New miniDSP 2x8 / 4x10 card

Tyson · « **Reply #40 on:** 8 Jun 2011, 10:39 pm »

Quote from: JohnR on 8 Jun 2011, 11:41 am

Please let us know how you go! I think amp quality is a bit less critical in an active system as they're covering a more limited frequency range. Just an impression so far.

It also gives you the chance to use tube amps and have them absolutely SING with the much-easier load that active speakers present, at least in the mids and highs.

pelliott321 · « **Reply #41 on:** 9 Jun 2011, 02:09 pm »

ok thanks it was just a thought Two 100k loads with a 50k load so thats around 25k is still more than ten times the preamps output impedance

Tyson · « **Reply #42 on:** 10 Jun 2011, 04:38 am »

Hey John, does the 4x10 have an auto-align feature like the DCX does? http://redspade-audio.blogspot.com/2010/12/time-alignment-with-behringer-dcx.html

JohnR · « **Reply #43 on:** 10 Jun 2011, 05:31 am »

Nope. I measure and adjust manually.

I do find the 20 ms delay curious though. Are you getting those kinds of numbers?

Tyson · « **Reply #44 on:** 10 Jun 2011, 06:11 am »

4.3ms and 4.5ms delay on the mids and tweeters, respectively. But, it did invert my mids, so that adds a bit to them.

Since my crossover is at 1.5khz, I changed the mids from "Inverted" back to "normal" phase, and simply added in an additional 1.5ms delay, so now my mids are 6.1ms delay. It's late so I can't break out the mic and measure, but the calculations should be pretty close. From a purely subjective perspective, the mids sound better with the "normal" setting and just manually adding in the additional delay.

pelliott321 · « **Reply #45 on:** 24 Jun 2011, 01:53 pm »

Just got my 2X8 board yesterday.
Now the fun begins!
I have stereo subs and 3way Maggy 3's that have been rebuilt into a hardwood frame. Right now I am bi-amping using a 3 way passive xover I built with premium parts from a circuit posted on MUG.
So first off is a new amp rack to hold a third stereo amp and the 2X8 and a case for the 2x8.
I am starting to plot out the 2X8 xover points in the app. Boy too many choices! Where to start.
The original passive xover was 12db/oct

So I guess I will start with copying this. But my question is why not use the steepest slopes? Since this is in the digital domain there are no extra components to muck up the sound.

JohnR · « **Reply #46 on:** 29 Jun 2011, 01:19 am »

Yep, you should at least try 48 dB/octave slopes. They're easy to work with.

The miniDSP 8-in 8-out is on their website, due in July it says:

http://www.minidsp.com/products/minidspkits/8-x-in-8-x-out

I'm not going to get one (have to finish this project first for sure!

) but it would fun to do an HT system with it.

pelliott321 · « **Reply #47 on:** 29 Jun 2011, 04:45 pm »

48db/oct linkwitz or butterworth.
the only difference I see is there is a sharper shoulder on the linkwitz

JohnR · « **Reply #48 on:** 30 Jun 2011, 01:48 am »

I usually use the linkwitz-riley crossover, except at low frequencies where I use whatever gives the best response.

pelliott321 · « **Reply #49 on:** 30 Jun 2011, 12:12 pm »

I am pretty excited about giving this a try
It will be another week before I get it together. I have been sick all this week and just did not feel well enough to build.

pelliott321 · « **Reply #50 on:** 18 Jul 2011, 01:45 pm »

well I finally got around to loading software on my systems laptop, mounter the miniDSP 2x8 on a board, powered it up and......nothing DOA....bummer
I am working with the supplier for a solution

JohnR · « **Reply #51 on:** 18 Jul 2011, 02:22 pm »

What power supply did you use? Also, you confirmed correct polarity?

jtwrace · « **Reply #52 on:** 18 Jul 2011, 06:03 pm »

Does the miniDSP have phase invert?

JohnR · « **Reply #53 on:** 19 Jul 2011, 12:59 am »

Quote from: jtwrace on 18 Jul 2011, 06:03 pm

Does the miniDSP have phase invert?

Yes... not sure if your question is related to the previous issue with the power supply

jtwrace · « **Reply #54 on:** 19 Jul 2011, 01:05 am »

Quote from: JohnR on 19 Jul 2011, 12:59 am

Yes... not sure if your question is related to the previous issue with the power supply

Oh no. Phase as in output phase on each output channel.

JohnR · « **Reply #55 on:** 19 Jul 2011, 01:29 am »

Sure.

Or for the 2x8:

jtwrace · « **Reply #56 on:** 19 Jul 2011, 01:36 am »

Damn. That's a really nice interface.

If they come out with one in an enclosure, I might just have to try it.

JohnR · « **Reply #57 on:** 19 Jul 2011, 02:10 am »

I don't know why they don't make the plugin free for download, they'd probably sell a lot more boards that way. You could always ask them if you wanted to try it I suppose.

pelliott321 · « **Reply #58 on:** 19 Jul 2011, 01:28 pm »

JohnR

I used both at 12v SLA and a 12vdc/2a wall wart. (not at same time)
no LED lit, laptop did not recognize usb input.
I e-mailed the supplier about the possibility of hooking up the PS with reverse polarity and he told me the board is protected from that and there is no possibility of damage from that type of mistake.

pelliott321 · « **Reply #59 on:** 20 Jul 2011, 12:13 pm »

I heard from miniDSP and I am sending the unit back for repair or replacement