Modulus-86 build thread

The MiniDSP 4x10HD is fine. There's room for improvement, but it's really not bad. Especially for the price! You can see my measurements of it here: MiniDSP 4x10 HD Performance Measurements.

Tom

The opendrc-an I used was so bad I could hear the noise on a compression driver 40 feet away even with it padded down 12db. The amp was providing 26db of gain. The distortion measurements were not pretty either. I have a non HD 4x10 behind me I should measure that I took out of use. It was running subs, and wasn't so great at that job either. I feel like using MiniDSP stuff with one of these amps would be a bit of a waste.

I'm now using usb audio interfaces (rme ufx+ and motu 8a) hooked up to a mini pc running brutefir for processing/xover duties.

0.000025% THD and 0.0002% THD+N at 1khz at it's best.

https://i.imgur.com/9uFmAM3.png
https://i.imgur.com/deQZNoX.png
 
I feel like using MiniDSP stuff with one of these amps would be a bit of a waste.

I do agree that I wish MiniDSP had a better performing unit. That said, there aren't many alternatives out there. The Hypex DLCP is the only circuit I'm aware of where your odds of getting something that's better than MiniDSP are reasonable. I haven't seen the measurements of the DLCP, but I can't imagine Bruno releasing a mediocre product. I also haven't looked an any of the tradeoffs made in the DLCP. I'm sure they're there. :)

Tom
 
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shrug. If put a 26dB gain amplifier off a miniDSP into a compression driver with no analog volume control you get what you deserve IMO. But that's just me :) Jan Didden did a nice analog volume board for the Behringer DCX2496 but its a bit pricey as a kit.

Dunno about the smaller units but I can change the ADC and DACs on the 4x10HD as funds, time, bovvered allow. Upgrade path and angst over which bits to chose. WNTL :D
 
shrug. If put a 26dB gain amplifier off a miniDSP into a compression driver with no analog volume control you get what you deserve IMO. But that's just me :) Jan Didden did a nice analog volume board for the Behringer DCX2496 but its a bit pricey as a kit.

Dunno about the smaller units but I can change the ADC and DACs on the 4x10HD as funds, time, bovvered allow. Upgrade path and angst over which bits to chose. WNTL :D

Or you can just get a decent audio interface and hook it up to a linux device and run brutefir ;) Not as plug and play as a minidsp, but quite powerful. I grabbed a Motu 8a for like $500 from ebay recently when I needed more IO than my UFX+ had. I would have just used a 16a for everything, but there's some hf noise or dc offset issues or something on the motu outputs (all latest gen stuff) that doesn't play nice with ncore. That said, they work just fine with the neurochrome amps I've had hooked up. I know of some using an rpi3 to run brutefir with success. Anyway, there are a handful of clean and low noise audio interfaces that work with linux.
 
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There are many ways to skin the DSP crossover cat, but a linux box sadly doesn't fit my use case. Nothing really does, but MiniDSP comes close and, as the measurements show, if you use it the right way the noise floor is nothing to worry about. And as I said, you can upgrade to better DACs.
 
I try to select 105 ºC electrolytics when I can, mostly because some people perceive them as higher quality, but also because it buys some peace of mind. In reality, the temperature rating of the cap matters little as the caps will operate near room temperature for the vast majority of their lifespan.

They tend to have better specs but 85° are definitely not a deal breaker :)
oh and I'm at page 60, just 300+ to go :D
 
Or you can just get a decent audio interface and hook it up to a linux device and run brutefir ;)

Linux. Changing the world one configuration file at a time. :D Sorry. I couldn't resist. Last I ran linux, it severely tested my patience.

Now, regarding the point you're making: Yep. An old laptop running some DSP software is a valid approach. I've used Reaper with reaEQ in the past. that worked pretty well, though the learning curve is a bit steeper than that of a "boxed" solution.

Tom