Sub EQ through Receiver?

[Omzig]

Hi,

I recently purchased a miniDSP and a UMIK to run REW on my sub and try to equalize it for better performance. When I set everything up I just ran the output from my computer straight into the amp for the sub and went through the process. I ended up with a nice set of EQ settings which were fed into the miniDSP. I ran Audyssey again on my amp and sat back to listen to the improved sound.

Unfortunately it doesn't sound as good as it did before and now I'm wondering what to change for the next attempt. One thought was if it would be better to feed the signal through the receiver to include any adjustments that Audyssey did? My receiver is an older Denon unit with the first generation of Audyssey so I don't necessarily think it is doing any EQ, probably just level, crossover and distance settings. To me though it seems like this is more like what the sub is actually seeing instead of just a straight signal to its amp.

Has anyone tried this? If so, how did it go?

If this is a dead end does anyone have any suggestions on how to iterate through the measure/eq/Audyssey loop?

The speaker measures great in REW with a room peak removed but surprisingly it sounds a little more boomy. (BTW it's a 12" sealed sub from Audio Concepts called the Titan)

 

[AcuDefTechGuy]

I never have.

I just let my Denon AVP-A1 do the sub EQ via Dynamic EQ, then feed to ATI 3005 amp, then to subs.

I have absolutely no complaints.

But I'm sure there has got to be someone who has had great success with miniDSP EQ - Like Gene.

 

[lovinthehd]

Maybe you just eq'd your computer's bass response? I'd have run any test signals thru the avr for measurement/eq and after eq with minidsp I'd still run Audyssey.

 

[agarwalro]

Maybe, your ears need to adjust to better bass .

Did you rerun Audyssey setup after bringing the miniDSP into the chain?

Can you post the before and after measurements?

 

[Omzig]

Hi guys, thanks for the responses.

AcuDefTechGuy - I was hesitant to buy the miniDSP system because I'm planning on upgrading to a Marantz SR7010 when I finish my theater room later this year. I figured it would do all the EQ so I wouldn't need an outboard unit. I ended up doing it because it looks like fun!

lovingtheHD - I think I've EQ'd the sub/amp combination but I haven't done the sub/amp/receiver combination. Since I don't know how much the Audyssey is changing things I don't know how effective my first attempt is. Before I hooked the computer up to the receiver and tried it again I thought I'd shoot the question to the forum to see if anyone has tried it. It's going to take a bit of work to run it through the receiver because I don't want the signal to go to all my speakers, just the sub. Probably just pull the wires on the speakers since they're easy to access.

agarwalro - I did run Audyssey again because after the miniDSP EQ the system sounded terrible. There was almost no signal from the sub. This was one of my concerns going in because I got the standard miniDSP and not the PRO version which has a higher output voltage. I thought I might have to send it back but after running Audyssey again the level was better. I have some measurements on my computer, so I'll look around to see if I can post them. They're not very exciting from what I remember. As expected there is a modest peak below 100 Hz that the parametric EQ settings damped out nicely and gave a nice flat response afterwards. I ran one measurement and used the values REW exported to the miniDSP. It was all quite simple but I didn't really expect it to work perfectly (too easy). Now that I need to do some repeat measurements/tweaking I had this idea of running it through the receiver. This is new to me so I was hoping some of the experts here could give some feedback (pun intended) on how to iterate to the best solution.

 

[Omzig]

One thing that just came to mind is how Audyssey works. One assumption is that if you EQ the speaker then Audyssey doesn't have to. I can understand that from one perspective but another thought comes to mind.

When I EQ the speaker I do it from one position. When I run Audyssey I do it from six positions. Given the huge variability of bass responses in the room, I can see where this would cause a disconnect.

Perhaps I should EQ the speaker in the same six positions to determine the correction curve so it would be more similar to how I use Audyssey?

I've got tomorrow off, so as soon as I'm done mowing the lawn I'll have to get out my toys and play around!

 

[lovinthehd]

Assume you mean EQ the sub, rather than "speaker", prior to running Audyssey? When you say an older version of Audyssey not doing any eq, don't think that's the case. The MultEQ versions do more with subs, tho; the 2EQ version didn't do subs. http://www.audyssey.com/technologies/multeq/flavors What is your current avr?

 

[Omzig]

So I looked up and I've got a Denon AVR-688 that has Audyssey MultEQ.

I've also attached a graph that shows the before (green) and after (blue) from REW.

 

[lovinthehd]

And a post-audyssey measure?

 

[Omzig]

Well, I haven't done that yet.

I wanted to know if it was going to be worth the effort so I haven't done it yet.

I'm assuming I'll have to just feed it through an RCA input, which is a little different than when I'm running my main source which is an OPPO blue ray player coming in on a digital input.

I'm also thinking of disconnecting the other speakers so they aren't driven by the test signal. The easiest way I can think of that is just taking the wires out of the connectors on the speakers. I'm sure there's a more elegant solution but that seems like the easiest way.

 

[agarwalro]

So I looked up and I've got a Denon AVR-688 that has Audyssey MultEQ.

I've also attached a graph that shows the before (green) and after (blue) from REW.

First I was like since you did a great job bringing the green to blue results...

Well, I haven't done that yet.

I wanted to know if it was going to be worth the effort so I haven't done it yet.

I'm assuming I'll have to just feed it through an RCA input, which is a little different than when I'm running my main source which is an OPPO blue ray player coming in on a digital input.

I'm also thinking of disconnecting the other speakers so they aren't driven by the test signal. The easiest way I can think of that is just taking the wires out of the connectors on the speakers. I'm sure there's a more elegant solution but that seems like the easiest way.

Then I was since you may have to redo your efforts. No loss, thanks to the effort you're a mini DSP champ already!

Calibrate sub thusly (assumed that you have ASIO Drivers and HDMI out on PC),

1. Denon > mini DSP > Sub
2. On Denon and sub, set the crossover at its highest.
3. Contect PC to Denon via HDMI.
4. Set Denon to "Direct".
5. Disconnect all other speakers.
6. Repeat REW/MiniDSP setup.
7. Reconnect all speakers.
8. Rerun Audyssey.
9. Profit?

 

[Omzig]

That's an interesting way to hook up the computer. I wouldn't have thought of that but it makes sense.

I'm not sure what ASIO Drivers are so I'll have to Google that.

Does setting the reveiver to Direct still engage Audyssey? I use that mode when listening to CDs because I thought it took all processing out of the signal path.

Better get my earplugs warmed up 'cause it sounds like I've got a bunch of test tones to listen to.

 

[agarwalro]

Get ASIO drivers here, http://www.asio4all.com/

Tutorial to help getting REW using ASIO via HDMI working,
https://www.minidsp.com/applications/acoustic-measurements/umik-1-hdmi-on-windows

 

[Omzig]

Thanks agarwalro.

On my laptop I just thought the HDMI output was for video.

So much useful knowledge here!

 

[Omzig]

Ok, so I fiddled around a little this morning.

First off, ASIO kicked my butt. I got the driver installed, changed all the settings in REW. Hooked it up to my system though the HDMI port and hardly got any output. I messed around trying to get it to work and finally punted and hooked my computer up to an AUX input on the receiver with RCA connectors.

I set the sub crossover to 250 Hz (max available) and set the Denon to "Direct" and disconnected all my other speakers. I ran a quick test in REW and didn't see any difference in the plot.

Then for fun I took measurements in the same six locations that I calibrate Audyssey (see plot).

Overall the response seems fairly similar in all the locations, especially below 50 Hz.

Since I was in the system I tried doing a little tweak to improve my movie going experience. I added a little EQ at 19 Hz, 3 dB, Q 0.5 just to extend the bass a little. The measured difference doesn't show much but when I watched Fifth Element it was pretty good.



I feel like I've still not fully reconciled the process of getting the best out of the system, but it's not too bad for the moment.

If anyone has suggestions on how they used REW and miniDSP to optimize their systems, I'd love to read about it.