Experience with using MiniDSP with their Altec?

**oface1** · March 17th, 2015, 03:25 PM

Hello everyone!

Thinking of buying this MiniDSP 2x4 | MiniDSP to use with my upcoming 604 project.

I am wondering if anyone has had any experience and what were your results and would it be worth it? I like how cheap and how you are able to tune and tweak for a lot.

Thanks!

**Kenny Brant** · March 17th, 2015, 09:52 PM

I use a 2x4 miniDSP with my GPA 416-8C's and GPA 399A's on 18 Eighteen Sound XT1464A horns. I bought the UMIK-1 Mic and downloaded the REW software from Home Theater. It works a lot like Audyssey on Home Theater Receivers. You sweep the speakers with a tone and then you load the file into the miniDSP and it equalizes everything to the room.

It is absolutely the best thing I have done to my system in a long time. It made the system so much more enjoyable to listen to.

I have used electronic crossovers and have been half way happy but went back to a passive crossover and was happy. But when I went to the miniDSP I fell in love with my system. I can have the amp I want for the woofers and the one I want for the horns. I use a 805 tube amp and a 300b amp. So 40 watts and 6 watts.

And the miniDSP doesn't take anything away. Mine doesn't hum and I have plenty of volume.

I'm sold

Kenny

**oface1** · March 18th, 2015, 03:36 PM

Kenny,

Thanks for your excellent response! I plan on initially to use the minidsp for now with a Altec 921-8a woofer and a cheap PRV Audio D280Ti driver, with some 811 horns I have laying around while I save up for a pair of GPA 604's. I am going to build some cabs that will house my initial, "getting by" system, and place the horn on top, and when the 604's get here, I'll pop out the 921's and drop in the 604's.

I will use some converted console amps I have laying around, a converted maggie console pull 6V6 for the bottom end , and a SE EL84 for the horns.

Thanks again!

**oface1** · March 18th, 2015, 05:24 PM

On further inspection, it look slike the PRV Audio D290Py-B 1" Polyimide Horn Compression Driver 8 Ohm 2/3-Bolt will be a better fit freq wise.....

**Kenny Brant** · March 18th, 2015, 08:16 PM

That sounds like a good plan. The miniDSP is so versatile you can use it with any set of speakers, even a single speaker or box system that already has a crossover built in. I thought about buying a set of GPA 604's without crossover and using the miniDSP.

You could use the same 2x4 and configure for a subwoofer or buy 2 each 2x4's for a 4 way system. And you really have a hard time beating the price and it is a bargain compared to a Behringer DCX2496, which is also a nice unit.

I have a Maggie push pull 6V6 and Maggie push pull EL84 and have had in the past a Maggie SEP EL84. All of them are fine sounding amps. I won't get rid of the two of them and wished I hadn't got rid of the SEP EL84.

I think that would be a fine sounding start and you may not go any further once you get it dialed in.

Oh, you can play around with this and that setup on the miniDSP and save your settings as a file and reload them any time you want to. The one thing I don't like is you don't know what is loaded into the miniDSP so keep track of what you last loaded into the miniDSP. You can't download the settings that are in the miniDSP, only upload. You can also change settings on the fly and immediately hear the difference.

Another thing I forgot is if you have a amp that has tubes that are too bright or a bright solid state amp it will tone it right down, not just the speakers. I have RCA clear tops in my 300b amp and they were bright sounding. After equalizing using the miniDSP it took the brightness out of the system and sounds good now.

Kenny

**wws944** · May 2nd, 2015, 05:13 PM

I just bought a Minidsp 2x4 and UMIC-1 to play around with in conjunction with my 820Cs. I will download REW as recommended above, however I was hoping to try bi-amping. Am I correct that it does not support bi-amping? The two plugins at the Minidsp site that seem to be apropos are the Two Way Advanaced (2way Advanced | MiniDSP) and Stereo Graphic EQ (Stereo Graphic EQ plug-in | MiniDSP). Which to buy? Or just get both?

Audio chain includes a linux computer -> MA-6100 preamp section -> minidsp -> MC-2100 power amp -> 820C. With bi-amping, I would also use the amp section of the MA-6100. Guessing the direct coupled MA-6100 amp would best match the HF horn, and the autoformer coupled MC-2100 would best match the LF section.

**Alien_Shore** · May 3rd, 2015, 01:11 PM

Most all active crossover applications require bi-amping. This is because the filters are active on the input signal prior to amplification. The miniDSP has a jumper that allows it to operate with or without a pre-amp, but will require bi- or multi-amping for everything except mono systems.

Oh wait, I see you're using a MC6100. Hmmm, it seems like that would be tricky to try and integrate the preamp ("direct coupled" as you say) and then the miniDSP -> amp -> LF. As Kenny says, you'll most likely have better results with your entire input signal being managed with the miniDSP, and then using two amps on the other side. But if you've got the measurement system, you can tune it in however you do it.

**wws944** · May 3rd, 2015, 09:41 PM

Originally Posted by Alien_Shore

Most all active crossover applications require bi-amping. This is because the filters are active on the input signal prior to amplification. The miniDSP has a jumper that allows it to operate with or without a pre-amp, but will require bi- or multi-amping for everything except mono systems.

Oh wait, I see you're using a MC6100. Hmmm, it seems like that would be tricky to try and integrate the preamp ("direct coupled" as you say) and then the miniDSP -> amp -> LF. As Kenny says, you'll most likely have better results with your entire input signal being managed with the miniDSP, and then using two amps on the other side. But if you've got the measurement system, you can tune it in however you do it.

The MA-6100 has separate pre-amp and power amp sections on a single chassis. There are RCA jacks on the back for preamp out and power amp in. Normally there are a pair of U-shaped jumpers between the two. Pull the jumpers and it is trivial to insert the minidsp between the two. The power amp section of the MA-6100 has the output transistors direct coupled to the output, as opposed to the MC-2100 which has autoformers in the output stage.

I got the REW software up and running. For some reason the latest v5.11 release on linux is a shar style archive, and didn't work right. I didn't have time to mess with it much, so can't make any recommendations to the REW developers yet. The older 5.0 release simply has the java .jar files in a zip archive and was not a problem. It found the UMIK-1 and can play tones and noise to the audio outputs, so that is good. Still making baby steps figuring out how to calibrate and use it.