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post #1 of 40 Old 05-31-2012, 05:58 PM - Thread Starter
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Hi All

Just wanted to post this question to people that use Digital Signal Processors (eg QSC DSP 30 etc ) why have they chosen those units over room correction?

I was told Digital Signal Processors give you more an idea whats going on ( which i believe is correct ) compared to room correction which gives you no indication whats going on but as some said the resolution is so much better giving you better results.

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post #2 of 40 Old 05-31-2012, 07:15 PM
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Well, I cannot speak well to DSP units. The one you mentioned seems limited to two channels. My system in the family room is 5.1 and in the home theatre is 7.1. In both rooms I needed an integrated solution dealing with the full soundfield. So I opted for room correction. My experience, at least with room correction, is that it always seemed to create a noteworthy improvement in the overall audio output for music and movies. My one experience with a high end DSP unit is that it did a very good job of flattening the phase and frequency response traits of the room at the expense of the "musicality" of the sound I heard.
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post #3 of 40 Old 05-31-2012, 07:22 PM
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I am not sure about the specific channels that the OP is asking about correcting, but I have the same question with regards to subwoofer optimization. Is there any reason, other than number of discrete subs that can be calibrated, to choose a DSP like the QSC over a quality room correction system that can correct many discrete subs , like DIRAC or Trinnov?


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post #4 of 40 Old 05-31-2012, 07:32 PM - Thread Starter
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Quote:
Originally Posted by hifiaudio2 View Post

I am not sure about the specific channels that the OP is asking about correcting, but I have the same question with regards to subwoofer optimization. Is there any reason, other than number of discrete subs that can be calibrated, to choose a DSP like the QSC over a quality room correction system that can correct many discrete subs , like DIRAC or Trinnov?

Just a general question I'm asking why members have chosen parametic eq vs auto room correction. For me I just need to further tweak my subwoofers and deciding whether to upgrade my pre amp to XT32 or go the DSP 30 route calling my calibrator to help tweak it.

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post #5 of 40 Old 05-31-2012, 07:38 PM
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If just for subs, call the calibrator. A full-blown room correction system can be very good; but you should really have pretty accurate measurement equipment to verify (depending on the system). As laborious as it may be; a read through my Datasat/ADA Trinnov thread can give some details regarding the room correction route.

Again, I'd say just use the DSP for your subs and be done.

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post #6 of 40 Old 05-31-2012, 07:42 PM - Thread Starter
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Originally Posted by DanFrancis View Post

If just for subs, call the calibrator. A full-blown room correction system can be very good; but you should really have pretty accurate measurement equipment to verify (depending on the system). As laborious as it may be; a read through my Datasat/ADA Trinnov thread can give some details regarding the room correction route.

Again, I'd say just use the DSP for your subs and be done.

Dan

Thank you Dan.

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post #7 of 40 Old 05-31-2012, 07:43 PM
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Is it likely that typical enthusiasts can utilize products like the DSP-30 correctly with nothing more than something like Omnimic or XTZ to run measurements and correct with the DSP?

I dont have a calibrator and I cringe at the likely price of flying in a well respected one that I feel will do the job 100% correctly.

Obviously the price of Trinnov or Dirac enabled equipment isnt cheap either... somehow seems easier to swallow to me though than paying for someone's plane tickets... may just have to get over that, though.

If one buys two DSP-30 units, does that give enough sub channels to configure each as one of the two outputs from an Audyssey Pro preamp like the Integra 80.2? So set phase , delay, etc with the QSC so the Audyssey can accurately see each pair of non equidistant subs as one and then let it finish the calibration? (4 subs total in my example)


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post #8 of 40 Old 05-31-2012, 08:13 PM - Thread Starter
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Quote:
Originally Posted by hifiaudio2 View Post

Is it likely that typical enthusiasts can utilize products like the DSP-30 correctly with nothing more than something like Omnimic or XTZ to run measurements and correct with the DSP?

I dont have a calibrator and I cringe at the likely price of flying in a well respected one that I feel will do the job 100% correctly.

Obviously the price of Trinnov or Dirac enabled equipment isnt cheap either... somehow seems easier to swallow to me though than paying for someone's plane tickets... may just have to get over that, though.

If one buys two DSP-30 units, does that give enough sub channels to configure each as one of the two outputs from an Audyssey Pro preamp like the Integra 80.2? So set phase , delay, etc with the QSC so the Audyssey can accurately see each pair of non equidistant subs as one and then let it finish the calibration? (4 subs total in my example)

Does the Integra 80.2 have XT32?

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post #9 of 40 Old 05-31-2012, 08:26 PM
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Yes.


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post #10 of 40 Old 05-31-2012, 08:44 PM - Thread Starter
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Yes.

How do you find that works for you?

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post #11 of 40 Old 06-01-2012, 09:06 AM
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IMO (and obviously I would say this because I am a do AV design / calibration for my day job) you can get better results from 'hand dialed' EQ than you can from an automated room correction algorithm, especially Audyssey.

Audyssey, like many other 'room correction' algorithms, does a full spectrum EQ. That is that it corrects from 20Hz to 20kHz. This is where the issues start to arise, especially in the context of a high end system or one with high end aspirations. Above about 250Hz or so the measured frequency response at the listening position is dominated by the speaker performance, and in particular their off axis performance. Audyssey measures this response at the listening position and attempts to correct it to a flat line or an arbitrary curve. In general this results in over exaggerated high frequencies and an uncomfortable sound balance because if Audyssey sees a 3dB dip at 10kHz it's going to put in a filter to counterbalance that. That filter will increase the SPL at the listening position at 10kHz by 3dB but it means that if you measured your speakers nearfield they would now be well out of whack, with likely a much greater correction filter applied. Many of you have likely experienced these 'exaggerated highs' with Audyssey!

I do think Audyssey has it's place, which is for the mass market receivers where the product is going into a mixed use room which will never see any room treatment. For high end systems though I believe better results will be achieved by a combination of hand dialed EQ and room treatment. If you look at what the top theater designers / calibrators are doing then they are all doing this. Note that some of the very advanced room correction systems like Trinnov and ARCOS are ok since they allow the calibrator to do a lot of manual adjustment and are not just 'one size fits all' algorithms.

The other issue with Audyssey and other similar algorithms in the subwoofer range is that they do not take enough variables into account. They only look at the frequency curve when developing their EQ. Although the room's response is mostly minimum phase and can be EQd <250Hz there are areas where the response is not minimum phase due to speaker boundary interference. There areas cannot be EQd, yet Audyssey tries to do it. Also I believe that to do a really good calibration job on the low frequencies you should also be looking at time decay, not just frequency response. That is something a calibrator can look at but no other system to my knowledge with the exception of Meridian's room correction algorithm looks at.

I recently did a remote calibration (yes the calibrator does not have to be physically onsite anymore, now that we have Skype and ability to send / analyze room acoustic measurement files over the internet) where we were trying to remove Audyssey XT32 from a system because although it was doing an OK job with the bass it was messing up the mid and high frequencies. I have some cool graphs from XTZ that show what we were able to achieve in the bass from manual EQ vs automated XT32, and the manual EQ results were better, especially in terms of decay. I have to say the new generation of Audyssey, XT32, is way better than it used to be at EQing the bass but still not as good as a knowledgeable person with a parametric EQ. And obviously it messes up the mids and highs, which are better dealt with through either choosing better speakers or appropriately treating the room.
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post #12 of 40 Old 06-01-2012, 10:20 AM - Thread Starter
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Quote:
Originally Posted by Nyal Mellor View Post

IMO (and obviously I would say this because I am a do AV design / calibration for my day job) you can get better results from 'hand dialed' EQ than you can from an automated room correction algorithm, especially Audyssey.

Audyssey, like many other 'room correction' algorithms, does a full spectrum EQ. That is that it corrects from 20Hz to 20kHz. This is where the issues start to arise, especially in the context of a high end system or one with high end aspirations. Above about 250Hz or so the measured frequency response at the listening position is dominated by the speaker performance, and in particular their off axis performance. Audyssey measures this response at the listening position and attempts to correct it to a flat line or an arbitrary curve. In general this results in over exaggerated high frequencies and an uncomfortable sound balance because if Audyssey sees a 3dB dip at 10kHz it's going to put in a filter to counterbalance that. That filter will increase the SPL at the listening position at 10kHz by 3dB but it means that if you measured your speakers nearfield they would now be well out of whack, with likely a much greater correction filter applied. Many of you have likely experienced these 'exaggerated highs' with Audyssey!

I do think Audyssey has it's place, which is for the mass market receivers where the product is going into a mixed use room which will never see any room treatment. For high end systems though I believe better results will be achieved by a combination of hand dialed EQ and room treatment. If you look at what the top theater designers / calibrators are doing then they are all doing this. Note that some of the very advanced room correction systems like Trinnov and ARCOS are ok since they allow the calibrator to do a lot of manual adjustment and are not just 'one size fits all' algorithms.

The other issue with Audyssey and other similar algorithms in the subwoofer range is that they do not take enough variables into account. They only look at the frequency curve when developing their EQ. Although the room's response is mostly minimum phase and can be EQd <250Hz there are areas where the response is not minimum phase due to speaker boundary interference. There areas cannot be EQd, yet Audyssey tries to do it. Also I believe that to do a really good calibration job on the low frequencies you should also be looking at time decay, not just frequency response. That is something a calibrator can look at but no other system to my knowledge with the exception of Meridian's room correction algorithm looks at.

I recently did a remote calibration (yes the calibrator does not have to be physically onsite anymore, now that we have Skype and ability to send / analyze room acoustic measurement files over the internet) where we were trying to remove Audyssey XT32 from a system because although it was doing an OK job with the bass it was messing up the mid and high frequencies. I have some cool graphs from XTZ that show what we were able to achieve in the bass from manual EQ vs automated XT32, and the manual EQ results were better, especially in terms of decay. I have to say the new generation of Audyssey, XT32, is way better than it used to be at EQing the bass but still not as good as a knowledgeable person with a parametric EQ. And obviously it messes up the mids and highs, which are better dealt with through either choosing better speakers or appropriately treating the room.

Thank you Nyal Mellor this is the kind of post i was looking for. I've read alot of positives for audyssey and not much on parametic eq. Its good to read a different opinion regarding audyssey.

Thank you for your time.

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post #13 of 40 Old 06-01-2012, 10:51 AM
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I probably do not have a good answer, but I am aware some very reputable individuals like Ersknine and Mark Seaton are using DSPs instead of room correction when they work. When I asked Dennis once, his answer was basically he was not happy with the results of a room correction system like Audyssey. I believe it does not provide the necessary flexibility required as opposed to DSPs.
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post #14 of 40 Old 06-01-2012, 10:59 AM
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My experience with Audyssey (although I haven't used X32) is in line with Dennis Erskine. My experience with Trinnov is it is a different animal all together. At least in my room and I had an Erskine person do my initial set-up with QSC before trying Trinnov. Just my opinion although I think you can find some pretty saavy guys in the LA area such as Sanjay that would echo that.

P.S. Currently using the QSC (Erskine group) for equalizing three subs before input into Trinnov.
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post #15 of 40 Old 06-01-2012, 11:38 AM
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Great post Nyal,...and of particular interest to me for sure.

I'm currently contemplating my management options for fully optimizing my new mains with two dual opposed sealed subs, combined with an IB sub. I've not settled on my loudspeaker management processor, I checking out many options, however I'm looking hard at the dbx 260 (2x6). I've got to decide which avenue soon, as I was just notified today of my pending order shipping status. I'm most likely picking up a new pre-pro too (the 80.3), and it'll have Audyssey XT32. I'll certainly dabble w/Audyssey (albeit w/measured verification). However, with decades of FOH experience, I'm not averse to as much knob twisting (mouse clicking) as it takes to get this right with whatever outboard processor I opt to go with.

You're absolutely right, Audyssey has a place in this industry. It's brought much awareness, and some good measure of optimization to untold number of individuals that otherwise wouldn't be so inclined. As you state, it's manipulation is best suited below the transition, and when blending two subs with some mains it really gets the enthusiast much closer than they otherwise would be merely flying blind. You touched on a much misunderstood topic, minimum phase, when and whys and caveats of EQ'ing above the transition, so good stuff there. It seems Audyssey's flagship processing has been out for a while, I'd suspect they may release the next latest greatest sometime soon. But admittedly, I don't follow their status, nor do I have any idea of which I speak, just sayin' it would seem their product cycle dictates something new....


Thanks


BTW; are you familiar with Xilica loudspeaker management? Mark Seaton wanted me to check them out while I perused the marketplace for my needs.

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post #16 of 40 Old 06-01-2012, 01:42 PM
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Quote:
Originally Posted by Randy Bessinger View Post

My experience with Audyssey (although I haven't used X32) is in line with Dennis Erskine. My experience with Trinnov is it is a different animal all together. At least in my room and I had an Erskine person do my initial set-up with QSC before trying Trinnov. Just my opinion although I think you can find some pretty saavy guys in the LA area such as Sanjay that would echo that.

P.S. Currently using the QSC (Erskine group) for equalizing three subs before input into Trinnov.

I agree, Trinnov is a different animal. You have tons of control over things like the 'house curve' (what you are EQing to), parametric EQ filters, time alignment, etc. Very powerful and also quite expensive! I ended up using a MiniDSP 8x8 on that job I mentioned previously where we turned off XT32 and created our own set of parametric EQ filters. In between MiniDSP and Trinnov there is a bit of a gulf unfortunately...


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post #17 of 40 Old 06-01-2012, 01:51 PM
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Quote:
Originally Posted by FOH View Post

Great post Nyal,...and of particular interest to me for sure.

I'm currently contemplating my management options for fully optimizing my new mains with two dual opposed sealed subs, combined with an IB sub. I've not settled on my loudspeaker management processor, I checking out many options, however I'm looking hard at the dbx 260 (2x6). I've got to decide which avenue soon, as I was just notified today of my pending order shipping status. I'm most likely picking up a new pre-pro too (the 80.3), and it'll have Audyssey XT32. I'll certainly dabble w/Audyssey (albeit w/measured verification). However, with decades of FOH experience, I'm not averse to as much knob twisting (mouse clicking) as it takes to get this right with whatever outboard processor I opt to go with.

You're absolutely right, Audyssey has a place in this industry. It's brought much awareness, and some good measure of optimization to untold number of individuals that otherwise wouldn't be so inclined. As you state, it's manipulation is best suited below the transition, and when blending two subs with some mains it really gets the enthusiast much closer than they otherwise would be merely flying blind. You touched on a much misunderstood topic, minimum phase, when and whys and caveats of EQ'ing above the transition, so good stuff there. It seems Audyssey's flagship processing has been out for a while, I'd suspect they may release the next latest greatest sometime soon. But admittedly, I don't follow their status, nor do I have any idea of which I speak, just sayin' it would seem their product cycle dictates something new....


Thanks


BTW; are you familiar with Xilica loudspeaker management? Mark Seaton wanted me to check them out while I perused the marketplace for my needs.

Being a DEQX dealer I would obviously recommend that for loudspeaker management. They are in the middle of refreshing their product line up as we speak with some new units - the Express II and the HDP-4. Other options are the dbx, Xilica, Lab Gruppen, BSS, etc. Most are pro units and so level matching in a consumer system can be an issue since they are expecting a higher level input signal and the DSP does not perform as well with a lower one. Normally I have people trading up from the dbx to DEQX. Many of those pro LMS (loudspeaker management systems) systems do not have digital inputs either, which in the context of a home theater doesn't really matter but for two channel a lot of people are on music servers now, so why do a D/A then A/D then DSP then D/A when you can just feed a digital input directly into the LMS. Also the pro units are quite often 16/48 whereas the better units are 24/96. I've never used an Xilica unit but the specs on it look good and they seem to have a good reputation in pro circles.

A lot of the money you are paying for the 80.3 is going towards that XT32. If you're not going to use it the lower level pre-pros are fine. Personally I think the Marantz AV7005 is a slam dunk and it sounds awesome. I replaced a Classe processor with it recently and the Marantz sounded better (shock horror!!).


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post #18 of 40 Old 06-01-2012, 03:57 PM
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Quote:
Originally Posted by Franin View Post

Hi All

Just wanted to post this question to people that use Digital Signal Processors (eg QSC DSP 30 etc ) why have they chosen those units over room correction?

I was told Digital Signal Processors give you more an idea whats going on ( which i believe is correct ) compared to room correction which gives you no indication whats going on but as some said the resolution is so much better giving you better results.

Thank you

I think the contrast you are making far more applies to mass market room corrections vs DSP than the sum total of all the solutions which exist. To wit, the JBL Synthesis SDEC-4500 is a 256 channel DSP which then has software that programs it automatically as to give you room "correction"/EQ. As such, it gives you full visibility into what it is doing. Here is a sample low-frequency optimization of the sub:



On top you see the pre/post optimization. On the horizontal line below, you see all the filters automatically programmed for you. Using this display or a much simpler list of filters you can adjust any of them in real-time and get what you want.

I have actually tried to use just the DSP hardware manually without the automatic EQ ("ARCOS"). I can tell you that the process is far more tedious and time consuming. I much rather have it program it and then fine tune manually if needed.

In addition, the EQ does things that you can't do manually. In this case, it can take 4 subs and vary their amplitude, phase and frequency response as to give you the best/flattest response across the seating locations. I have tried to do manually and it simply is not possible. A great example of this optimization logic (SFM) is my Widescreen Review article that just came out in print (it is a slightly updated version of this article on subwoofer optimization):

Without this optimization:



With optimization:


You can see a remarkable reduction in seat to seat variation and smoothness of the response. This came from application of just a single filter to the subs. I don't know how one manually attempts such an optimization.

If you have a situation where you can dial out a few things quickly, then a DSP is fine. But anything more requires tools like this in my opinion.

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post #19 of 40 Old 06-01-2012, 05:01 PM
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Quote:
Originally Posted by Nyal Mellor View Post

Being a DEQX dealer I would obviously recommend that for loudspeaker management. They are in the middle of refreshing their product line up as we speak with some new units - the Express II and the HDP-4. Other options are the dbx, Xilica, Lab Gruppen, BSS, etc. Most are pro units and so level matching in a consumer system can be an issue since they are expecting a higher level input signal and the DSP does not perform as well with a lower one. Normally I have people trading up from the dbx to DEQX. Many of those pro LMS (loudspeaker management systems) systems do not have digital inputs either, which in the context of a home theater doesn't really matter but for two channel a lot of people are on music servers now, so why do a D/A then A/D then DSP then D/A when you can just feed a digital input directly into the LMS. Also the pro units are quite often 16/48 whereas the better units are 24/96. I've never used an Xilica unit but the specs on it look good and they seem to have a good reputation in pro circles.

A lot of the money you are paying for the 80.3 is going toward that XT32. If you're not going to use it the lower level pre-pros are fine. Personally I think the Marantz AV7005 is a slam dunk and it sounds awesome. I replaced a Classe processor with it recently and the Marantz sounded better (shock horror!!).

Nyal, you and I have discussed the DEQX previously. Perhaps I'll revisit this and give it some further consideration. I'll hit your website and check it out.

You make a valid point regarding the Marantz, it's an absolute steal that I often recommend to others in need. It's nice to see you liked the transparency when compared to the Classe. I just felt the feature set on the Integra was stronger, but maybe not,...I'll certainly look again. Maybe I'll take my own advice, and pick one up

Thanks Nyal

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post #20 of 40 Old 06-01-2012, 05:59 PM - Thread Starter
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Quote:
Originally Posted by amirm View Post

I think the contrast you are making far more applies to mass market room corrections vs DSP than the sum total of all the solutions which exist. To wit, the JBL Synthesis SDEC-4500 is a 256 channel DSP which then has software that programs it automatically as to give you room "correction"/EQ. As such, it gives you full visibility into what it is doing. Here is a sample low-frequency optimization of the sub:



On top you see the pre/post optimization. On the horizontal line below, you see all the filters automatically programmed for you. Using this display or a much simpler list of filters you can adjust any of them in real-time and get what you want.

I have actually tried to use just the DSP hardware manually without the automatic EQ ("ARCOS"). I can tell you that the process is far more tedious and time consuming. I much rather have it program it and then fine tune manually if needed.

In addition, the EQ does things that you can't do manually. In this case, it can take 4 subs and vary their amplitude, phase and frequency response as to give you the best/flattest response across the seating locations. I have tried to do manually and it simply is not possible. A great example of this optimization logic (SFM) is my Widescreen Review article that just came out in print (it is a slightly updated version of this article on subwoofer optimization):

Without this optimization:



With optimization:


You can see a remarkable reduction in seat to seat variation and smoothness of the response. This came from application of just a single filter to the subs. I don't know how one manually attempts such an optimization.

If you have a situation where you can dial out a few things quickly, then a DSP is fine. But anything more requires tools like this in my opinion.

Hi amirm
Thank you for your response. Im curious where im able to buy JBL Synthesis SDEC-4500? I went to Harman website but they do not deal outside USA.

Thank you.

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post #21 of 40 Old 06-01-2012, 06:05 PM
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So what everyone seems to say is that if you were to rely on something like Audyssey as the alternative, its very likely that someone could get better results tweaking their system with one of the nice DSP processors. BUT if the room correction system was changed to be Trinnov, or JBL synthesis, or a future Harman SFM product, then the room correction system may be a higher performing option, especially when taking end user error into account if it is assumed that an enthusiast, not a top pro calibrator, is at the helm of the controls?


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post #22 of 40 Old 06-01-2012, 06:14 PM
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Quote:
Originally Posted by Franin View Post

Hi amirm
Thank you for your response. Im curious where im able to buy JBL Synthesis SDEC-4500? I went to Harman website but they do not deal outside USA.

Thank you.

Hi Frank. If you go their web site, there is a drop down for the distributors for each country: http://www.jblsynthesis.com/

Select yours and contact them and they should be able to find a dealer. If you have any issues, PM me and I will get you the right info.

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Quote:
Originally Posted by amirm View Post

Hi Frank. If you go their web site, there is a drop down for the distributors for each country: http://www.jblsynthesis.com/

Select yours and contact them and they should be able to find a dealer. If you have any issues, PM me and I will get you the right info.

Thank you amirm.

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post #24 of 40 Old 06-04-2012, 09:22 AM
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Originally Posted by Nyal Mellor View Post

Normally I have people trading up from the dbx to DEQX.

Hey Nyal,

Again, thanks for your contributions. Tell me, in implementing a multiple sub system (3 currently, perhaps more if needed), why would the dbx260 be in anyway inhibitive performance wise?

Thanks

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post #25 of 40 Old 06-04-2012, 07:47 PM
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Hi FOH if you only need an EQ for multiple subs I'd just use a miniDSP..cheaper than both the dbx and the DEQX. I've used them with great results in four theaters in the last couple of months. At a bit more higher level quality wise (made in US) the go to unit is a Symetrix Jupiter.

If you're talking about a loudspeaker management system then I could write a long long list (see the post above where I started) on the pros and cons of different units.


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post #26 of 40 Old 06-04-2012, 09:35 PM
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Quote:
Originally Posted by hifiaudio2 View Post

So what everyone seems to say is that if you were to rely on something like Audyssey as the alternative, its very likely that someone could get better results tweaking their system with one of the nice DSP processors. BUT if the room correction system was changed to be Trinnov, or JBL synthesis, or a future Harman SFM product, then the room correction system may be a higher performing option, especially when taking end user error into account if it is assumed that an enthusiast, not a top pro calibrator, is at the helm of the controls?

Let me just say I have a different view of this. I have used a number of room correction products: SigTech (may they rest in peace); TacT (both 2 channel and SSP version); one of the QSC products and Audyssey XT and X-32 (Pro). While Audyssey (Pro) may not be the king of room correction systems, I believe it to be MUCH better than is suggested here.

If one is willing to read the over 2 billion posts on the Audyssey thread paying particular attention to the very well thought out FAQ's and set up instructions (as well as some of the after-Audyssey tweaks that are discussed), one can get OUTSTANDING results - Audyssey X-32 is significantly better in every respect than the previous version, particularly in the mid and lower bass. Bass ringing in my well treated room is very good. With Audyssey X-32 (on an Integra 80.2) it is incredible. And with Audyssey Pro, I have a lot more flexibility to "diddle" with the target curve.

And while I have more experience than most on using various room correction products (including one of the QSC products), learning to be proficient with Audyssey does NOT require the use of an outside calibrator. And in my experience, it would be highly unlikely that one could get the reduced bass ringing I have experience by using something like a QSC product. As an aside and to show my bias, I am not convinced that ANY frequency based room correction product (like the QSC) will ever be able to keep up with the time-based products (TacT, Audyssey, Trinnov, Dirac). While the TacT has some outstanding technology, it did not do anywhere near as well in managing the bass ringing as did my Audyssey based SSP.

I am not suggesting that Trinnov or Dirac (or the Harmon product) are not better products. I am suggesting that Audyssey Pro when used with much care can give incredible and outstanding results!

R 8:28


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Quote:
Originally Posted by audioguy View Post

While Audyssey (Pro) may not be the king of room correction systems, I believe it to be MUCH better than is suggested here.

If one is willing to read the over 2 billion posts on the Audyssey thread paying particular attention to the very well thought out FAQ's and set up instructions (as well as some of the after-Audyssey tweaks that are discussed), one can get OUTSTANDING results

I too have gotten outstanding results using Audyssey Pro, with consistent improvements in two very different high end systems.
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post #28 of 40 Old 06-06-2012, 02:32 PM
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Quote:
Originally Posted by Nyal Mellor View Post

Hi FOH if you only need an EQ for multiple subs I'd just use a miniDSP..cheaper than both the dbx and the DEQX. I've used them with great results in four theaters in the last couple of months. At a bit more higher level quality wise (made in US) the go to unit is a Symetrix Jupiter.


If you're talking about a loudspeaker management system then I could write a long long list (see the post above where I started) on the pros and cons of different units.

Nyal,

I've considered the miniDSP, as so many of the diy crowd here at AVS really rave about using them since their release. I hadn't planned on running the mains thru the processor, just handling of the manipulation of a multi-sub set-up. There are some additional features of the dbx that do appeal to me, and it's a robust, mature platform that I'm relatively familiar with. All that said, I'm not locked into anything, I appreciate the heads up on the Symetrix piece. I'd forgotten about it and the performance audio guys rave about it and it's likely of sufficient quality to pass the mains with full transparency,...this would give me more tools above the LFE/RB cross, yet still below the transition. But I know little about it and am downloading the interface now to poke around.

Thanks

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Quote:
Originally Posted by hifiaudio2 View Post

So what everyone seems to say is that if you were to rely on something like Audyssey as the alternative, its very likely that someone could get better results tweaking their system with one of the nice DSP processors. BUT if the room correction system was changed to be Trinnov, or JBL synthesis, or a future Harman SFM product, then the room correction system may be a higher performing option, especially when taking end user error into account if it is assumed that an enthusiast, not a top pro calibrator, is at the helm of the controls?

It basically comes down to the ability to manually intervene and make further knowledge based adjustments that make the other units,with more manual adjustments, more attractive.Most of these units have an automated calibration routine function that many feel doesn't give the best results.However,I think most of the RC companies would argue that their automated routines can do a better job than what most typical users could do manually;).
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post #30 of 40 Old 06-06-2012, 03:45 PM
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The Jupiter looks interesting, but a couple of things:

Does it have all of the functionality of the MiniDSP 8x8?

That includes processing down to 10 Hz.

What's with the terminal block inputs/outputs?

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