StormAudio ISP MK2 24CH AV Processor Review & Support Thread

[AcuDefTechGuy]

Andrew is in Dallas, with family. He about to eat a Big giant Texas steak! If his wife let's him.

Went to Osaka in Dallas. Just realized they jacked up the buffet price to $40/person.

 

[Danzilla31]

Went to Osaka in Dallas. Just realized they jacked up the buffet price to $40/person.

That's better then Chauma De Gaucha here in San Antonio its over 50 bucks a person

 

[AcuDefTechGuy]

That's better then Chauma De Gaucha here in San Antonio its over 50 bucks a person

I haven’t been to those Vegas buffets in a while. They’re probably $100/person now. Damn the inflation.

 

[gene]

You and Gene are funny, but in an engineers way. I got it PENG, I lol when I read Gene's post to you on the calculator thing. On AH, You, Gene for sure of course, Doc and maybe a few other's know the math when comes to audio. The rest of us need calculators some of us just don't think as fast as you guys.

I had to help my daughter multiplying/dividing and simplifying exponents tonight. It's amazing how much you forget when you don't use it. Believe me, calculators like Peng linked to, I use all the time.

 

[PENG]

I had to help my daughter multiplying/dividing and simplifying exponents tonight. It's amazing how much you forget when you don't use it. Believe me, calculators like Peng linked to, I use all the time.

Haha, the truth always comes out.. Anyway Gene, tell you the truth, I knew from years ago when I first joined AH, that I had finally found a site owned by an ex communication systems (aka telecommunication) engineer. I felt good about finding your website, because I knew no one could graduate and actually practice in that field without really understanding some of the toughest to grasp EE theories and mathematics involved. I could pass exams in U but couldn't say I understood what the heck Fourier, Laplace, Z-Transforms etc., also Curl, Div, Grad, (curvilinear and vector calculus.. on the mechanical side. Electromagnetic and field theory were also tough. It was not until I had to take a course in communication systems at the U of T to pass one of the exams required to get my license that I really got what Fourier was about. How can anyone talk much about square wave, THD+N analysis without understanding Fourier?

I kept my oldest book (had bought a few more text books as I got so interested in the subject by then) in later years) on communication systems and just found that even the new edition is now dated, 2008..
Highly recommended for audioholics who are interested in the EE basics applicable to everything audio. ADTG should try just for fun.

 

[PENG]

Hello Gene,

Isn't the Y-axis THD+N, not THD?

 

[ryanosaur]

I had to help my daughter multiplying/dividing and simplifying exponents tonight. It's amazing how much you forget when you don't use it. Believe me, calculators like Peng linked to, I use all the time.

Ha! When I was in high school and my dad (he was an EE) was still working, he hated helping me with algebra and the like for just that reason! Fast forward to my playing around with my first XO circuit 2 years back and him being retired for many years; it was like I was asking him to explain wave theory to me when I pestered him a little to help me understand building a basic circuit.

 

[Eppie]

Anyone else watch 3Blue1Brown on YouTube for fun?

 

[panteragstk]

That's true but it's also the only room correction system that virtually does nothing so there's that

Lol. I can just see Yamaha's marketing team spinning this around.

"YPAO, so transparent you can't tell if it did anything at all."

"YPAO, the only ARC system that doesn't downsample your audio. Why change perfection?"

Customers rave about YPAO:

"wow, when I enabled YPAO the first time, it was like everything was exactly the same!"

"...I don't get it"

 

[panteragstk]

I had to help my daughter multiplying/dividing and simplifying exponents tonight. It's amazing how much you forget when you don't use it. Believe me, calculators like Peng linked to, I use all the time.

My kids are all little (grade 1 and 2) so their math is so easy it's silly. Except the way they teach it now is just odd.

I studied EE in college, but never worked as one. Same reason @AcuDefTechGuy changed over. Too many in the field at the time.

It worked out, but I've forgotten so much math it makes me feel dumb to look at things I used to understand instantly. Getting older doesn't help either.

Use it or lose it!

 

[PENG]

I studied EE in college, but never worked as one. Same reason @AcuDefTechGuy changed over. Too many in the field at the time.

Probably more lawyers than EEs now.

 

[ryanosaur]

Coding and network/it is the way to go these days. Even today, long after many years of music school, I still joke that my dad should’ve made me learn to code. *shrugs

 

[panteragstk]

Coding and network/it is the way to go these days. Even today, long after many years of music school, I still joke that my dad should’ve made me learn to code. *shrugs

True, but I hate coding. My brain isn't a fan of the tediousness.

However, I still have to learn scripting and such so I guess I couldn't escape it either.

 

[gene]

Hello Gene,

Isn't the Y-axis THD+N, not THD?

View attachment 52274

You're right and that measurement looks worse than it really is. Someone send me a link to Amir's commentary about this and I looked over my other measurements I didn't publish.

What this graph is actually showing is a combination of the down-sampling behaviour, anti-aliasing filters and the fact that my measurement is wide bandwidth. Sadly I didn't save the limited BW measurement and I don't want to rip the unit out of my rack to remeasure until StormAudio does the DAC upgrade.

I updated the text under that measurement as follows:

Update 12/13/21: A thread at ASR was brought to my attention discussing the above measurement with Amir and based on the comments there, I revisted and updated the text below.

The above sweep shows frequency response vs distortion which is exceedingly low at 0.002% THD+N (or 94dB SINAD). The distortion spikes above 5kHz are mostly due to a measurement anomaly caused by a combination of the down-sampling behavour, anti-aliasing filters and the fact that my measurement is wide bandwidth. It is likely so pronounced due to the high input sampling rate and the StormAudio ISP MK2 downsampling to 48Khz and not having usable output above 22kHz. I didn't see this many spikes when sampling at 48kHz but sadly I didn't save that measurement to replace the one above. It’s also still at 0.05% THD+N at 20kHz so still relatively low. I’d like to see better results here but an improvement may likely NOT be audible in most scenarios for even those audiophiles with the best of hearing. StormAudio has informed me a DAC upgrade is in the works slated for sometime in the near future with a possible higher sampling rate offered too. I will be revisiting these measurements once I get the upgrade module installed.

 

[AcuDefTechGuy]

My kids are all little (grade 1 and 2) so their math is so easy it's silly. Except the way they teach it now is just odd.

I studied EE in college, but never worked as one. Same reason @AcuDefTechGuy changed over. Too many in the field at the time.

It worked out, but I've forgotten so much math it makes me feel dumb to look at things I used to understand instantly. Getting older doesn't help either.

Use it or lose it!

After Eng. Math-I, I actually worked as a math tudor for a year, tutoring students from algebra to trig to calculus to Eng-Math.

But now forget it. You don't use it everyday, you lose it. Just like everything else in life.

 

[PENG]

What this graph is actually showing is a combination of the down-sampling behaviour, anti-aliasing filters and the fact that my measurement is wide bandwidth. Sadly I didn't save the limited BW measurement and I don't want to rip the unit out of my rack to remeasure until StormAudio does the DAC upgrade.

I updated the text under that measurement as follows:

Thank you for updating the text to ease concerns some readers may have, when they see those 5 kHz and up distortion/noise spikes and the fact that you mentioned "DAC upgrade". 192 kHz sampling is indeed a very wide bandwidth, a whopping 96 kHz! So everything above 20 kHz up to 96 kHz, whether they are distortion, noise or both, all would have been captured, and the AP would have total things up and report them as THD+N.

The 0.05% THD, or THD+N at 20 kHz or even at 5 kHz would likely be made up of distortions and/or noise (looks more like noise) outside the audio band anyway. The second harmonic of 20 kHz is 40 kHz, is well into the ultrasonic band, nothing to worry about even without the DAC upgrade that they are supposedly planning on doing.

 

[gene]

Thank you for updating the text to ease concerns some readers may have, when they see those 5 kHz and up distortion/noise spikes and the fact that you mentioned "DAC upgrade". 192 kHz sampling is indeed a very wide bandwidth, a whopping 96 kHz! So everything above 20 kHz up to 96 kHz, whether they are distortion, noise or both, all would have been captured, and the AP would have total things up and report them as THD+N.

The 0.05% THD, or THD+N at 20 kHz or even at 5 kHz would likely be made up of distortions and/or noise (looks more like noise) outside the audio band anyway. The second harmonic of 20 kHz is 40 kHz, is well into the ultrasonic band, nothing to worry about even without the DAC upgrade that they are supposedly planning on doing.

Yea it's fine, though still not SOTA but not bad. I don't use the DAC for the front LCR's since I have the separate Marani DSP running for the active speaker setup.

 

[PENG]

Yea it's fine, though still not SOTA but not bad. I don't use the DAC for the front LCR's since I have the separate Marani DSP running for the active speaker setup.

Actually I almost forgot how much this thing costs. With that in mind, I actually do think they need to upgrade the DAC section if that is what they need to get SOTA measurements.

 

[gene]

Actually I almost forgot how much this thing costs. With that in mind, I actually do think they need to upgrade the DAC section if that is what they need to get SOTA measurements.

Absolutely. I always test at 192khz and get better results on product that doesn't Downsample to 48khz. They can do better.

 

[DJ7675]

You're right and that measurement looks worse than it really is. Someone send me a link to Amir's commentary about this and I looked over my other measurements I didn't publish.

What this graph is actually showing is a combination of the down-sampling behaviour, anti-aliasing filters and the fact that my measurement is wide bandwidth. Sadly I didn't save the limited BW measurement and I don't want to rip the unit out of my rack to remeasure until StormAudio does the DAC upgrade.

I updated the text under that measurement as follows:

Thanks for updating the review. Without it, it seems there is an issue in the over 5k range, when it is something that will only show up in wideband measurements. While Trinnov seems to get quite a bit of the buzz in the high end processor market, I too opted for it over the Trinnov.