly disclaims that this is what is going on. So what is going on? (...)
Ron,

Although we do not have any details on the solid state output stage topology, the Alieno uses 2 x ECC82 for input and drive. The KT150's are used for the power stabilization, not for drive.
 

Ron Resnick

Site Co-Owner, Administrator
Jan 25, 2015
6,485
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Beverly Hills, CA
#7
If it has a solid-state output stage how in the world can the designer claim it is not a hybrid?

If it is a hybrid with a tube input stage and a solid-state output stage then the mysteries disappear.

And if this is a hybrid amplifier then either I was hearing fairly standard (excellent) hybrid amp transparency or I was suffering from significant OTL expectation bias, or both.
 

LL21

Well-Known Member
Dec 26, 2010
10,873
106
63
#8
Great writing and listening notes as usual! most interest to learn more about this amp. There was a time when CJ was 'announcing' a new SET 300b amp that had some insane amount of wattage power thru some form of unusual circuit design...let me see if i can find it and see if our more technical members can translate.
 

LL21

Well-Known Member
Dec 26, 2010
10,873
106
63
#9
Great writing and listening notes as usual! most interest to learn more about this amp. There was a time when CJ was 'announcing' a new SET 300b amp that had some insane amount of wattage power thru some form of unusual circuit design...let me see if i can find it and see if our more technical members can translate.
Found it...our own member XV1 posted it many years ago here...can any of our members explain the description below any further?

http://www.audioaficionado.org/showthread.php?t=9814&page=12


"turntable turntable is online now
Senior Member

Join Date: May 2009
Location: Downunder in Sydney
Posts: 1,752
Default
Remember this from CES 2003. Apparently cj have enough parts to make several pairs.



conrad-johnson GAT Amplifier ($38,000) is the company's first venture into 300B tube amplification. This is the only 300B amplifier that outputs 1,000 watts (not a typo). A low ratio transformer is coupled to a push-pull buffer. This keeps the voltage gain characteristics of a 300B but the current gain of the output buffer stage."



CJ 300B prototype.jpg
 

BMCG

VIP/Donor
Oct 1, 2016
204
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United Kingdom
#10
Ron - did you get a chance to A/B the Alieno versus what I assume are Momentum monos (at least they appear to be on the shelf under the screen)...? if so, any thoughts on the relative merits?

(btw my Dutch wife...who comes from the northeast of the Netherlands...was also curious as to where Lochem lay...fairer to describe as 2 hrs East of Amsterdam...)
 
Sep 7, 2016
250
259
63
Netherlands
#11
Thanks for your visit and quick review Ron, didn't expect that :).
About the Alieno Amp i understand the doubts. I'm looking quiet simple to it. I have it for a bit more than a year now. I fell in love with its sound after a few demo's and a few weeks in my own system. It had the musically flow and fullness i was looking for and power more than enough for me. And for the technical understanding, i am happy with the fact there are a lot designers who are much more clever than me :).
We discussed also here http://www.whatsbestforum.com/showthread.php?24422-Recommend-me-a-SS-pre/page5.
For those who want's to know more about the Alieno could contact Fabio Liberatore, info at therecorderman.com.
 

GMKF

VIP/Donor
Aug 15, 2017
397
48
28
Munich
#12
Thanks Ron for this review !
Im also wondering how this amp works...

@Audioquattr, is that some sort of Schnerzinger protector infront of your amp ?
If yes, can you please give your opinion on it ;)
 
Sep 7, 2016
250
259
63
Netherlands
#13
Thanks Ron for this review !
Im also wondering how this amp works...

@Audioquattr, is that some sort of Schnerzinger protector infront of your amp ?
If yes, can you please give your opinion on it ;)
Yes that's a Schnerzinger protector. I do like them, it improves detail and soundstage a little. Even bass (harmonics) sounds better.
 

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