> But there is one exception. The AH578 LATFET
Speaking of LATFETs - I just ordered 50 N and 50 P dual die matched latfets from Profusion/Exicon. I had to pay a pretty penny for this order, but it's just in case they gonna stop making them..
So I guess at least some of the next amps in the future, will be latfets...
This whole business of matching vertical fets, put me off...
Speaking of LATFETs - I just ordered 50 N and 50 P dual die matched latfets from Profusion/Exicon. I had to pay a pretty penny for this order, but it's just in case they gonna stop making them..
So I guess at least some of the next amps in the future, will be latfets...
This whole business of matching vertical fets, put me off...
So I have been listening to this latest amp (post #1537, #1471, #1568) for a few days now.
Did a preliminary review (post #1568), but as we all know, no one can consider this kind of review
as sufficient. Proper amp review requires to use some serious music.
Not 'Dick in the Box' or 'Happy Birthday' song performed by Argentinian folk band.
Everyone knows, that serious amp requires serious music to be truly appreciated and evaluated.
So question is - what music deserves to be played here?
This music should truly reveal all the best features of the amp,
and at the same time - make the reviewer to look like person who is sophisticated, cultured, and with style.
So here are my impressions:
The first time I picked up my fountain pen to make some notes, I was listening to Pérotin's Beata viscera Mariae Virginis,
sung by the Sistine Chapel Choir directed by Massimo Palombella, on their Veni Domine: Advent & Christmas at the Sistine Chapel.
It sounded stunning through this amp, which effortlessly conveyed this recording's outstanding sound quality.
Mezzo-soprano Cecilia Bartoli is featured on this track, and her performance was mesmerizing - the amp's exceptional clarity
and smooth, extended treble revealed her delicacy and nuance.
Part of what makes this recording so captivating is that it conveys the spaciousness of the Sistine Chapel - it's
easy to hear Bartoli's higher notes resonate against the walls and what is arguably the most famous
ceiling of Western culture.
It's difficult to overstate the importance of space in this music - it communicates an incredible amount,
both sonic and emotional. When the voices enter the soundstage, the acoustic fills out even more, expanding even
farther the size of the stage, which again expands later on. Sound this extraordinary can only be the
result of exemplary skills in recording, and Deutsche Grammophon's engineers deserve praise for it.
However, the fidelity of the playback system is also crucial, if the listener is to hear what the producer and
engineers have set out to achieve - and this is where praise is due this new amp.
I haven't tested a flagship amplifier of this calibre in a while, so I moved on to Presto of Haydn's String Quartet in D Major, Op.76 No.5,
performed by the Engegård Quartet (SACD/CD, 2L Sampler 2009, 2L), offered a better example of the ease and clarity
with which the amp handled dynamic shifts.
Granted, these weren't the grand, chest-thumping, jolt-you-from-your-chair explosive dynamic swings of an orchestral
piece such as the War Dance from Respighi's Belkis, Queen of Sheba: Suite, with Eiji Oue conducting the Minnesota
Orchestra (CD, Reference RR95CD) - which, incidentally, the amp also handled with aplomb - rather, these were microdynamic changes.
Resolving them so cleanly revealed a genuineness to the sound of violin bows as they coaxed notes from the strings;
likewise, the rich, woody resonances that emerged from the body of the cello. I was left with the feeling that I was hearing
more of the music, and less of the electronic editorializing unavoidable in playing a recording through a system rather than
attending a live concert. While the sound one hears at home through a stereo will always result from a combination of the
recording, the playback system, and the listening room.
Techincally speaking, this amp decidedly minimizes error vectors, and at the same time makes the group delay constant.
Or is it the other way around. No one knew it was even possible.
Even if there is one or two of these vectors not minimized completely, at least they are pointing
into the same direction.
Sorry for lengthy post, but certain things needed to be said about this amp.
Did a preliminary review (post #1568), but as we all know, no one can consider this kind of review
as sufficient. Proper amp review requires to use some serious music.
Not 'Dick in the Box' or 'Happy Birthday' song performed by Argentinian folk band.
Everyone knows, that serious amp requires serious music to be truly appreciated and evaluated.
So question is - what music deserves to be played here?
This music should truly reveal all the best features of the amp,
and at the same time - make the reviewer to look like person who is sophisticated, cultured, and with style.
So here are my impressions:
The first time I picked up my fountain pen to make some notes, I was listening to Pérotin's Beata viscera Mariae Virginis,
sung by the Sistine Chapel Choir directed by Massimo Palombella, on their Veni Domine: Advent & Christmas at the Sistine Chapel.
It sounded stunning through this amp, which effortlessly conveyed this recording's outstanding sound quality.
Mezzo-soprano Cecilia Bartoli is featured on this track, and her performance was mesmerizing - the amp's exceptional clarity
and smooth, extended treble revealed her delicacy and nuance.
Part of what makes this recording so captivating is that it conveys the spaciousness of the Sistine Chapel - it's
easy to hear Bartoli's higher notes resonate against the walls and what is arguably the most famous
ceiling of Western culture.
It's difficult to overstate the importance of space in this music - it communicates an incredible amount,
both sonic and emotional. When the voices enter the soundstage, the acoustic fills out even more, expanding even
farther the size of the stage, which again expands later on. Sound this extraordinary can only be the
result of exemplary skills in recording, and Deutsche Grammophon's engineers deserve praise for it.
However, the fidelity of the playback system is also crucial, if the listener is to hear what the producer and
engineers have set out to achieve - and this is where praise is due this new amp.
I haven't tested a flagship amplifier of this calibre in a while, so I moved on to Presto of Haydn's String Quartet in D Major, Op.76 No.5,
performed by the Engegård Quartet (SACD/CD, 2L Sampler 2009, 2L), offered a better example of the ease and clarity
with which the amp handled dynamic shifts.
Granted, these weren't the grand, chest-thumping, jolt-you-from-your-chair explosive dynamic swings of an orchestral
piece such as the War Dance from Respighi's Belkis, Queen of Sheba: Suite, with Eiji Oue conducting the Minnesota
Orchestra (CD, Reference RR95CD) - which, incidentally, the amp also handled with aplomb - rather, these were microdynamic changes.
Resolving them so cleanly revealed a genuineness to the sound of violin bows as they coaxed notes from the strings;
likewise, the rich, woody resonances that emerged from the body of the cello. I was left with the feeling that I was hearing
more of the music, and less of the electronic editorializing unavoidable in playing a recording through a system rather than
attending a live concert. While the sound one hears at home through a stereo will always result from a combination of the
recording, the playback system, and the listening room.
Techincally speaking, this amp decidedly minimizes error vectors, and at the same time makes the group delay constant.
Or is it the other way around. No one knew it was even possible.
Even if there is one or two of these vectors not minimized completely, at least they are pointing
into the same direction.
Sorry for lengthy post, but certain things needed to be said about this amp.
Thanks for the detailed review. It was very helpful to read. However, I also like how Bryston B135 and Denon AVC-X8500H sound.
I was checking temperatures on the board, and I discovered that Zener resistors (3k) are running at 90 degrees C.
Kind of hot. They will be fine for up to 200 degrees, but they are heating up their neighbors (e.g. small electrolytic caps).
Not good.
I guess on the PCB there should be a lot of free space around them, especially no electrolytics in the proximity.
According to the sim, they are dissipating 400mW each, and the resistors are 1W, but small in size.
I guess that's how resistor makers makes them small - let them run hot.
Bigger surface would cool faster.
Kind of hot. They will be fine for up to 200 degrees, but they are heating up their neighbors (e.g. small electrolytic caps).
Not good.
I guess on the PCB there should be a lot of free space around them, especially no electrolytics in the proximity.
According to the sim, they are dissipating 400mW each, and the resistors are 1W, but small in size.
I guess that's how resistor makers makes them small - let them run hot.
Bigger surface would cool faster.
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TL431 is a replacement of a Zener, not of the resistor.
Regardless of what you use, (50V - 15V) * 12mA of heat has to be dissipated somehow/somewhere.
If it's dissipated from small surface - it will run hot.
If it's dissipated from large surface - it will run cooler.
Just like heatsinks.
Resistor is fine, but:
a) better be big size
b) far away from capacitors (and other devices).
Theoretically all caps next to it, should be fine with 90 degrees, but it's borderline...
If I have to, will re-solder them leaving longer legs (wires), so they are upper in the air to help cooling.
Regardless of what you use, (50V - 15V) * 12mA of heat has to be dissipated somehow/somewhere.
If it's dissipated from small surface - it will run hot.
If it's dissipated from large surface - it will run cooler.
Just like heatsinks.
Resistor is fine, but:
a) better be big size
b) far away from capacitors (and other devices).
Theoretically all caps next to it, should be fine with 90 degrees, but it's borderline...
If I have to, will re-solder them leaving longer legs (wires), so they are upper in the air to help cooling.