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VTV Purifi Amplifier With SIL 994EnH-Ticha Pro Buffer Review

amirm

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This is a review and detailed measurements of the VTV Purifi class D amplifier with SIL 994EnH-Ticha Pro Opamp buffer stage (one of the options). It is on kind loan from a member and costs US $1,845 in this configuration.

It was love at first sight when I saw this rack mounted case with handles:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp review.jpg


Yes, the amp is light so the handles are really not needed but it is cool nevertheless. :) Speaking of cool, the amplifier never warmed up in any of my tests.

Typical of this class of amplifier, only balanced XLR inputs are provided:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp back panel balanced review.jpg


There is an option for SpeakOn speaker terminals.

We already know the measurements of the Purifi amplifier Reference Design. Question is whether the assembly and choice of SIL op-amp has an impact on the measured performance.

NOTE: I mistakenly labels the original review and graphs as 990Enh. It is actually 994Enh.

VTV Purifi Amplifier with SIL Buffer Measurements
As usual we start with our 5 watt dashboard into 4 ohm load:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Measurements.png


Gosh, that ugliness in the FFT spectrum really makes you lose your appetite coming from squeaky clean reference design:

index.php


The noise is triggered by the power supply. Whether op-amp is the source of the power supply or combination of both is hard to say. What is not hard to say is that we have lost some performance which also shows up in SNR:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp SNR Measurements.png


Fortunately performance is still superb in grand scheme of things:

best purifi amplifier review.png


Crosstalk thankfully is as excellent as the reference design:
VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Crosstalk Measurements.png


Frequency response however is truncated a bit:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Frequency Response Measure...png


Power levels are the same as reference:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Poer into 4 ohm Measurements.png


VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Poer into 8 ohm Measurements.png


I did not run the peak and max power at the time of the original review so we have some new data points:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Max and Peak Poer into 4 o...png


As well as this test for frequency sensitivity:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Power into 4 ohm vs freque...png


I will have to run this on Purifi reference at some point to see how it did. I am thinking the buffer is messing this up right now.

Finally, multitone test which clearly shows power supply related spikes:

VTV Purifi Amplifier with Sonic Imagery Labs 990EnH-Ticha Pro Opamp Multitone Measurements.png


Conclusions
VTV had me happy with its case work. Alas, the buffer as chosen appears to drag the pristine performance Purifi module down. Despite that, overall excellence of Purifi engineering still shows, allowing this amp to still outperform some 140 amplifiers tested to date!

I can't recommend the VTV with the buffer as chosen. Hopefully other variations don't leave performance on the table this way.

Edit: see the teardown here: https://www.audiosciencereview.com/...er-teardown-sil-990enh-ticha-pro-opamp.24861/

------------
As always, questions, comments, recommendations, etc. are welcome.

My daily routine is to eat dinner and then go to the garden and work and work and work. Come back in all sweaty. Clean up and then do reviews like you see. It is a very strenuous routine than makes me wonder why I do it. Then I see a cucumber like this in the greenhouse and it makes it all (almost) worthwhile!

Cucumber in greenhouse.jpg


Can't find stuff like this in the grocery story. Letting it grown for a couple more days before eating it!

Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 
Last edited:

Feyire

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Could you show us images of the inside? I'm curious to see the power supply position and orientation.
 
OP
amirm

amirm

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Could you show us images of the inside? I'm curious to see the power supply position and orientation.
Yes, I have permission to do that. It is past midnight though so will do tomorrow...
 

Phorize

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This is a review and detailed measurements of the VTV Purifi class D amplifier with SIL 990EnH-Ticha Pro Opamp buffer stage (one of the options). It is on kind loan from a member and costs US $1,845 in this configuration.

It was love at first sight when I saw this rack mounted case with handles:

View attachment 140237

Yes, the amp is light so the handles are really not needed but it is cool nevertheless. :) Speaking of cool, the amplifier never warmed up in any of my tests.

Typical of this class of amplifier, only balanced XLR inputs are provided:

View attachment 140238

There is an option for SpeakOn speaker terminals.

We already know the measurements of the Purifi amplifier Reference Design. Question is whether the assembly and choice of SIL op-amp has an impact on the measured performance.

VTV Purifi Amplifier with SIL Buffer Measurements
As usual we start with our 5 watt dashboard into 4 ohm load:

View attachment 140240

Gosh, that ugliness in the FFT spectrum really makes you lose your appetite coming from squeaky clean reference design:

index.php


The noise is triggered by the power supply. Whether op-amp is the source of the power supply or combination of both is hard to say. What is not hard to say is that we have lost some performance which also shows up in SNR:

View attachment 140241

Fortunately performance is still superb in grand scheme of things:

View attachment 140242

Crosstalk thankfully is as excellent as the reference design:
View attachment 140243

Frequency response however is truncated a bit:

View attachment 140244

Power levels are the same as reference:

View attachment 140245

View attachment 140246

I did not run the peak and max power at the time of the original review so we have some new data points:

View attachment 140247

As well as this test for frequency sensitivity:

View attachment 140248

I will have to run this on Purifi reference at some point to see how it did. I am thinking the buffer is messing this up right now.

Finally, multitone test which clearly shows power supply related spikes:

View attachment 140249

Conclusions
VTV had me happy with its case work. Alas, the buffer as chosen appears to drag the pristine performance Purifi module down. Despite that, overall excellence of Purifi engineering still shows, allowing this amp to still outperform some 140 amplifiers tested to date!

I can't recommend the VTV with the buffer as chosen. Hopefully other variations don't leave performance on the table this way.

------------
As always, questions, comments, recommendations, etc. are welcome.

My daily routine is to eat dinner and then go to the garden and work and work and work. Come back in all sweaty. Clean up and then do reviews like you see. It is a very strenuous routine than makes me wonder why I do it. Then I see a cucumber like this in the greenhouse and it makes it all (almost) worthwhile!

View attachment 140250

Can't find stuff like this in the grocery story. Letting it grown for a couple more days before eating it!

Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

There we have it, the difference between product engineering and stuffing components into a box and calling it a day.
 

abdo123

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how can someone mess such a straight forward design?

The 'reference' design literally looked like anyone can do it with access to documentation from Purifi.

the THD+N frequency dependency is just nasty, the whole point behind buying a 2000$ Purifi amp is to have Class D power that does not exhibit such behavior.
 

Tks

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A bit off topic, but it's just funny to see how long Benchmark holds a visually distinct lead in the SINAD chart over other power amps. Half decade now, and still nothing in sight..

@JohnYang1997 You guys still have your sights set on that crown?

Lol btw, what is that panther
 

VintageFlanker

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The noise is triggered by the power supply. Whether op-amp is the source of the power supply or combination of both is hard to say.
What about the reference design being cherry-picked two years back?
 

jae

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A bit off topic, but it's just funny to see how long Benchmark holds a visually distinct lead in the SINAD chart over other power amps. Half decade now, and still nothing in sight..

@JohnYang1997 You guys still have your sights set on that crown?

Lol btw, what is that panther

At 100W, but I feel there's no real reason to prefer the benchmark over purifi for SINAD alone if you're using 180-220W+ @ 4 ohm, especially at almost double the price or more (assuming reference design and their own specsheet).
 

Jim Matthews

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Yes, I have permission to do that. It is past midnight though so will do tomorrow...
A garden tour, please.

(While everything is in bloom. Set to the theme music of your favorite Disney Princess as a plus...)
 

Matias

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Last edited:

pma

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will have to run this on Purifi reference at some point to see how it did. I am thinking the buffer is messing this up right now.

No. The analog buffer will never have such bad higher frequency distortion. It is a system or amplifier wiring topology issue. These companies are a mere assemblers without deeper insight. It is a shame where the audio has ended.
 

Matias

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No. The analog buffer will never have such bad higher frequency distortion. It is a system or amplifier wiring topology issue. These companies are a mere assemblers without deeper insight. It is a shame where the audio has ended.
Agreed. When their only job is assembling modules in a box, the least they should do is measure the end result to see if they routed everything properly.
 

Koeitje

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Count Arthur

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Except the Purifi outperforms the NC400 in all areas but SINAD at 1KHz/5W/4Ohms. ;)

Fair point, and I imagine you'd have a hard time hearing much difference between any of the Hypex and Purifi amps clustered at the top of the list. However, I think the NC400 is significantly cheaper than the Purfi modules, which would make it the best value for money - possibly. :)
 
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