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post #2401 of 2419 Old 07-25-2014, 06:54 PM
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Quote:
Originally Posted by beastaudio View Post
alright, so I am trying to figure out how to take a single input on the open DRC and make it output to both outputs....How do you do that?
To mirror 1 input, on the main page you'll see a stereo option, l1 option, and l2 option..

Select l1 ( the middle option. And both outputs will play the same signal.)

AlSo I split my output 4 ways into 2 inukes and have had zero problems
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post #2402 of 2419 Old 07-26-2014, 09:16 AM
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Awesome! Thanks man!

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post #2403 of 2419 Old 07-29-2014, 11:32 AM
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Anyone using a voltage divider circuit to drop the input line voltage into their minidsp?

I have like ~12Vrms on my pre-outs and was gonna use 3ohms over 1ohm to cut line voltage to ~3Vrms....

Does this sound right?
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post #2404 of 2419 Old 07-29-2014, 11:40 AM
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That's unnecessary, your receiver will give the miniDSP much lower RMS voltage after level matching. Going from 12 V to 3 V is only 6 dB down, your amplifier after the miniDSP will make up for that. Your receiver will never hit those voltages under normal circumstances
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post #2405 of 2419 Old 07-29-2014, 12:15 PM
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I hope your right. I had to run my BFD in the +4dbu setting because it would still clip the input with the trims set at -12 on the AVR.

I'll see how it works as I don't really want to but if the inputs on the mini clip at 2Vrms, I don't see how I won't need to....

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post #2406 of 2419 Old 07-29-2014, 12:24 PM
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How did you measure the 12 V rms? Did you input a 0 dB signal with the receiver at 0 dB? In that scenario if the voltage is 12 V RMS, then after level matching the LFE, if it's set to say -6 dB, then the max signal the LFE pre-out will do is 3V RMS. If you want to run above reference, you can get the additional output from either additional subs/amps, or turning the gain up on the external amp. As long as the miniDSP has the output voltage to drive your sub amp, then the AVR will never be the limiting factor, the signal just has to be turned down.
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post #2407 of 2419 Old 07-29-2014, 01:03 PM
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Yes I measured 60Hz sine at 0dbfs on a multimeter to approximate rms voltage all trims maxxed and avr at "0"

I get what your saying but dont the A/D converters on the minidsp input clip at like 2.2Vrms or something crazy low?

I basically wanted to set it where the middle of the signal chain didn't clip before the amp... When doing this with just the AVR controls with the BFD I found I had to use extreme cuts to trims -12db on the related outputs to keep from clipping the inputs on the BFD. Also when using extreme cuts like this I found the dynamic range to be compressed and or the signal to be very "on-off."

Is there a problem with the attenuation circuit?

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post #2408 of 2419 Old 07-29-2014, 01:07 PM
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Using an attenuation circuit is worse than turning down the trims, because your receiver will put out more distortion with a higher voltage, and less distortion with a lower voltage. It should have zero effect on dynamic range. You should aim for - 6 dB trim, if it wants -12 dB, turn the amps down a bit.
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post #2409 of 2419 Old 07-30-2014, 06:15 PM
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What Bassment said: No reason to rig up a voltage divider when you have a sub level control that you can dial down. It’s all the same in the end, as far as getting the voltage cut you need goes. The only issue you might have is if your amp requires more than 2 volts to drive it to max. If that’s the case you’ll have to ditch the mini for a more suitable equalizer.


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Originally Posted by NicksHitachi View Post
I basically wanted to set it where the middle of the signal chain didn't clip before the amp... When doing this with just the AVR controls with the BFD I found I had to use extreme cuts to trims -12db on the related outputs to keep from clipping the inputs on the BFD.
Are you saying that with the BFD set for +4, your receiver would still drive it into clipping??

Quote:
Is there a problem with the attenuation circuit?
What attenuation circuit, the one for the receiver’s sub output?

Regards,
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post #2410 of 2419 Old Today, 12:30 AM
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What is the best way to split 1 signal to 5? How about using lots of Y-cable/splitters?
I'm thinking of building 5 mid bass modules to reproduce 80-250Hz.
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post #2411 of 2419 Old Today, 12:42 AM
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Quote:
Originally Posted by Skylinestar View Post
What is the best way to split 1 signal to 5? How about using lots of Y-cable/splitters?
I'm thinking of building 5 mid bass modules to reproduce 80-250Hz.
Splitter are fine, or you could approach Blue Jeans Cables and see if they'll do a 1-5 in the lengths you need.

The thing you need to consider is the input impedance of the amps. They will add in the same way as speaker drivers in parallel so 5@10k = 2k. Make sure the MD, or whatever you're feeding them from can handle the load.
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post #2412 of 2419 Old Today, 02:30 AM
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Originally Posted by A9X-308 View Post
Splitter are fine, or you could approach Blue Jeans Cables and see if they'll do a 1-5 in the lengths you need.

The thing you need to consider is the input impedance of the amps. They will add in the same way as speaker drivers in parallel so 5@10k = 2k. Make sure the MD, or whatever you're feeding them from can handle the load.
You mean there's a chance of damaging the amp?
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post #2413 of 2419 Old Today, 02:55 AM
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Quote:
Originally Posted by Skylinestar View Post
You mean there's a chance of damaging the amp?
I typed a long reply here, but FF crashed and I lost it and not in the mood to do it again.

Detail exactly what you're connecting to what, and the input impedance of the amplifiers you're using; use the balanced Zin if using this way, unbalanced if not.
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post #2414 of 2419 Old Today, 04:44 AM
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Quote:
Originally Posted by Wayne A. Pflughaupt View Post

Are you saying that with the BFD set for +4, your receiver would still drive it into clipping??
Yep, quite easily in fact I still ran -8-10db cuts on the sub channels with the BFD set at +4db. I don't even run my stuff at reference either, normal movie listening is in the -10 range on the AVR dial.

Quote:

What attenuation circuit, the one for the receiver’s sub output?

Regards,
Wayne A. Pflughaupt
Yes I mean the voltage divider for the sub pre out. Its all conjecture at this point since the mini doesn't have a built in input attenuator or gain before the signal goes digital. I just wanted the knowledge up front in case I need to do something.

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post #2415 of 2419 Old Today, 04:48 AM
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Originally Posted by Skylinestar View Post
You mean there's a chance of damaging the amp?
He means whatever is feeding the amp. By paralleling all those connections your dropping the impedance of the circuit. With voltage constant your current will increase inversely proportional to impedance.

V=IR

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post #2416 of 2419 Old Today, 05:36 AM
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Quote:
Originally Posted by A9X-308 View Post
I typed a long reply here, but FF crashed and I lost it and not in the mood to do it again.

Detail exactly what you're connecting to what, and the input impedance of the amplifiers you're using; use the balanced Zin if using this way, unbalanced if not.
Quote:
Originally Posted by NicksHitachi View Post
He means whatever is feeding the amp. By paralleling all those connections your dropping the impedance of the circuit. With voltage constant your current will increase inversely proportional to impedance.

V=IR
Denon 3312 AVR sub out > Antimode8033 >>>>> 3 crown XLS amps >>>>> 5 drivers
I guess it's a NO. What if minidsp in added into the chain (between antimode and amps) to split 1 to 5? will this drop the impedance too?
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post #2417 of 2419 Old Today, 06:41 AM
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No, it wont, it will take the signal in from a single XLR and instead of paralleling, it multiplies the signal via the DSP. But can I please ask about the root of this situation...What in god's name would you need 5 different MBM's for?
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post #2418 of 2419 Old Today, 06:51 AM
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Hmm what is need?

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post #2419 of 2419 Old Today, 07:29 AM
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Haha, yea, kind of the pot calling the kettle black here I guess, I was just pointing out, dual driver mbm's could be done, you want them seemingly co-located so why would a 5 way actually be needed? You could couple several drivers to a single source and not need all the separate XLR cables.

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