miniDSP users read this.

[Bob Brines]

My opinion of miniDSP is HERE.

Bottom line is that miniDSP is too noisy to take seriously.

Bob

[weinstro]

Re: miniDSP users read this.

Hi Bob,

Are you powering the miniDSP via USB? If so, try an external power supply. If you don't have one of those lying around, a 12 volt battery would work, just make sure that you don't short it out.

Regards,

Rob

[charlielaub]

Re: miniDSP users read this.

Hmmm, very interesting. I will have to try some similar measurements on my own MiniDSP units. Which one did you take measurements on?

I would wait to see what others report before writing off ALL MiniDSPs like you have done. That seems a little premature.

-Charlie

[MSaturn]

Re: miniDSP users read this.

I've never had a problem; I use the 12 volt supply.

(could very well be a QC issue, though)

[Wushuliu]

Re: miniDSP users read this.

My opinion of miniDSP is HERE.

Botton line is that miniDSP is too noisy to take seriously.

Bob

Also would be good to specify which one. Noise has been reported with use of the larger (2x8?) models, but not so much for the 2x4. I did not notice any noise with the 2X4.

[GranteedEV]

Re: miniDSP users read this.

Bob, are you using a balanced miniDSP or unbalanced, and what power supply are you using?

[Bob Brines]

Re: miniDSP users read this.

I am using the miniDSP-in-a-box, i.e. 2xunbalanced in, 4xunbalanced out. I am powereing off on my laptop, what I am lookking at can't possibly be due to a noisy power supply. the WTPro is also powered by the laptop. If it was a power supply problem, it would show on both. Extreme 3rd order distortion, occationally in excess on 100% it coming off of the DSP. Note that the third hamonic is so loud that I can hear in whil doing a sine sweep. You can often here the 2nd harmonic when sweeping a driver well below Fs, but I have never heard this above Fs, and never 3rd harmonic.

Bob

[ryanbouma]

Re: miniDSP users read this.

I can't help but think it's a faulty unit. I can't hear anything like distortion from mine while doing sweeps. And others have done measurements without issues to report. I should try taking some measurements.

Thanks for pointing this out.

[charlielaub]

Re: miniDSP users read this.

I am using the miniDSP-in-a-box, i.e. 2xunbalanced in, 4xunbalanced out. I am powereing off on my laptop, what I am lookking at can't possibly be due to a noisy power supply. the WTPro is also powered by the laptop. If it was a power supply problem, it would show on both. Extreme 3rd order distortion, occationally in excess on 100% it coming off of the DSP. Note that the third hamonic is so loud that I can hear in whil doing a sine sweep. You can often here the 2nd harmonic when sweeping a driver well below Fs, but I have never heard this above Fs, and never 3rd harmonic.

Bob

Do you have one of the revs with the tube output stage????

-Charlie

[devinkato]

Re: miniDSP users read this.

Bob - have you posted your results on minidsp's forum? They're semi-responsive there, and you may be able to get a replacement unit (assuming your problem is not endemic).

[dcibel]

Re: miniDSP users read this.

I was really hoping that MiniDSP could output a transfer function of the entire system, but it doesn't so it's not of much use to me. If it did give you a resulting transfer function, it would be a great tool for passive crossover design. You could try different crossover frequencies and slopes, and have a transfer function that you could design a passive filter to reproduce.

Unfortunately since it doesn't give this, its a bit of a pain to extract manually, so I never did buy one.

[Bob Brines]

Re: miniDSP users read this.

Bob - have you posted your results on minidsp's forum? They're semi-responsive there, and you may be able to get a replacement unit (assuming your problem is not endemic).

Right. I will do that tonight or tomorrow. They're in bed right now anyway.

Bob

[natehansen66]

Re: miniDSP users read this.

I notice fairly significant noise from my miniDSPs when powering from my computer, but I've never done any comparative distortion measurements. The noise is gone when powering from a dedicated supply. As others have said I would try that before writing them off entirely.

[charlielaub]

Re: miniDSP users read this.

Right. I will do that tonight or tomorrow. They're in bed right now anyway.

Bob

There is also a MiniDSP forum in the Vendors > Manufacturers forum of DIY Audio that gets responses.

-Charlie

[MSaturn]

Re: miniDSP users read this.

USB power supplies are not all built the same - it's entirely possible the miniDSP's is totally unfiltered or otherwise not isolated. Laptops put out an atrocious amount of noise from their power supplies (I can hear the hard drive spinning up through the headphones on mine.)