MiniDSP - Page 42

i think what stereo is saying is, on some receivers, the voltage goes up so high the more you crank it that even that wont be enough to keep the signal from clipping in the MiniDSP

It won't do any good if the signal is already clipped (inside the MiniDSP).

The QSC pieces are quite reasonable when purchased used (and there are plenty of them out there on everybody's favorite auction site). I have 5 DSP-4's that have averaged about $150/per -- they were purchased years ago though -- your DSP-30 is a better standalone option than the DSP-3/4's as the latter are meant to plug into the Dataports on specific QSC amps, but they can be used with a power supply and connected to other brands of amps as well. The biggest limitation is they are only 2 in/2 out; whereas you can buy an 8 in/8 out MiniDsp for $399 plus whatever shipping is to the US (does anybody know what the average shipping rate is?). The QSC Basis and DSP322 8 in/8 out products are big, big bucks though, selling for around $4-4300 new. I managed to jump on a used 922DZ a few years ago that a sound company forgot to list with the correct amount of digits in the asking price...it was a Buy It Now and I clicked the button and paid, they shipped it and I never heard any complaints from them...turns out is is CobraNet specific though and I don't know for sure yet if I will be able to patch it into my system without too many additional pieces. Going to have to enlist somebody with a much bigger brain than I to figure out the answer.

I've been very tempted by the MiniDsp products, but keep hearing many industry and HT install guys say they just don't have the quality circuits/parts to handle anything above the subwoofer range without jacking up the sound.

Which specific issue? As I discovered there's more than one.

Other than the meters not reporting peak voltage, what other issue did you find?

Didn't your research show that the miniDSP's inputs and outputs clip at a voltage even higher than what the manufacturer publishes? Isn't that a good thing?

I'd love to know who you've been talking to. To me that just sounds like the typical audiophile nose in the air snobbery. You know the disdain for something simply because it doesn't have the inflated sky high pricetag needed to be taken seriously by those sorts of people.

Actually, the board quality is kind of ****. It does the job for subs though. And by kind of **** I mean components barely soldered in place or missing. At least they sent me the parts that were MISSING off of mine so I can have all the channels work.

Slap a Krell sticker on it and maybe they will like it more.

Quality parts? ....

Either they're transparent enough for mains duty or they aren't, .... it'd be easy to determine pretty quick, via a brief listen.

Lets see...

The meters don't indicate dB
The meters don't reflect peak signal levels, but something like an RMS area under the curve measurement
The RCA outputs of the balanced model have half the voltage of the XLR outputs which means RCA in to RCA out cuts the voltage in half (~6dB signal loss)
The input / output clips at voltages that can be found in the LFE signal chain of consumer gear
Yes, it's higher than the specified 2Vrms but it still isn't high enough for some use cases and requires careful measuring and attention to work around. If it clipped at 2Vrms it would be totally useless for LFE duty.

I can't say I share your assessment. I was quite impressed by the quality of the soldering work on my Balanced 2x4 unit. It looked quite good for a relatively low cost Chinese product. It looked comparable to the automotive PCBs I work with on a regular basis.

There, I fixed that for you.

I think you're taking this a little too far.

Yes, the meters have issues, but everything else you stated is clearly documented by miniDSP. Your findings in these areas are actually confirming the products capabilities, but you keeping claiming to find "issues". You have to take it easy.

My unbalanced 2x4 (rev A) can easily drive my Peavey IPR-3000 to clipping the outputs, so less than 2vrms doesn't make it useless.

I do think it's a legit concern.

I suspect it's not as much parts quality but more design approach and topology.

I ordered a new, custom Sabine 4x8 processor a month or so ago, and I'm primarily going to implement it as a subwoofer management solution. However, if it's transparent enough, I'm going to run the mains thru it as well for EQ'ing the time and freq domain.

I've no reason to think it won't be, but I'm certainly not going to take a step backward in the 60hz and above audible quality,.. so we'll see when I get it.



Somewhat akin to Reagan and Gorbachev in the 80's, ......trust but verify.

Thanks

To clarify, this was specifically regarding LCR usage.

I do totally agree with your assessment about many 'audiophools' Seth. One of the people I saw that tried out a MiniDsp and said it wasn't very good at all was Danny Richie -- I am more than a bit skeptical about some of his audio beliefs, but I do know he is capable of making some fine speakers. I've seen comments from others in the industry as well, but I cannot recall any specifics right now, and I suppose it's possible some of these guys feel threatened. I've also seen Erskine and his guys mention on more than one occasion that they have tried out the MiniDsp and found it to have many issues, but then again, I imagine they might stand to lose a few bucks by not selling QSC products if more of us want to save 4-figure money and opt for MiniDsp stuff instead.

Hell, I'm hoping they're wrong!
Edited by Aaron Smith - 12/21/12 at 9:51am

Okay so maybe not to you, but you have a pro amp with probably the lowest input voltage requirement of any.

Gotcha, and good point.

My contention being, I'll very likely decide right away,...if it's so subtle it's worthy of a blind test, then it's close enough for me.

I'm just ready for it, as my order got screwed up twice, it's been a long wait.

Well, I don't want to accuse anyone specifically since I don't know who specifically said what, but many of those same sorts of people have claimed for a long time that any EQ in the signal chain was bad. So, take that belief and toss in a relatively low cost product from China and those sorts of comments don't surprise me. Are they right? I don't know. I haven't tried it. But, I don't tend to take comments from people who can "hear" lots of other audiophoolery too seriously.

That might be true.

Also, it had no issues driving the EP4000 to clip its outputs either, and that right there, is a VERY popular amplifier in the DIY community!

Probably because we're talking test tones, not program material. A lot of things can be marginal on test tones, but utterly masked on real program material.

Remember that the box is $100 or so extra, but worth it IMO because it has all the holes punched and looks pretty good.. (For multichannel audio use, there's no reason to spring for the 10x10HD, because its extra features aren't of use here. And screwing the board to the case is a 5-minute job even for a serious klutz.)

Shipping [edit]to the US at least[/edit] is, I believe, $25 flat rate no matter what you order. At least, they charged me $25 for my last order (8x8 board, their then-new case for the 8x8 board, two balanced 2x4-in-a-boxes). That was, if memory serves, late last spring or early last summer.

And keep in mind that the case is another $100. Still, I know of nothing that's $500 new that offers 4+ inputs (LCR + LFE is the minimum required for a serious multichannel audio speaker manager, IMO), 8 outputs, Mac-compatible software, and both balanced/unbalanced I/O. Actually, I know of nothing else with that feature set period...

The people with vendettas against miniDSP are mostly just your standard audio industry con-men, such the greasy charlatan hack you mention above.

it's worth noting that Dr. Geddes, Dr. Kreskovsky, and others find the miniDSP adequate for their flagship music/HT loudspeaker designs (GedLee Abbey, the NaO and NaO Note lines, etc). After playing with mine a bit I've no qualms whatsoever about running my three front mains through it. (I have to, to blend the "flanking subs" with the mains.")

IMO, the only concern with running the miniDSP into mains is that it has a nasty turn-off thump. I think using the remote in/out will make it work just fine in normal use, but if one lives in an area that's prone to power outages (or people who like to pull cords out of the wall, etc.) then one could be going through drive-units at an undesired pace. That's why I bought a UPS for mine!
Edited by DS-21 - 12/20/12 at 5:21pm

Then the output isn't really limited to .9V since .9V won't saturate a EP4000. 1Vrms will if the EP4000 is driving into 2ohms x 2.

Thanks for the shipping info.

I wasn't aware that those two were offering MiniDsp bundled with their products, but just checked it out. That says much in my mind. It does have an amazing array of features for the money. If I can't get the QSC Basis patched into my system for a reasonable investment, I do believe I'll be going this route (maybe give them a while longer to keep refining the product and options).

I've seen a few exchanges between you and Richie.

Speaking of the thump, I had always been one to hot-swap cables, but finally was convinced it's not such a great idea after blowing up my second BASH amp in 6 months a few years back doing so (my fault, but I really don't like BASH!).

My issue with the 8x8 was that I accidentally unplugged it, with a speaker plugged into the ElectroVoice CPS-8.5 (500W/4Ω). The turn-off thump was quite powerful.

Fortunately, I was testing it with a cheap car-fi driver I didn't care about. But the thump did result in the cone resetting back about 2mm. Easy to see, because of the polepiece extension.

Definitely don't hot-swap, regardless of which processor one uses.

That's one of my complaints about my Balanced 2x4 unit as well. It has a hairy turn off thump, which is all the worse when I have to crank the amplifier gain all the way up to to accommodate the low (relatively speaking) LFE signal I'm forced to feed the MiniDSP. Right now I have it set to turn off 1 second after my amp shuts off because if it and my Crown XLS Drivecore amp lose power at the same time I get a thump. Obviously in a power failure situation my controlled power sequencing is useless. I'm thinking to add a fair amount of bulk capacitance to it to keep it running just long enough to eliminate the thump.

I've been messing with my minidsp I got yesterday night. It doesn't drive my ep4000 very well. I have the balanced and unbalanced versions (ya I bought both lol) I haven't tried the unbalanced one yet but bought it for another project anyways. I've resorted to putting the samson back in the equation for now. I messed with the jumper and have to say, I actually do agree the thing really is not very well made. Thats not to say it doesn't sound fine but one of the rca's almost was pushed in about a 1/4 inch just from pluggin in a old rca and no even a tight one lol.
I do like the setup with the PC, it's super easy to figure out, I hate the phoenix connectors, what a dumbass idea. At the very least, they could make a kit that has legit XLR's. I mean really, how freaking hard can it be... O wait it's not lol.
Well, So far it works well enough but I can't for the life of me figure out why they don't send a wall wart with the thing.
Theres more I don't like about the unit I do like. I guess it being cheap is good but from the looks of it, you get what you pay for.
I'm not sure if it's because I'm running the xlr's and the rca preouts for the L & R that may be giving me lower voltage but I don't think this will be the unit for me.

Ahh well, it was fun to try it out.

im starting to think maybe getting the unbalanced model and using a bump box such as the ART cleanboxpro to regulate the output level is the way to go.

the product minidsp supply does every thing the manual says it can do any problems u have with it that is user error, i know for a fact i can clip a ep4k with a balanced mini dsp.

they really should figure out a way to fix the atrocious turn off thump.

Yeah, it's bad. I end up leaving mine on because of this.

Turn off your amps first, guys.

Why are you powering of your DSPs? I just keep mine powered on.