Minidsp SHD Review Updated (DSP, DAC & Streamer)

[Sonnie]

You guys clearly do not understand what YouCanCallMeGeorge is trying to do. After acoustic measurements are taken and Dirac filters are generated we are measuring how much boost Dirac has applied. This has nothing to do with further acoustic measurements or verification of performance.

Michael

No problem... it's just not a concern of mine. Never had any issues with headroom and/or clipping my amps when using Dirac. However, as soon as I get my new recliner in... I won't be using Dirac anyway... I'll be using Audiolense via convolution filters in Roon.

 

[RichB]

No problem... it's just not a concern of mine. Never had any issues with headroom and/or clipping my amps when using Dirac. However, as soon as I get my new recliner in... I won't be using Dirac anyway... I'll be using Audiolense via convolution filters in Roon.

Can Audiolense filters be loaded into the SHD?

- Rich

 

[Sonnie]

Can Audiolense filters be loaded into the SHD?

- Rich

I suppose so... and might be better there vs Roon (probably doesn't matter, but). I'll have to ask Bernt to make sure, but I don't see why not.

 

[YouCanCallMeGeorge]

Would playing some sinewaves and measuring the voltage at some level with and without Dirac suffice?

- Rich

The goal is to compare the SHD output with Dirac off to the SHD output with Dirac on, across the full frequency range. The best way, and really the only practical way to do this is with an automated sweep, with the signal coming in via the USB port.

 

[win]

Can Audiolense filters be loaded into the SHD?

- Rich

you can put any biquad coefficients you want into the SHD DSP

 

[Sonnie]

The goal is to compare the SHD output with Dirac off to the SHD output with Dirac on, across the full frequency range. The best way, and really the only practical way to do this is with an automated sweep, with the signal coming in via the USB port.

I do this all the time with the REW sweep file... a before and after Dirac measurement. What am I missing?

 

[mdsimon2]

I do this all the time with the REW sweep file... a before and after Dirac measurement. What am I missing?

The goal is to directly measure the electrical transfer function being implemented by Dirac to prevent digital clipping in the SHD without any other additional uncertainty from acoustic measurements.

I agree with your previous statement that digital clipping is almost never an issue but some people on the miniDSP forum got pretty worked about this issue when they were getting clipping after applying Dirac when using downstream volume control. As a result miniDSP added a note to the SHD manual indicating that Dirac can boost up to 10 dB which a lot of folks misunderstand and are worried about.

By directly measuring how much boost the SHD is applying you can determine the exact amount to cut in the SHD to avoid digital clipping when using downstream volume control (or if you are using the SHD volume control determine above what volume you might get digital clipping). In almost all cases I've seen this cut is substantially less than 10 dB so folks that are blanket cutting 10 dB are losing quite a bit of output capability.

Michael

 

[CoolHandDuke]

When trying to integrate a single subwoofer with minidsp SHD, how does the software differentiate since you are telling both channels there's a sub? I hope this makes sense.

My sub is between mains, but close to right main. If I'm trying to set delay or run room correction, minidsp doesn't know it's the same sub, right? So it's applying 2 different corrections to same source? Perhaps I'm understanding this incorrectly.

 

[mdsimon2]

When trying to integrate a single subwoofer with minidsp SHD, how does the software differentiate since you are telling both channels there's a sub? I hope this makes sense.

My sub is between mains, but close to right main. If I'm trying to set delay or run room correction, minidsp doesn't know it's the same sub, right? So it's applying 2 different corrections to same source? Perhaps I'm understanding this incorrectly.

Short answer is it doesn't differentiate. The SHD is stereo only and has no knowledge that the sub is separate. The sub will be included in both the left and right sweep.

As the sub response will be the same in both the left and right sweeps it should have identical correction for left and right channels. I guess you might see some differences as presumably the crossover interaction to mains is different for left and right channels. One of the reasons that I use stereo subs.

This is also an area where you can run in to digital clipping issues. If you sum left and right for your sub in the SHD and the left and right input signal are identical (which is not a bad assumption for bass frequencies) the SHD will produce an output that is +6 dB when compared to a single channel.

Michael

 

[Pjetrof]

A question think this is best thread
i use only stereo so no subs
have pre and power amp
and cd with dac and optical in
just need room correction and streaming
wich dsp would you advise?

 

[Sonnie]

The goal is to directly measure the electrical transfer function being implemented by Dirac to prevent digital clipping in the SHD without any other additional uncertainty from acoustic measurements.

I agree with your previous statement that digital clipping is almost never an issue but some people on the miniDSP forum got pretty worked about this issue when they were getting clipping after applying Dirac when using downstream volume control. As a result miniDSP added a note to the SHD manual indicating that Dirac can boost up to 10 dB which a lot of folks misunderstand and are worried about.

By directly measuring how much boost the SHD is applying you can determine the exact amount to cut in the SHD to avoid digital clipping when using downstream volume control (or if you are using the SHD volume control determine above what volume you might get digital clipping). In almost all cases I've seen this cut is substantially less than 10 dB so folks that are blanket cutting 10 dB are losing quite a bit of output capability.

Michael

Thanks for the explanation... and that is understandable.

 

[RichB]

A question think this is best thread
i use only stereo so no subs
have pre and power amp
and cd with dac and optical in
just need room correction and streaming
wich dsp would you advise?

SHD products are not yet Roon Ready but you can use as a Roon Bridge.
The SHD (full) can replace your Pre but if you want to continue to use your CD as a DAC then the SHD Studio.

Depending on your CD and Preamp, the SHD (Full) might be an upgrade.

- Rich

 

[RichB]

ARGH!!!!

I received my SHD yesterday and started playing. Guess what, the USB Host output is turned off in StandBy and works perfectly well triggering the Benchmark AHB2 amps (or any other amp that responds to 5 volts). I also verified this with a USB power meter.

@Sonnie, too bad you bought a bunch of unnecessary work arounds.

I will try using a splitter which should permit the SHD plugin and trigger to work at the same time.

- Rich

 

[Sonnie]

ARGH!!!!

I received my SHD yesterday and started playing. Guess what, the USB Host output is turned off in StandBy and works perfectly well triggering the Benchmark AHB2 amps (or any other amp that responds to 5 volts). I also verified this with a USB power meter.

@Sonnie, too bad you bought a bunch of unnecessary work arounds.

I will try using a splitter which should permit the SHD plugin and trigger to work at the same time.

- Rich

Well this is awesome news Rich... and I can send the BobWire back to Amazon (they offer FREE Return with this item). I don't use the WiFi dongle.

 

[Sonnie]

I wonder if this cable will work... or does it have to be a mono tip? EDIT: I see in the AHB2 Manual it show TRS... so this should work.

Or I suppose I could use an adapter with the provided 3.5mm cables from Benchmark.

 

[RichB]

I wonder if this cable will work... or does it have to be a mono tip? EDIT: I see in the AHB2 Manual it show TRS... so this should work.

View attachment 107177


Or I suppose I could use an adapter with the provided 3.5mm cables from Benchmark.

View attachment 107179

It's worth a try. Tip is positive. Where did you find that cable?

I was going to make a shorter cable tonight. The cable I had has two trigger cables and is loner than I need.

- Rich

 

[Sonnie]

It's worth a try. Tip is positive. Where did you find that cable?

I was going to make a shorter cable tonight. The cable I had has two trigger cables and is loner than I need.

- Rich

https://www.amazon.com/gp/product/B07DS97412/ref=ox_sc_act_title_1?smid=A3SP9D0HBLLG4I&psc=1

Amazon... and of course I could make one... I have plenty of extra USB cables and plenty of 3.5mm cables.

What two wires on the USB should be used on the 3.5mm?

 

[Sonnie]

I can test it with my volt meter, but my guess is it will be the red and black wires... out of the red, black, green and white.

 

[RichB]

https://www.amazon.com/gp/product/B07DS97412/ref=ox_sc_act_title_1?smid=A3SP9D0HBLLG4I&psc=1

Amazon... and of course I could make one... I have plenty of extra USB cables and plenty of 3.5mm cables.

What two wires on the USB should be used on the 3.5mm?

Red is +5 volts, black is ground, leave the data cables unconnected. So Red goes to the tip.

- Rich

 

[Sonnie]

Red is +5 volts, black is ground, leave the data cables unconnected. So Red goes to the tip.

- Rich

Got it... thanks!