MWM DSP amplifier

[Las4444]

Hello, 

 

New to the forum and have been spending a lot of time researching my MWM build.  I have it completed my single MWM and using the K33 woofer.  I did a quick test run from a Heresy subwoofer crosser to confirmed it simply worked.  It is my understanding the heresy 1 crossover is around 800hz which is too high for the MWM.  I'm seeking help in finding a reasonably priced DSP.  So far all I came up with is the Crown XLS 1002 which gives you high, low, and band pass filters.  The manual does not give the actual crossover frequencies.  My target is 45hz ~ 600hz. 

This is just a play project in the basement but sometimes I like loud music. 

 

 

Thanks

[garyeanderson]

The MWM will roll off nearer to 500 (possibly lower), I'm a heathen and just let my center roll off on it's own. I Only use one of the Heresy speakers in the photo, and is used in the center channel, Volume is set lower than the MWM. The other Heresy and the H700's are just there as storage space is always tight. I sure some one will be along to answer your question that is better informed than me, I am just in this hobby for fun of it...

 

Gary 

 

[Woofers and Tweeters]

16 minutes ago, garyeanderson said:

 

 

Gary,

It looks like the right side of your picture is upside down. 

 

 

[Chris A]

On 3/31/2021 at 12:44 PM, Las4444 said:

I'm seeking help in finding a reasonably priced DSP.  So far all I came up with is the Crown XLS 1002 which gives you high, low, and band pass filters.  The manual does not give the actual crossover frequencies.  My target is 45hz ~ 600hz. 

DSP amplifiers can cross anywhere between 20 Hz and 20 kHz...you pick with your favorite crossover filter slopes. They also perform EQ (parametric EQ filters or "PEQs"), and provide channel delay to time align drivers.  Here are a couple of threads that might help you dial in your DSP amplifier settings (although the DSP used in the thread is Xilica, it applies equally to DSP amplifiers):

 

 

 

I recommend looking at a miniDSP 2x4 HD (two-way), or a 4x10 HD (4-way) DSP crossover.  Their performance is very good and the price is about as low as you're going to find that's hi-fi.

 

The MWM really doesn't go up to 600 Hz very well.  Below is a screenshot from user mark1101 that posted the response of his four-way setup that uses MWMs.  I circled the MWM response in red--which shows a roll-off above ~200 Hz (vertical major divisions at 10 dB--not 5 dB--so the in-axis SPL roll-off is pretty extreme above 250 and 400 Hz).  They look like they really like to cross at something like 250 Hz:

 

 

The next device that takes over (pinkish trace) at midbass and midrange frequencies is I think a KPT-305-MB or its predecessor--the KPT-XII-MB module.

 

Chris

[Marvel]

Still waiting to pick up a umik to test with REW, but I'm still crossing at 400 hz to the MWMs. Doesn't sound like a hole in the upper bass, but our ears can be deceptive. I should at least play some test tones or do some sweeps to see what my ears think of it.

 

You could also build or find some Peavey MB-1 midbass cabs for cheap. I think the have a 10-12 inch woofer in them. I believe Claude used them with his early stacks.

[garyeanderson]

22 hours ago, Woofers and Tweeters said:

 

The Belle's are stacked inverted on ported Peavey MB-1 cabinets (currently loaded with EVM15's),   I have too much stuff so some sacrifices are made.  

 

Gary

[Marvel]

21 minutes ago, garyeanderson said:

The Belle's are stacked inverted on ported Peavey MB-1 cabinets (currently loaded with EVM15's),   I have too much stuff so some sacrifices are made.  

 

Gary

 

I didn't think the MB-1s used that large a woofer.

 

Gary, a bit off topic, but did you ever get your car finished?

[Las4444]

I picked up the Crown XLS 1002 and it seems to work fine. It was easy to get from my local guitar center.    It gives fairly reasonable graduated adjustments on the crossover.  Since my speakers setup plays out of the corner I tipped the MWM on end with the mouth facing the corner and used the corner as a "horn" extension.  Since the basement walls are pored concrete the bass response is tight.  I ended up at 145hz on the crossover which filled in the bass nicely in my cavernous basement.   Between 1.5 watts on the Heresy, ~3 watts on the MWM and the two 12" subs set at 80hz it will give a good thump in the chest.  Thanks for the input and response curves.