StormAudio ISP 16 MK2 Review (AV Processor)

[apgood]

Thanks. Does the LAN input accept multichannel from Roon?

No it doesn't. They are looking whether they can get it to work with the existing hardware when I asked StormAudio support the same question

 

[apgood]

It is a modular design and any single board can be repaired or replaced. I upgraded my MK1 to a MK1.5 which included four new FPGA boards (not DSP chips) and a new decoder board. I also upgraded its HDMI board and have added AVB output. All US repair or upgrade is done in California.

I did the same with my MK1. I've upgraded it with the MK1.5 upgrade and the AES/EBU 32 Channel digital out module.
In both cases they were fine with me doing it based on understanding that if I break something in the process then it's on me. Quite reasonable really.

On the MK1.5 upgrade the longer cable to connect the AES/EBU module to the new cards was missing because the AES/EBU module wasn't registered on my serial number properly. They express couriered the cable to me with an hour of me logging the case then only after that asked why to work why it was missed. No need for me to justify why they should send it or who needs to pay for the shipping and or cable.

Great customer first mindset, especially since they are primarily geared to providing support through their dealer network.

 

[apgood]

Your assumption is correct. But implementations vary. Sometimes the position of the volume control makes no difference. Other times the firmware switches gain stages and produces different results based on position of the volume control. Here is an example:

I don't recall now why I did not run the storm at different volume levels. I ran the tests a few days ago and already forgot.

The MK2 version of the StormAudio that you reviewed also let's you select the type of Volume control on a per channel basis (either pure Analogue or Hybrid digital/analogue) which as I understand would further improve the SINAD. Think by default it is on Hybrid. This was introduced in the current firmware release v4.1R1. Was that the one you tested with and did you try setting it for the channels you tested to Analogue?

Edit:. Correction the choice of volume adjustment mode is only applicable if you have the AES/EBU module. The Analogue edition of the ISP you tested the volume control in the DAC board is designed to keep residual noise low. As low as 4uVrms based on the firmware 4.1R1 release notes. This is one of the improvements over the MK1.

 

[Bear123]

Your assumption is correct. But implementations vary. Sometimes the position of the volume control makes no difference. Other times the firmware switches gain stages and produces different results based on position of the volume control. Here is an example:

I don't recall now why I did not run the storm at different volume levels. I ran the tests a few days ago and already forgot.

What do these volume levels translate to in terms of a known reference i.e. reference level? (I *think* 80 is reference level(much louder than most listen)? so 90 would show performance for those that listen at 10 dB above reference level?)

 

[Anthony T]

Copy-paste from the 3rd paragraph:

"As is my common practice, when manufacturers send me something and I find problems, I provide feedback to them prior to publication".

Amir has stated that is the company sends it to him, he gives them the privilege of checking the measurements beforehand, and to make necessary changes if they see fit. Any changes would thus be in a software fix, so existing owners will benefit.

Thank you for your replies. Understood.

 

[Helicopter]

What do these volume levels translate to in terms of a known reference i.e. reference level? (I *think* 80 is reference level(much louder than most listen)? so 90 would show performance for those that listen at 10 dB above reference level?)

This depends on your speaker sensitivity, listening distance, and your amp power. You will probably need to measure it rather than calculate because specs vary.

 

[peng]

That's correct. It is a carrot for companies to send products in, rather than waiting for their customers to do so. I know there are pros and cons to this but that is my current strategy.

Amir, with the Stormaudio priced so high and it seems the soup up AVR-X8500H version, i.e. the A110 (only 13.1 capable) is getting some interests due to its 8K support, claimed "extensively tuned", and a 5 year warranty, but they do expect even better SINAD than the current ASR top ranked AVR. Would you be willing to ask your D+M contact to see if they can send you a demo for test? Potential additional carrot to letting them preview the results could be something like auction the demo if after the test, if the results in fact equal or better than the X8500H?

If they won't do it, then may be request them to publish their internal test results like they did for the SR8015.

 

[Haskil]

Oh my... This backplate looks so cheap for 15k.View attachment 122679

At last, close to decent performance for an AV processor! Software also seems to be next-level.

It is perfectly functional, it is in brushed and anodized aluminum; its thickness must be sufficient to support the XLR sockets that can be plugged into it ... This rear panel is also modular: it is very well thought out, sober, solid: it is perfect ... Personally, I have some a little enough of the hi-fi devices whose boxes or cases (for the speakers) are of such luxury that their cost price significantly affects the final selling price. This StormAudiio is expensive, sure, but its price comes mainly from the studies that went into its design and the fact that it is not manufactured in large quantities.

 

[peng]

This so called “hygiene” may easily result in intermodulations in the next amplifier, as the ultrasonic components are equal or well below 100kHz and thus below the action of the usual input RC filter. This is a bad feature and should not be overlooked by an experienced test person.

But in that case, wouldn't such components show up in the FFT and be included in the SINAD measured, if they are in fact within the audible band? THD+N/SINAD measurements only notch out the fundamental of the test signal right?

 

[peng]

So, the results may or may not reflect real life SINAD values. But I assume the regular THD+N, SINAD is always done with 0dBFS signal and with device's master volume adjusted to get 2V or 4V?

I think so too but may be Amir can reconfirm that (iirc he did before). Also, to you point about "real life SINAD..", I would think that at lower volume the value would most likely improve, based on the graphs (take a look of the linked pdf file, there are many more graphs) of the volume control IC (NJU72343) so the way Amir has been doing should represent the worse case scenario. It shows at higher Vin, it performs progressively worse at frequency >2 kHz but did do slightly but negligibly worse at the low frequencies. Either way the differences don't seem significant enough to be audible though. We already know the DAC IC is not the bottleneck but the Vol chip clearly could be even just base on specs. The switches, as bigguyca pointed out before, would also cause a little degradation too but not that much but those would be independent of the volume setting and input voltages.

8-Channel Electronic Volume: Audio Signal Processing (njr.com)

 

[Ron Texas]

It is a modular design and any single board can be repaired or replaced. I upgraded my MK1 to a MK1.5 which included four new FPGA boards (not DSP chips) and a new decoder board. I also upgraded its HDMI board and have added AVB output. All US repair or upgrade is done in California.

You make a good case that the unit is well built. I should have been clearer that my concern for being able to repair anything is the availability of proprietary replacement parts. The US repair facility is helpful.

 

[Andysu]

Does this AVP have a decent video colour settings for PAL/NTSC and aspect ratio settings that can be programmed into the memory for - VHS - Laserdisc - HD-DVD -bluray - 4k oh maybe 500k format I hear it's gonna be best yet?
So does this AVP have a serious video colour aspect ratio settings?

 

[Kal Rubinson]

No it doesn't. They are looking whether they can get it to work with the existing hardware when I asked StormAudio support the same question

ROON kommer att spela multikanal på Storm, datumet kunde inte nämnas av stödet ännu, dessutom kommer det att finnas möjlighet att fungera, till exempel för att hoppa i en spellista.

So it seems that StormAudio will support Roon/MCH soon (and as does Trinnov now).

 

[RichB]

But in that case, wouldn't such components show up in the FFT and be included in the SINAD measured, if they are in fact within the audible band? THD+N/SINAD measurements only notch out the fundamental of the test signal right?

Would you not have to start measuring amplifiers to determine immunity from out of band noise to know?

That same is true of noise or signal in HD Audio above 20 kHz. Some speakers may not be bothered but others may be.

The HD Audio "Keys" test is a good example. Credible folks have passed ABX tests.
Clearly, these people do not hear above 20kHz so something is happening in the audible range.
Bias comes in when we assume that different is showing efficacy.
It may show that their system was modulating what should in inaudible to become audible.
That does not sound good to me

IMO, design hygiene and out of band anomalies are to be avoided and should not the present in very expensive products.

- Rich

 

[Andysu]

$15 grand waste of money. If it can't do what I did when projectionist and react fast with video mode settings and sound formats then it is slower than a snail for $15 grand. I would wait 4 years for it to be on ebay for $100.00

 

[Blumlein 88]

$15 grand waste of money. If it can't do what I did when projectionist and react fast with video mode settings and sound formats then it is slower than a snail for $15 grand. I would wait 4 years for it to be on ebay for $100.00

How much would you charge for me to get you as my personal always available projectionist?

 

[Andysu]

How much would you charge for me to get you as my personal always available projectionist?

FOC. I once enjoyed doing it. But never mind the inflation that is just a word to make people crack up. I don't know, $5.00 per hour and that is cheap.

 

[peng]

Would you not have to start measuring amplifiers to determine immunity from out of band noise to know?

That same is true of noise or signal in HD Audio above 20 kHz. Some speakers may not be bothered but others may be.

The HD Audio "Keys" test is a good example. Credible folks have passed ABX tests.
Clearly, these people do not hear above 20kHz so something is happening in the audible range.
Bias comes in when we assume that different is showing efficacy.
It may show that their system was modulating what should in inaudible to become audible.
That does not sound good to me

IMO, design hygiene and out of band anomalies are to be avoided and should not the present in very expensive products.

- Rich

I agree with you that it should be avoided but I was responding to the specific point raised. ASR's THD+N were measured with 1 kHz signal but occasionally Amir did include the THD+N vs frequency that that one covers all the way to 20 kHz. The original question was about the distortions created by IMD in the supersonic range, and I believe such components would be captured in one of more of Amir's tests. For clarity, we are going to have to specify the frequency of such components that are originated from the IMD at the >>20,000 Hz range.

Your point about some speakers may be bothered by such "out of band" noise, I guess that is possible but it obvious depends on the magnitude and frequency so it may or may not be a practical issue. Again, need to know the specifics if we want to know for sure, but again, agree with you it is possible.

 

[amirm]

So, the results may or may not reflect real life SINAD values. But I assume the regular THD+N, SINAD is always done with 0dBFS signal and with device's master volume adjusted to get 2V or 4V?

That's correct. The level of volume control is indicated on the dashboard (-7.1 dB here).

 

[amirm]

About implementations: for example the Monoprice HTP-1 allows to separately adjust max. output voltage (reducing fixed gain after the analog volume control) but it's master volume control also adjusts digital headroom in addition to analog gain. But it adjusts digital headroom only to -11dB mv scale and below that it uses just analog gain. To fully measure such thing would take a long time.

Yeh, similar problem exists with measuring integrated amplifiers as to what volume control position to use vs input level.