MiniDSP for filtering

[j.postema]

Hi everyone,

I've built a pair of electrostatic loudspeakers and I'm considering to build a sub woofer for low frequency extension. I'm still not sure what type of woofer I want to build, although I like the idea of an open baffle woofer. For quick implementation of filters I like the idea of using a digital filter. As I want to keep things inexpensive / budget, I'm interested in the MiniDSP products like the 2x4 HD or NanoDigi 2x8 (B). Even without sub woofers a digital filter could be of good use , e.g. to damp the fundamental resonance of my electrostatic loudspeakers I think.

I'm just not sure about sound quality, would a digital filter affect sound quality in a negative way? As far as I understand from reports it should not be a problem. Do you have any opinions about this idea? I'm not overly critical as I'm currently using budget gear like a Hifiberry DAC+ which I find adequate. So I don't need the best quality gear, as long as it's good I'm fine with it.

[Ali Tait]

These are a versatile and good sounding bit of kit, paticularly so given the low cost. I used the 2x4 for a couple of years or so, before moving to the 4x10 HD, which is considerably better sounding IMO, albeit at a cost. It will also give you remote volume control as a bonus.

I'd recommend the 4x10 if funds allow.

[danilo]

Hi everyone,
I'm just not sure about sound quality, would a digital filter affect sound quality in a negative way? As far as I understand from reports it should not be a problem. Do you have any opinions about this idea? I'm not overly critical as I'm currently using budget gear like a Hifiberry DAC+ which I find adequate. So I don't need the best quality gear, as long as it's good I'm fine with it.

A DSP certainly can affect SQ. Clearly audibly so.. in My ears
Which I find odd as some wax on about perceived differences in resistors... whereas I've never been able to hear differences.
Yet DSP noises go largely unmentioned.
Will it be of concern to you? Dunno..It may or may not.
Happily dsp gizmos can be quite inexpensive so not a costly experiment.. Try and see ?

[IslandPink]

What are the current choices on these ?
I've heard a lot about MiniDSP, probably because it's affordable. There's the Behringer one , what's it called ( 9624 ? ) .
I've heard some non-convincing sound from systems built around these, and although it would be great ( with my horn-based system ) I've not wanted to commit to any combination that depends on using these DSP devices, so far. Currently I'm looking at one option that DOES , though .. tentatively.
I've seen mods discussed to the Behringer to make it sound better, by guys like Gary Pimm in the 'states so I guess the stock one doesn't sound that good if you have a very transparent system.
In the London area horn-crowd ( if four or five people is a crowd ) I hear recommendations for the Nadja ( is it ? ) being a fair bit better.

Sorry, probably taking the thread off-topic but it would be interesting to hear some thoughts on where the MiniDSP sounds in terms of ranking. I'm concerned myself about how well a very good vinyl sound can get through these things, especially the HF bit.

[Ali Tait]

The 4x10 sounds considerably better than the Behringer to my ears Mark, though mine wasn't modified.

[IslandPink]

OK, that's useful .
I should really try & get down to Luton some time early this year and have a listen to Pete's system with the replica WE16a's with Najda DSP. Kill two birds with one stone so to speak - long wide-band horn with compression driver and good DSP.

[Ali Tait]

Not heard Nadja gear as yet, have read good things though.

[j.postema]

Hi, thanks for your replies and suggestions!

[j.postema]

Hi,

I'm still considering to buy a MiniDSP like the 2x4 HD but still hesitating as I'm not sure if sound quality is compromised? I've read about limited amount of taps (2042 taps per chanel at 96khz, equivalent to 1021 taps at 48khz) which would not be enough for linear crossovers. But I'm not sure if I want that right now.

At the moment I use an old Windows pc with Peace equalizer software. Would the MiniDSP 2x4 HD be much more limited in sound quality? I prefer the idea of having a compact device that is low power and dedicated. I'm planning to use my CD player as transport, connect it digitally to the MiniDSP and use the MiniDSP remote for volume control. Would that have an audible effect on sound quality? And how does sound quality of the 2x4 HD compare to the 4x10? The 4x10 being more expensive, I prefer the 2x4 HD budget option.

Thanks!

[Ali Tait]

2x4 is cheap and sounds good. The 4x10 is considerably more expensive but sounds considerably better. Take your pick. :-)

[Magna Audio]

Have a look at WAF Najda
48 / 96 / 192 capable.
It depends how DIY capable you are.
2 x 4 as standard can be extended to 2 x 5 channels.
It's the real deal SQ wise.
The built in DACs are v good.
Sound wise it was as good as, and considerably better than my favourite DAC and pre, costing many many times more, once you use the X/O, time alignment and room mode taming capabilities.

The Op amps can be upgraded using Burson discreet op amps.

[j.postema]

Is the DA-converter responsible for the lower sound quality of the 2x4 HD compared to the 4x10? Would, in that case, it be an alternative to get a nanoDIGI 2x8 B together with separate DA converters?

Another question: I would like to use the IR remote for volume control on the 2x4 HD as I will connect the digital output of my CD player, but would this affect the sound quality? (making signal smaller = less bits)

[paulf-2007]

Have a look at WAF Najda
48 / 96 / 192 capable.
It depends how DIY capable you are.
2 x 4 as standard can be extended to 2 x 5 channels.
It's the real deal SQ wise.
The built in DACs are v good.
Sound wise it was as good as, and considerably better than my favourite DAC and pre, costing many many times more, once you use the X/O, time alignment and room mode taming capabilities.

The Op amps can be upgraded using Burson discreet op amps.i find najda is very good and on par with deqx but less expensive. Although deqx does measure driver response and correct phase errors. Also room correction but I never used that. I don't have personal experience of minidsp. Anyone who claims to be able to hear any fault with dsp has my sympathies.
I am using najda as a dac at the moment but got it for speaker projects when I get time for them. It has a very good dac.

[Magna Audio]

Good DSP I agree with Paul.
Beringer 24/96 had noticeably poor SQ. The auto time alignment was fun though..

Mini DSP could be good, certainly the better one.
I was put off by all the SW plug ins, seemed an over complex sales approach. That and the location.
Najda is Europe and has 2 DIY audio threads as long as a hundred arms to read about and learn from and ask questions to.
I guess there are similar for mini DSP though?

[Ali Tait]

There is a miniDSP forum, lots of knowledge and helpful peeps.

[Qwin]

Whether you want Phono or balanced outputs (or both) may effect your decision.
miniDSP also do a plate amp with on board DSP. Meant for Sub use but would work providing the max crossover point is high enough for you, would need investigating. Hypex do something similar, which will probably be a little more expensive. Worth checking both these out as it could be a compact DSP/Amp solution.

[iansr]

Have a look at WAF Najda
48 / 96 / 192 capable.
It depends how DIY capable you are.
2 x 4 as standard can be extended to 2 x 5 channels.
It's the real deal SQ wise.
The built in DACs are v good.
Sound wise it was as good as, and considerably better than my favourite DAC and pre, costing many many times more, once you use the X/O, time alignment and room mode taming capabilities.

The Op amps can be upgraded using Burson discreet op amps.

Does it have digital outputs to allow you to use DACs of your choice?

[paulf-2007]

Does it have digital outputs to allow you to use DACs of your choice?why would you, the dac is excellent.

[iansr]

why would you, the dac is excellent.

So you've got 2 DAC options, an excellent one and one that one of the world's leading DAC designers has been developing for about 4 years to make it as good as he possibly can. Which would you want to use?

[Magna Audio]

There was much discussion about which DACs to use on the DIY audio thread at the time.
You can argue that one DAC is technically better than another till you're blue in the face.
The best sound discussion boiled down to how the DACs were implemented in the total solution.

You can change them and I've seen Najda builds with 5 standalone DACs, but that was a lot of work.

The main mod is changing the OP amps for Burson discreet jobbies.
That's just an unplug and plug in..

Najda's analogue volume control is good. There's the ability to control each sub channel independently in analogue too.
Perhaps the others can do this too?

[Ali Tait]

Yes, each input and output has it’s own level control in the miniDSP software

There are also internally switchable gain for inputs and outputs via DIP switches, so can be matched to a wide variety of system gain structures.