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Discussion Starter #1
I have a Pioneer Elite SC-65 AVR and need a known good EQ link between it and my sub amps.
Many users report voltage issues between their AVR's and MiniDSP.
Not that I'm married to MiniDSP, but it does seem like the best bang for the buck when it comes to Sub EQ that plays well with REW.

I would like to know which components have been known to work well between Pioneer Elite AVR's and MiniDSP, sans voltage issues, or output drop issues.

What say ye.:D
 

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I had the same concerns after I read some stuff about the issues on the net. This after I had already purchased an unbalanced MiniDSP 2x4. I did a check from my SC-71 sub out with a Fluke Scopemeter into a 10kΩ load and found the output to go to a little over 2 volts RMS. I set the jumper on one of the inputs to 2v and ran with it. The output of the unbalanced variant is 0.9vRMS max regardless of the input scaling. I verified that with the Fluke. I did have to increase the gain on the Dayton Audio SPA1000 plate amp it was feeding. After the first MCACC run, before the increase, the sub level set in the SC-71 was at +6.5db and the spread to the lowest sat was 13db (sat was at -6.5db). After I increased the input gain on the SPA1000 and re-ran MCACC the total spread, including the sub, was only 4db. The sub was in the middle of that spread.

I need to note that I included a Linkwitz Transform which also reduces overall output as a trade for more low end extension (worked very well) and the EQ was predominantly cuts to peaks which also reduces overall output.

Final outcome is a sub response that is nearly a full octave lower, nice house curve response from below 20hz to my x-over @ 100hz, and enough power to keep ME from cranking to reference levels. This with the 0.9vRMS output of the unbalanced variant of the 2x4 product. I'm happy, however had I done my homework I'd have ordered the balanced variant with the 2.0vRMS out.

Hope that helps.
 

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Discussion Starter #3
I had the same concerns after I read some stuff about the issues on the net. This after I had already purchased an unbalanced MiniDSP 2x4. I did a check from my SC-71 sub out with a Fluke Scopemeter into a 10kΩ load and found the output to go to a little over 2 volts RMS. I set the jumper on one of the inputs to 2v and ran with it. The output of the unbalanced variant is 0.9vRMS max regardless of the input scaling. I verified that with the Fluke. I did have to increase the gain on the Dayton Audio SPA1000 plate amp it was feeding. After the first MCACC run, before the increase, the sub level set in the SC-71 was at +6.5db and the spread to the lowest sat was 13db (sat was at -6.5db). After I increased the input gain on the SPA1000 and re-ran MCACC the total spread, including the sub, was only 4db. The sub was in the middle of that spread.

I need to note that I included a Linkwitz Transform which also reduces overall output as a trade for more low end extension (worked very well) and the EQ was predominantly cuts to peaks which also reduces overall output.

Final outcome is a sub response that is nearly a full octave lower, nice house curve response from below 20hz to my x-over @ 100hz, and enough power to keep ME from cranking to reference levels. This with the 0.9vRMS output of the unbalanced variant of the 2x4 product. I'm happy, however had I done my homework I'd have ordered the balanced variant with the 2.0vRMS out.

Hope that helps.
Oh it helps a lot! Thanks!
So, basically it sounds like the Sub out on the Pioneer Elite is sufficient to run the MiniDSP, but the output of the unbalanced MiniDSP could be better.
This would be remedied by using the balanced version of MiniDSP.
I suppose you could put a bump box between the MiniDSP and your pro amps right?
 

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Guess I could, but since there's no need ... {edit: mis-read your post's meaning - Yeah If you have pro amps and an unbalanced variant then a gain bump box would be called for}

If you get the balanced variant then you'll need to wire to the unbalanced RCA connectors correctly. It's on the forum somewhere - I've seen it. I just don't recall where and since for me there was no need ...
I believe Wayne posted the info I saw.
 

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I would like to know which components have been known to work well between Pioneer Elite AVR's and MiniDSP, sans voltage issues, or output drop issues.
Any professional-grade outboard equalizer will work with none of the issues you mentioned.


I suppose you could put a bump box between the MiniDSP and your pro amps right?
As thoroughly explained in my dissertation on gain structure (which you can find linked in my signature), a signal booster is not needed unless your receiver doesn’t put out enough voltage to drive your amplifier of choice.

Regards,
Wayne
 

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Guess I could, but since there's no need ... {edit: mis-read your post's meaning - Yeah If you have pro amps and an unbalanced variant then a gain bump box would be called for}

If you get the balanced variant then you'll need to wire to the unbalanced RCA connectors correctly. It's on the forum somewhere - I've seen it. I just don't recall where and since for me there was no need ...
I believe Wayne posted the info I saw.
I did get the balanced MiniDSP and I have many problems. My AVR has a balanced output. If I go from my balanced AVR directly to my EP 4000, all is good and gain is perfect. If I put the balanced mini DSP in the middle I have problems. The input I get on the MiniDSP is barely up from Infinity regardless of the DIP switch inside of the MiniDSP. Also the outputs of the balanced MiniDSP appear to be low as well. So, it seems like I need a bump box before and after the MiniDSP. I did get a bump box for before the MiniDSP and that did help with the input signal to the MiniDSP. But I get a very weak signal out of the other side. Unfortunately I do not have the tools to do any measuring
 

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Discussion Starter #10 (Edited)
These are the kinds of responses that prompted this thread.
What AVR are you using again Brent?
Did you wire the DSP to the AVR in the same manner (obviously a little different because of the XLR out on your AVR) as the link above?
 

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You could go to RatShack and get an inexpensive digital Multi-meter. They have one on sale for ~$35 that looks OK. http://www.radioshack.com/product/index.jsp?productId=20362256

You'll likely want something like this, too. http://www.radioshack.com/product/index.jsp?productId=11931581

Or pay a little more and get a USB scope.
http://www.amazon.com/HANTEK-6022BE-Digital-Storage-Oscilloscope/dp/B00BSQZ3MA/ref=pd_sbs_indust_1?ie=UTF8&refRID=0H88Y2ZBT4KZHE0FY47R
If you go either of these routes and you need any help just let me know.
 

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I have an IB sub and wanted to eq down to 10hz for driver protection. It's also really nice for changing things in real time. Much simpler to learn and update and also for future projects. But I have been thinking of doing exactly that with the problems I have been having, I am current just am letting Audyssey tame it and it is ok, but want more control for music.
 

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You could go to RatShack and get an inexpensive digital Multi-meter. They have one on sale for ~$35 that looks OK. http://www.radioshack.com/product/index.jsp?productId=20362256

You'll likely want something like this, too. http://www.radioshack.com/product/index.jsp?productId=11931581

Or pay a little more and get a USB scope.
http://www.amazon.com/HANTEK-6022BE-Digital-Storage-Oscilloscope/dp/B00BSQZ3MA/ref=pd_sbs_indust_1?ie=UTF8&refRID=0H88Y2ZBT4KZHE0FY47R
If you go either of these routes and you need any help just let me know.
I do have a multi meter. How would I use that?
 

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DO THIS AT YOUR OWN RISK. YOU WILL VOID ANY WARRANTY IF YOU DAMAGE AN OUTPUT DOING THIS AND DAMAGE IS A REAL RISK.

Wire a 10 kΩ resistor in the signal path of a IC cable (RCA or Balanced XLR, A cheap 5% ¼watt resistor will do fine) and use it as a dummy load on the sub out, or the output of the MiniDSP. On an RCA cut one connector off an old cable (leave it long for convenience), strip the end and solder the resistor between the internal signal wire and the shield. On the XLR solder the resistor between the wires connected to pins 2 & 3.

Be VERY careful not to allow any of the wires of the cable to come in contact with each other. Doing so will most probably fry the output under test. I use heat shrink tubing to insure this, leaving just enough bare wire to clip a lead to. Keep a watchful eye on the test probes as they are a prime source of accidental shorts - keep them separated.

Once you have the dummy load made here's the procedure to check the output.

  1. Turn power to the device you're testing off
  2. Attach the dummy load to the device.
  3. Attach clip leads to the exposed portions of the dummy load cable and to the probes of the meter. One exposed point on the cable to one probe. You've taken great care up to now to prevent shorts. Don't intentionally create one. You need to use clip leads to keep your hands free.
  4. Set the meter to read AC volts and set the range (if not an auto ranging meter) to 2 volts or greater.
  5. Apply power to the device and set the volume to minimum.
  6. Using REW or a test tone from a test CD or such, in the proper freq range, apply a signal to the device (say 50Hz for the sub out; 1kHz for a full range out).
  7. Adjust the volume up slowly. Multimeters read RMS (or a close approximation for the cheaper ones) until clipping starts to occur. After that the reading will be off. The only real way to KNOW you're clipping is with a scope.
That's about it. If you have balanced outs the reading should run up to ~2 volts. On an RCA it'll be limited to ~0.9 volts. For obvious reasons an O-scope is preferred but a multimeter will work in a pinch.

If any of this makes you nervous, or uneasy, DON"T DO IT.
 

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I did get the balanced MiniDSP and I have many problems. My AVR has a balanced output. If I go from my balanced AVR directly to my EP 4000, all is good and gain is perfect. If I put the balanced mini DSP in the middle I have problems. The input I get on the MiniDSP is barely up from Infinity regardless of the DIP switch inside of the MiniDSP. Also the outputs of the balanced MiniDSP appear to be low as well. So, it seems like I need a bump box before and after the MiniDSP. I did get a bump box for before the MiniDSP and that did help with the input signal to the MiniDSP. But I get a very weak signal out of the other side. Unfortunately I do not have the tools to do any measuring
Does the "low level out of the MiniDSP" actually manifest itself in a practical problem in your system?

Is the problem; noise from the speaker, or not being able to reach the SPL levels that you desire, or possibly something else?
 
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