Sound of Zenquito

[ABO]

Some time ago I started a thread inquiring about Zenquito evolution. It resulted in me deciding to build one and promising to report my findings.

Well the amp is finished now. I can only compare the sound against my old amp, Elektor's IGBT-amp (nonante in French). I had hoped that Zenquito would be a worthwhile upgrade because I had read a lot of positive things about the amp, mostly in a French forum.
In comparison, Zenquito sounds less dynamic, less transparent and somewhat muddy in the midrange. And completely flat soundstage.
In another thread someone compared the sound of amps with muddy ponds and crystal clear mountain lakes. Zenquito obviously is of the former type. I'm sure it can sound good to some, but not to me. It has no special timbre of emotional engagement at all. To me it just sounds uninteresting.

In short: I don't like the amp. I really don't understand why people like this amp. I hope that someone can explain what it is he likes about the sound, I'm very interested.

Perhaps there is something wrong of course. I attached some pictures. If anyone can come up with improvements or sees any mistakes I may have made, please let me know.

ABo

[ABO]

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[ABO]

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[Zen Mod]

& your speakers are?

[ABO]

Hi Choky,

Do you think it would matter. I compared both amps in exactly the same setup. Are there any known issues with Zenquito that makes the amp sensitive for speaker load?

Anyway here it goes:

http://home.hetnet.nl/~geenius/HATT-III.html


ABo

BTW: This experience got me thinking. In France there is a community of people who all really like this amp, just like we have a community of people, here in DIYaudio, who all just love Aleph's.

Aleph and Zenquito share some technical similarities too: fairly high THD and similar distortion spectrum. My experience with Zenquito is corresponds exactly with the remarks PMA makes about Alephs. Of course it could be I'm plain deaf or just wrong, but it seems to me that the entire Aleph/Pass thing may well be a severe case of groupthink.

Disclaimer to all Passfans: I actually never listened to an Aleph or any other Passlabs amps.

[Jay]

Even though I have never built the Zenquito, I believe that the
speaker does matter, and so is pre-amp. This amplifier reminds
me of some MOSFET amps I have ever built including the Crescendo.

What you have described was just the "signature" of MOSFET amps
running in class B and with relatively short path (amplification
stage). I have heard that this amp is only a little better than
the crescendo (but that's just somebody's opinion).

Assumming that this amp is similar with those MOSFET amps, especially
the crescendo, you need at least 8" woofer of Peerless quality, or
a floorstander. 3-way is better, may be because the amp is not good
at mid (muddy).

MOSFET usually have low transconductance. I believe this makes it
dificult to match with many speakers to get an interesting sound.

And of course, you cannot compare such amps with Alephs. May be
MOSFET is good only in class A???

[Zen Mod]

simple amp need simple speaker
off course-meaning on highish efficiency and friendly impedance modul

[till]

as i understand - there are speakers of a kind that need a lot of power and a lot of damping factor.

And there are speakers of a kind that makes a lot of SPL with a few Watts and do not need much damping factor.


You say aleph, Zen etc, have a lot of THD. Thats not true. You compare numbers at full load or substancial amount of Watts. I measured ZEN 4 against chipamps. The truth is the Zen, aleph etc. has very very low THD at low power, growing with power you pull out of them. The chipamps are different, THD is significantly higher than Zen at low power levels, goes to very low values for something like 10% to 100% nominal power. As my speakers for example need something about 200mW for normal listening, a Zen or Aleph is much better in THD...

[fab]

Originally posted by till
as i understand - there are speakers of a kind that need a lot of power and a lot of damping factor.

And there are speakers of a kind that makes a lot of SPL with a few Watts and do not need much damping factor.


You say aleph, Zen etc, have a lot of THD. Thats not true. You compare numbers at full load or substancial amount of Watts. I measured ZEN 4 against chipamps. The truth is the Zen, aleph etc. has very very low THD at low power, growing with power you pull out of them. The chipamps are different, THD is significantly higher than Zen at low power levels, goes to very low values for something like 10% to 100% nominal power. As my speakers for example need something about 200mW for normal listening, a Zen or Aleph is much better in THD...

The increase on THD as the power increases is an effect of lower feedback amp design (as I have experienced).
You really listen to 200mW! You must have efficient small speakers? Regarding THD criteria, you probably already know as it is mentioned a lot on this forum that it is only one of many criteria and probably not the most important.

Regards,

Fab

[jam]

ABO,

There are a couple of ways to improve the sound of Zenquito. One is to run yhe front end off it's own bridge rectifier and possibly regulate it and the other option is to increase the bias.

Regards,
Jam