Just a quick question on the Toslink connection for MINIDSP 4X2HD

moves

moves

Audioholic Chief
Alrighty... I don't have a 3.5 to RCA so I just unplugged the external amp for my mains and only got a reading from the sub. The mic position was 9 inches from the centre of the woofer. This is what I got.

sub sweep #1 10 - 200Hz Mic 9 inches from cone.jpg
 
everettT

everettT

Audioholic Spartan
So that confirms the spec from dayton, roll off at 30hz
 
everettT

everettT

Audioholic Spartan
I'm gonna be on the road so I'll check the thread periodically
 
moves

moves

Audioholic Chief
I'm gonna be on the road so I'll check the thread periodically
Alrighty... thanks again. About the graph.. why are there 3 lines? 2 red and one black.
sub sweep#1 1:3 smoothing mic 9 inches from cone.jpg


Next, I guess I will try to insert the miniDSP and run some tests.

I am guessing the next step will also be to figure out the Linkwitz transform inputs from my previous post? Please let me know if you have any input on that.... not sure what to input there as the instructions on the minidsp site instructions for setting up the Linkwitz transform don't seem to be updated.

Here is the graph smoothed at 1/3
 
everettT

everettT

Audioholic Spartan
Dont insert the minidsp untill its programmed. You cant make adjustments with it connected. I'd do thru their tutorials before anything else.
 
moves

moves

Audioholic Chief
Dont insert the minidsp untill its programmed. You cant make adjustments with it connected. I'd do thru their tutorials before anything else.
Oh yea I looked through the instructions a bunch of times to make sure I don't blow anything up...

I know you don't agree with this wiring but I have channel 1 on the amp going to output 1 and channel 2 on the amp going to output 2 on the Minidsp.

Problem is now that I am only seeing a signal on channel 1... before the minidsp was connected both channels on the amp were receiving signal.
 
everettT

everettT

Audioholic Spartan
Its avr 》minidsp 》amp. Single cable to minidsp, one cable with y splitter to amp. Because your still convinced that your sub setup is correct its extremely difficult to help, as it's not orthodox, not saying it cant work, it's just hard for me to help with it.
 
moves

moves

Audioholic Chief
Its avr 》minidsp 》amp. Single cable to minidsp, one cable with y splitter to amp. Because your still convinced that your sub setup is correct its extremely difficult to help, as it's not orthodox, not saying it cant work, it's just hard for me to help with it.
ahhh y splitter from mini output one to amp. I'll try that. *EDIT* that worked... I didn't include the y splitter that was the problem.

How does that graph look above?
 
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everettT

everettT

Audioholic Spartan
ahhh y splitter from mini output one to amp. I'll try that. How does that graph look above?
Not sure of the REW settings but the roll off looks right. If it was me I'd spend time taking a bunch of measurements with REW till your comfortable. Then work on the worksheets which I'll look for mine. Since I'm still on the road it may take a day for them.
 
moves

moves

Audioholic Chief
Not sure of the REW settings but the roll off looks right. If it was me I'd spend time taking a bunch of measurements with REW till your comfortable. Then work on the worksheets which I'll look for mine. Since I'm still on the road it may take a day for them.
Awesome... no problem about the time. I appreciate it. Again, you say worksheets (plural) but all I saw was the one spreadsheet. I'll wait for your reply for when you get back.
 
moves

moves

Audioholic Chief
Alright so I got my first measurement without the minidsp connected at the main listening position. Volume was set at 75db for the Umik. crossover in the AVR is set to 200Hz. Doesn't look too bad to me but what do I know...

What would you say would be the next step? Try the linkwitz transform?

sub sweep 1 at MLP no mini connected.jpg
 
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moves

moves

Audioholic Chief
Here is another graph with minidsp inserted with only input and output gain adjustments manipulated:

Red is no mini
Blue is with mini

Sweep#2 with mini gain input 5.3 and output gain -4.0 .jpg
 
moves

moves

Audioholic Chief
So I just discovered that I was on the wrong tab. I needed to be on the LT tab. Any idea what I should be inputting for desired Q and F?

I used 0.5 for Q and 18HZ for F...
 
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moves

moves

Audioholic Chief
I've ran into another issue maybe someone can help me with.

I ran a sweep with REW and then Crown amp went into the red and clipped. It completed the sweep but the crown amp went into the red. Not sure why.... Red was at -12db and the Air was at -22db.

Also, When I turn off the Crown, the gain meters jump up to red as well before shut down... any idea what is happening?
 
moves

moves

Audioholic Chief
Not sure of the REW settings but the roll off looks right. If it was me I'd spend time taking a bunch of measurements with REW till your comfortable. Then work on the worksheets which I'll look for mine. Since I'm still on the road it may take a day for them.
So I managed to apply the LT and ran a sweep from 10 - 125 Hz. There is a large dip at around 60Hz which is not good.... How would I fix that? how does the rest look to you?

overlay.jpg
 
everettT

everettT

Audioholic Spartan
Placement would be the first option. The rest is starting to look good. After see what the 32hz peak looks like
 
moves

moves

Audioholic Chief
Plus or minus how many db is acceptable from within lets say 10 db. Are we looking at something like +-5db flatness?
 
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