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post #1141 of 1586
11/17/12 at 2:21pm
Quote:
Originally Posted by mfrey0118 View Post

OK, tks for the info, duc...question though, why would I need a separate amp if my AVR is putting out 100 watts per channel? Can I just run the 7 analog speaker wires from the AVR to the 8 x 8, and from the 8 x 8 to the speakers?

You seem to have quite a bit of confusion. You CANNOT use the AVR you have to eq the speakers. You don't have any preouts for the speakers.

You can however eq the subwoofer ONLY using the subwoofer preouts. Look at the purple connections on the back of your AVR. Those are the subwoofers preouts. Normally you would connect your subwoofer (subwoofer amplifier) to those subwoofer preouts. What you need to do is connect the subwoofer preouts to the Minidsp THEN connect the Minidsp to the subwoofer (subwoofer amplifier).
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post #1142 of 1586
11/17/12 at 3:25pm
Hi Mfrey,

To add to what LJwelr said, you can't use the miniDSP for the other seven channels at all with that particular Onkyo. Separate amps wouldn't help.

The problem is that it has no line-level outputs between the point where the audio is decoded into multi-channel and where 100 watts of audio finally exits at the speaker terminals. So there is no way to get line-level audio out of the Onkyo to feed to the miniDSP.

If you could get the decoded audio to the inputs of the miniDSP (if the AVR had pre-outs), you would then need to feed the outputs of the miniDSP to amplifiers. That is where you often need additional amplifiers, as not many AVRs have separate line-level inputs to their amps.
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post #1143 of 1586
11/17/12 at 8:24pm
I guess I should have checked to see if his AVR had MCh RCA outputs before posting my reply. My bad for the confusion.
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post #1144 of 1586
11/17/12 at 10:18pm
Quote:
Originally Posted by MarkHotchkiss View Post

Hi Mfrey,
To add to what LJwelr said, you can't use the miniDSP for the other seven channels at all with that particular Onkyo. Separate amps wouldn't help.
The problem is that it has no line-level outputs between the point where the audio is decoded into multi-channel and where 100 watts of audio finally exits at the speaker terminals. So there is no way to get line-level audio out of the Onkyo to feed to the miniDSP.
If you could get the decoded audio to the inputs of the miniDSP (if the AVR had pre-outs), you would then need to feed the outputs of the miniDSP to amplifiers. That is where you often need additional amplifiers, as not many AVRs have separate line-level inputs to their amps.

If I'm not mistaken, my 609 has RCA pre outs...but it may be for Zone 2, I'll get behind there and look again tomorrow morning...
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post #1145 of 1586
11/17/12 at 11:06pm
Quote:
Originally Posted by mfrey0118 View Post

If I'm not mistaken, my 609 has RCA pre outs...but it may be for Zone 2, I'll get behind there and look again tomorrow morning...

Looks like your AVR does not have RCA outs other than for the subs and zone 2 L/R as you have already mentioned.

http://www.us.onkyo.com/zoom.cfm?class=Receiver&m=TX-NR609#
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post #1146 of 1586
11/18/12 at 5:14am
Thanks guys, this is good beginner information and I appreciate your patience. I am very glad I went the DIY route for my sub and that I am now getting into calibration. I'll be getting the Dayton Omni mic V2 package from PE.com next.
I've already used the SPL meter I do have (that does not connect to my laptop properly, for some reason) to measure sine waves from 18-80hz and recorded the results to come up with my own little initial frequency response snapshot.




This was done with volume on AVR simply set to 50 absolute volume, with no level calibration beforehand. All measurements taken from central listening position, appx 8-10 feet from subwoofer. I think it's a good starting point for my tinkering. smile.gif
Quote:
Originally Posted by duc135 View Post

Looks like your AVR does not have RCA outs other than for the subs and zone 2 L/R as you have already mentioned.
http://www.us.onkyo.com/zoom.cfm?class=Receiver&m=TX-NR609#

So conceivably, I could go 5.1 and use Zone 2 as pre outs that go to miniDSP. What kind of amp would be recommended for my situation and current equipment?
Edited by mfrey0118 - 11/18/12 at 5:19am
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post #1147 of 1586
11/18/12 at 5:41am
Certainly get Omnimic. It's easy to use with a great deal of support from it's creator, Bill Waslo, and from the user community.
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post #1148 of 1586
11/18/12 at 8:43am
Quote:
Originally Posted by mfrey0118 View Post

So conceivably, I could go 5.1 and use Zone 2 as pre outs that go to miniDSP. What kind of amp would be recommended for my situation and current equipment?

Not sure what you are hoping to achieve with that as the zone 2 outputs will not work as an addition to your 5.1 setup as additional speakers to give a true 7.1 channel setup. It is as what the name implies; a second distinct audio zone.

If you truly insist on running your speakers through a MiniDSP this is what you will need to do:

a. Get a new receiver with MCH RCA outputs for as many speaker channels you need.
b. Get a pre-pro with as many RCA outputs for as many speaker channels you need.
c. If you want to keep your existing receiver, get a high level speaker input to low level RCA output converter for as many speaker channels you need.

All of the above options will require that you get external amplifiers with as much power as you need for as many channels you will want to run in this configuration. Any option you choose will run you over $1000 to implement at the very least for a 7 speaker setup. The MiniDSP 8x8 is $400 not including shipping and plugin. Another $500 for a smallish 7CH amplifier and add in the cost of whichever option you choose above. Amplifier choice will be dependent on your needs. If you have very efficient speakers or sit close to them, a low power amplifier will be fine. If you're speakers are not very efficient or you sit far from the speakers then you will need a higher powered amplifier which can get real expensive really quick if you can't go the pro amplifier route.
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post #1149 of 1586
11/18/12 at 12:39pm
Quote:
Originally Posted by JackNC View Post

The difference in maximum input level is the only thing I've seen/heard of.
RevA is for up to 0.9Vrms while RevB is for up to 2Vrms input level.
Here is their FAQ. Glad I checked because I had forgottensome of the detail:
In an effort to keep everybody happy, our miniDSP 2x4 kit/box comes with a switchable jumper on the input to adjust the maximum input signal.
◦Version A is meant for consumer line level signal (-10dBV) such as a PC source, Portable media players or any other sources with an output level < 0.9Vrms. The intend of this version is to have high input sensitivity for such low driving sources, hence driving the miniDSP close to the input level ADC like to be (-15dB below headroom).
◦Version B is meant for CD player line level (2Vrms), preamplifiers or any other source with higher output driving capabilities. If you intend to insert your miniDSP kit in line with such source, you better use this version otherwise overdriving of the input converters will result in saturation, aka poor sound quality.
Sounds like RevB is what you want because it can be jumpered either way
◦All miniDSP kit/box are fitted with jumpers that can easily be toggled from revA to revB.

So with my Onkyo 609 sub out should I be using .9 or 2? The FAQ only addresses "PC source, portable media players" and sources with output level < .9Vrms. So I gues that 200 mV is less than .9V correct? However, the Onkyo's maximum rated output is 2v...

From my 609 manual:
Quote:
Rated RCA Output Level and Impedance
200 mV/2.2 kΩ (REC OUT)
Maximum RCA Output Level and Impedance
2 V/2.2 kΩ (REC OUT)
Frequency Response 20 Hz - 50 kHz/+1 dB, -3

Edited by mfrey0118 - 11/18/12 at 12:48pm
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post #1150 of 1586
11/18/12 at 3:38pm
Has anyone used the remote in/out on the 2x8/8x8 board?

I was playing around with my 8x8 after the Redskins game today, and accidentally unplugged it. MASSIVE turn off noise. The amp it was connected to (ElectroVoice CPS-8.5) has a rated voltage swing of 63V into 4Ω...and now I've officially blown my first driver that wasn't a Jordan Module or JX53. Fortunately, it was a cheap car audio speaker, and not the Aurasound woofers or the JBL SUB1500s. But it has a phase plug, and the resulting surge literally changed the rest position of the cone back about 2-3mm.

Does anyone know if it still thumps like that with the remote out? I don't currently have a driver I don't care about to test, but if so then I and anyone else using these things really needs to consider keeping it on and connected to a UPS.
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post #1151 of 1586
11/18/12 at 7:37pm
Quote:
Originally Posted by duc135 View Post

Not sure what you are hoping to achieve with that as the zone 2 outputs will not work as an addition to your 5.1 setup as additional speakers to give a true 7.1 channel setup. It is as what the name implies; a second distinct audio zone.
If you truly insist on running your speakers through a MiniDSP this is what you will need to do:
a. Get a new receiver with MCH RCA outputs for as many speaker channels you need.
b. Get a pre-pro with as many RCA outputs for as many speaker channels you need.
c. If you want to keep your existing receiver, get a high level speaker input to low level RCA output converter for as many speaker channels you need.
All of the above options will require that you get external amplifiers with as much power as you need for as many channels you will want to run in this configuration. Any option you choose will run you over $1000 to implement at the very least for a 7 speaker setup. The MiniDSP 8x8 is $400 not including shipping and plugin. Another $500 for a smallish 7CH amplifier and add in the cost of whichever option you choose above. Amplifier choice will be dependent on your needs. If you have very efficient speakers or sit close to them, a low power amplifier will be fine. If you're speakers are not very efficient or you sit far from the speakers then you will need a higher powered amplifier which can get real expensive really quick if you can't go the pro amplifier route.
So out from the 609, into a miniDSP 8 channel, and then into this:

http://shop.emotiva.com/collections/amplifiers/products/upa700

And then to speakers?
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post #1152 of 1586
11/18/12 at 8:02pm
Quote:
Originally Posted by mfrey0118 View Post

So out from the 609, into a miniDSP 8 channel, and then into this:
http://shop.emotiva.com/collections/amplifiers/products/upa700
And then to speakers?

No. If you're going that route and keeping your Onkyo, you will need to put a high level speaker input to low level RCA output adapter in between your AVR speaker outputs and the MiniDSP RCA inputs. One adapter channel per speaker channel.

Not sure if that Emotiva is powerful enough for your setup since you never listed your setup. Power requirements are based on speaker sensitivity and listening distance from each speaker. I'm guessing that if your Onkyo had enough power to suit your current setup and needs then so will the Emotiva.
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post #1153 of 1586
11/18/12 at 8:02pm
Quote:
Originally Posted by mfrey0118 View Post

So out from the 609, into a miniDSP 8 channel, and then into this:
http://shop.emotiva.com/collections/amplifiers/products/upa700
And then to speakers?
No, that won't work. Your 609 doesn't have 7.1 pre-amp outputs.
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post #1154 of 1586
11/18/12 at 9:07pm
Quote:
Originally Posted by duc135 View Post

No. If you're going that route and keeping your Onkyo, you will need to put a high level speaker input to low level RCA output adapter in between your AVR speaker outputs and the MiniDSP RCA inputs. One adapter channel per speaker channel.
Not sure if that Emotiva is powerful enough for your setup since you never listed your setup. Power requirements are based on speaker sensitivity and listening distance from each speaker. I'm guessing that if your Onkyo had enough power to suit your current setup and needs then so will the Emotiva.

Oh sorry, I have all BIC DV series, DV64 towers, DV62CLRS center, DV62si surround, and DV52siB rear surround. 90db sensitivity.

This thing is addictive...my wife's already getting irritated at me for grabbing the laptop and playing with the DSP.

Now if only the miniDSP had the capability to be seen on a home network, that'd be sweet...
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post #1155 of 1586
11/19/12 at 8:48am
Quote:
Originally Posted by MarkHotchkiss View Post

Hi Mfrey,
To add to what LJwelr said, you can't use the miniDSP for the other seven channels at all with that particular Onkyo. Separate amps wouldn't help.
The problem is that it has no line-level outputs between the point where the audio is decoded into multi-channel and where 100 watts of audio finally exits at the speaker terminals. So there is no way to get line-level audio out of the Onkyo to feed to the miniDSP.
If you could get the decoded audio to the inputs of the miniDSP (if the AVR had pre-outs), you would then need to feed the outputs of the miniDSP to amplifiers. That is where you often need additional amplifiers, as not many AVRs have separate line-level inputs to their amps.

A simple voltage divider will connect a speaker level output (like on an inexpensive receiver or car head unit) to a line level input.

With a half-bridge amplifier topology 100 Ohms in series with 1K (1W) with the + line level output off the common terminal, other end of the 100 Ohm resistor on the - speaker level input, and other end of the 1K resistor on the + speaker input will provide 20dB of attenuation when you run the line level - off the - amplifier terminal. With a balanced input it'd be simplest to tie the - signal to signal ground and + to +.

You do still need separate amplifiers, which could take the form of a receiver with analog inputs.
Edited by Drew Eckhardt - 11/19/12 at 4:30pm
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post #1156 of 1586
11/19/12 at 2:17pm
OK so if the rule is cut is better than boost, and I have peaks and valleys all through my sub freqs, what's the best method? Cut overall gain to where the highest peak is at or below zero and just cut peaks less than valleys? Or do a high shelf low shelf on the first PEQ (the one before the xover that controls 2 channels) and then cut boost on the second?
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post #1157 of 1586
11/19/12 at 3:36pm
Hi Mfrey,
Quote:
Originally Posted by Drew Eckhardt View Post

Quote:
Originally Posted by MarkHotchkiss View Post

. . . you can't use the miniDSP for the other seven channels at all with that particular Onkyo.
. . . So there is no way to get line-level audio out of the Onkyo to feed to the miniDSP.
A simple voltage divider will connect a speaker level output (like on an inexpensive receiver or car head unit) to a line level input.
OK, I stand corrected. biggrin.gif

What Drew is proposing is to turn your Onkyo AVR into a pre-pro. As he points out, you would then need separate amplifiers.

It is not something that I would do, simply because I would have an aversion to having the volume control occur prior to the miniDSP. But that may be just me, as I can't see any reason it wouldn't work that way.
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post #1158 of 1586
12/2/12 at 4:27am
So what's the best method to gain match? Turn the sub gain all the way up and use the miniDSP? Use both?

I am finding the sub starts to bottom out at really low volume at certain freqs...for instance, I ran a 30hz sine wave and up to volume 62 it sounded fine, after that it made really bad distortion noises...but the weird thing is if I continued to turn up the volume on my AVR...the distortion starts at volume 63...but if I turn the gain up on the amp, it just gets louder without distorting...is this a voltage issue? It'happens with jumpers set to .9v and 2v.

Should I get the Clean Box Pro? Should I have just gotten the balanced?
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post #1159 of 1586
12/2/12 at 5:04am
What's the input and output level reported in the MiniDSP software while this is going on? If it's at 0dB you're sending a clipped input to the sub's amplifier. I would expect the effects of clipping to be more gradual though.
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post #1160 of 1586
12/2/12 at 5:12am
Digital clipping doesn't gradually increase but it very well might be frequency dependent if you have a boost at that frequency. I'm running my subs miniDSP at about 6db below maximum on the inputs. Its much cleaner sounding that way. From what I've read the miniDSP does clip at an indicated 0db input.
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post #1161 of 1586
12/2/12 at 5:27am
I'm not even getting close to clipping...even at full volume it doesn't get closer than 25% of 0db. Besides, clipping would not explain why the sine wave gets louder with no distortion when turning the amp's gain up, versus using the volume knob of the AVR...I guess best way to make sure is take the DSP out of the chain and try to repeat. I also have a standard multimeter...any way to use that to check? Could my 25ft long shielded RCA cable be part of the issue?
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post #1162 of 1586
12/2/12 at 9:16am
Quote:
Originally Posted by mfrey0118 View Post

So what's the best method to gain match? Turn the sub gain all the way up and use the miniDSP? Use both?

I am finding the sub starts to bottom out at really low volume at certain freqs...for instance, I ran a 30hz sine wave and up to volume 62 it sounded fine, after that it made really bad distortion noises...but the weird thing is if I continued to turn up the volume on my AVR...the distortion starts at volume 63...but if I turn the gain up on the amp, it just gets louder without distorting...is this a voltage issue? It'happens with jumpers set to .9v and 2v.

Should I get the Clean Box Pro? Should I have just gotten the balanced?

The main thing you want to avoid is clipping the inputs of the miniDSP, and then avoid clipping the outputs.

Maybe measure the input voltage with a 0dBFS sine wave to set input levels. For the output, you want to avoid boost that will push it into clipping.

One of those reasons is why it gets louder without the minIDSP in the chain than with the miniDSP in the chain.

As for unbalanced vs. balanced, the balanced has a lot more headroom, and when I read through their site and figured out how easy it was to add RCA inputs to it, the balanced became my unambiguous preference.
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post #1163 of 1586
12/2/12 at 6:49pm
Quote:
Originally Posted by DS-21 View Post

The main thing you want to avoid is clipping the inputs of the miniDSP, and then avoid clipping the outputs.
Maybe measure the input voltage with a 0dBFS sine wave to set input levels. For the output, you want to avoid boost that will push it into clipping.
One of those reasons is why it gets louder without the minIDSP in the chain than with the miniDSP in the chain.
As for unbalanced vs. balanced, the balanced has a lot more headroom, and when I read through their site and figured out how easy it was to add RCA inputs to it, the balanced became my unambiguous preference.
Great so did I get the wrong one??
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post #1164 of 1586
12/2/12 at 8:54pm
Quote:
Originally Posted by mfrey0118 View Post

Great so did I get the wrong one??
No idea. You haven't figured out the cause of your problem yet.
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post #1165 of 1586
12/2/12 at 9:42pm
Quote:
Originally Posted by mfrey0118 View Post

Quote:
Originally Posted by DS-21 View Post

The main thing you want to avoid is clipping the inputs of the miniDSP, and then avoid clipping the outputs.
Maybe measure the input voltage with a 0dBFS sine wave to set input levels. For the output, you want to avoid boost that will push it into clipping.
One of those reasons is why it gets louder without the minIDSP in the chain than with the miniDSP in the chain.
As for unbalanced vs. balanced, the balanced has a lot more headroom, and when I read through their site and figured out how easy it was to add RCA inputs to it, the balanced became my unambiguous preference.
Great so did I get the wrong one??

If your bottleneck is the voltage output of the miniDSP, yes. But generally one can work around that. In your case, turning the miniDSP down and the amp gain up seems like a viable option, if that fixes the problem you've observed.
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post #1166 of 1586
12/3/12 at 5:17am
Quote:
Originally Posted by Stereodude View Post

No idea. You haven't figured out the cause of your problem yet.
Aw man, there it is again, that thing...what do you call it? Oh yeah, logic!tongue.gif
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post #1167 of 1586
12/3/12 at 5:31am
Quote:
Originally Posted by mfrey0118 View Post

Great so did I get the wrong one??

Not really. I have two unbalanced miniDSPs "In A Box" that I use for my L/C/R and a balanced for the subs. They all work, you just need to be a bit more careful with the unbalanced ones. I assume you are going from an unbalanced receiver output to a unbalanced amp input, if that's the case then the differences don't amount to much if anything. Just be careful not to overload the inputs and outputs of the miniDSP which is easily done by setting levels appropriately.
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post #1168 of 1586
12/5/12 at 5:07am
Quote:
Originally Posted by DS-21 View Post

If your bottleneck is the voltage output of the miniDSP, yes. But generally one can work around that. In your case, turning the miniDSP down and the amp gain up seems like a viable option, if that fixes the problem you've observed.

Actually, I brought all gain levels on the MiniDSP back to zero and cut the amp gain back down to half and the sub now sounds much closer to normal than it did before.
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post #1169 of 1586
12/5/12 at 5:10am
Quote:
Originally Posted by mfrey0118 View Post

Actually, I brought all gain levels on the MiniDSP back to zero and cut the amp gain back down to half and the sub now sounds much closer to normal than it did before.

Keep the gain levels on the miniDSP BELOW zero. It'll help insure that it won't go into digital clipping which is really ugly.
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post #1170 of 1586
12/5/12 at 5:49am
Quote:
Originally Posted by Theresa View Post

Keep the gain levels on the miniDSP BELOW zero. It'll help insure that it won't go into digital clipping which is really ugly.
Hmm...having it below zero was the cause of my problems...perhaps I had it too far below zero? I think I had it set at like -15db on the output (with sub amp gain all the way up) and 0 on the input. What do you have yours set at, Theresa?
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