Adding a third sub and possibly using two minidsp's

[willy65000]

Hello

I'm currently using a flex8 to run a 4 way activate system. Six of the output channels are for the tweeters, midranges and woofers. The other two output channels are for a svs sb1000 pro and an sb2000. The sb2000 is in the middle of the back wall and the 1000 pro is in the middle of the front wall. I have another Sb1000 pro on its way. I will not be able to individually time align the third sub as all output channels are currently being used so the plan was to run both sb 1000's off the same channel and place them side by side in the middle of the front wall where the single one currently sits. I also have a 2×4 hd that's not being used. I could run that off of one of the current subwoofer outputs on the flex but this would obviously be analog instead of digital. I haven't heard good things about the analog inputs on 2×4 hd's. So my question is would option 1 or 2 be better?

Thanks
Bill

 

[staticV3]

How are you feeding the Flex8?

If via SPDIF, could you split the signal and feed it into both miniDSPs, therefore adding four DSP channels without additional D->A conversions?

 

[willy65000]

I'm using the toss link input for tv and and the usb input for music coming from my pc.

 

[MAB]

Hello

I'm currently using a flex8 to run a 4 way activate system. Six of the output channels are for the tweeters, midranges and woofers. The other two output channels are for a svs sb1000 pro and an sb2000. The sb2000 is in the middle of the back wall and the 1000 pro is in the middle of the front wall. I have another Sb1000 pro on its way. I will not be able to individually time align the third sub as all output channels are currently being used so the plan was to run both sb 1000's off the same channel and place them side by side in the middle of the front wall where the single one currently sits. I also have a 2×4 hd that's not being used. I could run that off of one of the current subwoofer outputs on the flex but this would obviously be analog instead of digital. I haven't heard good things about the analog inputs on 2×4 hd's. So my question is would option 1 or 2 be better?

Thanks
Bill

The 2x4HD was tested here, including the ADC.
The performance of the analog inputs is indeed worse than the digital.

Analog second HD at -93dB, third HD at -100dB is so far below audibility, especially in bass where even the best subwoofer has >>1% distortion. The slight elevation in noise floor is not audible. This is pretty good performance, likely much better than the amplifier and DSP in the SVS subs, and way better than the subwoofer, for example your SVS SB-2000 Pro.

Frequency response of the 2x4HD is great with the analog inputs:

I don't see any problem using the 2x4HD as a dedicated bass crossover / PEQ using the analog input.

 

[willy65000]

Good to know and thank you. Will the dedicated bass crossover ad latency of it's own? Maybe this won't matter if it does because ill be taking measurements with that latency in place and mso or what ever i use will compensate for that? I'm not even sure that last question makes sense so oppology if it doesn't.

 

[MAB]

Good to know and thank you. Will the dedicated bass crossover ad latency of it's own? Maybe this won't matter if it does because ill be taking measurements with that latency in place and mso or what ever i use will compensate for that? I'm not even sure that last question makes sense so oppology if it doesn't.

Everything has some latency. This will be accounted for when you align the subs.

 

[willy65000]

Thank you. I appreciate it!

 

[10PSPMemSticksForMiku2007]

Don't the svs subs have their own DSP built in? You should be able to use those for delay.

 

[willy65000]

There's variable phase which is 0 to 180 degrees. Multi sub optimizer will give a number in milliseconds that needs to be entered into the dsp. Not saying there isn't a way to make it work but i honestly couldn't say. Also, there's only 3 peq filters for each sub.

 

[10PSPMemSticksForMiku2007]

I assumed there must be a delay either in distance or in ms. Not having that is just incredibly bizarre. Guess I've learned something new today.

 

[willy65000]

Ok so I've got the 2x4 hd hooked up using one of the outputs from the flex 8 and everything is functioning well. The minidsp software allows me to simply toggle between the two units which is nice. I initially wasn't sure if i would need separate software for each unit. Anyway, as i said it works fine except for when i try to take measurements. When i try to measure there's suddenly no output from any of the three subwoofers. Not sure how to solve this. Any ideas?

 

[Keith_W]

1. Draw a diagram showing how you connected your speakers/subs to your MiniDSP's. From reading your previous posts I think I have a vague idea what you've done, but it would be good to confirm it.

2. When you fire up REW, does it see one MiniDSP device or two?

3. When you use your MiniDSP control panel, does it let you use both MiniDSP's at the same time, or only one at a time?

 

[Devnull]

If the 2 1000s are next to each other just run the same eq and delay on them both

 

[willy65000]

They were next to each other temporarily. I want to run mso in order to take full advantage of having 3 subs placed in different locations. The second dsp was just sitting on a shelf collecting dust and i know i can utilize it for this purpose as others have done.

 

[thcdru2k]

Take measurements with USB disconnected from both miniDSPs and the miniDSP control software closed.
After you finish a round of measurements, reconnect USB to make filter and delay changes, then unplug USB again before the next sweep.

 

[willy65000]

Thanks to all who replied to my thread. The solution was quite simple. I had the ir remote sensor on the 2X4hd covered with blue painters tape which was not sufficient. When making adjustments to the flex with the remote the settings on the 2X4 settings were changing as well. I switched to black electrical tape and the problem has been solved. Now I'll move on to importing the 9 measurements into MSO and configuring and running MSO.

 

[willy65000]

I have a question about subwoofer outputs in my setup. I am currently using two of the output channels from the flex 8 to the two 2X4 hd input channels. Will this provide more gain than simply using one cable for connecting the subwoofer crossover?

 

[staticV3]

I have a question about subwoofer outputs in my setup. I am currently using two of the output channels from the flex 8 to the two 2X4 hd input channels. Will this provide more gain than simply using one cable for connecting the subwoofer crossover?

No. Using a single cable between Flex and 2x4 will work just as well for this purpose.

 

[willy65000]

Thank you.