[EndersShadow]

Summary:

A long time ago this thread about a DBX PA2 clone caught my eye. It was a pretty neat piece of gear, providing solutions for many of the pet peeve's (phoenix connectors, lack of network control, wallwart) of the MiniDSP platform that caused me to come up with my own custom solution. At the time I was planning some upgrades to my unit to add network connectivity via a WI-DG, as well as limit noise via a miniDC Isolator. I was also thinking about replacing the wallwart with either a better one, such as the iFi iPower DC Power Supply or going all in with a linear powersupply (example 1, example 2)


After purchasing both the WI-DG and miniDC Isolator, I learned the hard way that the WI-DG is not compatible with either the 2x4 RCA or 2x4 Balanced (the 2x4 HD and most other newer models are). I remembered and revisited the AVS thread, and then really dug into research mode about the PA2 to see if it would be a suitable replacement, if not upgrade to what I was using.

I found a lot if information out there, including walkthroughs of the software and reviews of the product and its possible applications. These really helped me in evaluating the PA2 prior to purchasing, however it also lead to a bit of analysis paralysis. After quite a bit of research I decided that I just needed to dive right in and grab one. I also thought that perhaps others may find the information I'd gathered useful.

This particular post is more of a feature and cost comparison. Additional posts will cover results/observations. For those wanting to do their own research, see the research section at the bottom of this post for links to reviews and videos.

Disclaimer

Before we go any farther I feel the need to clarify a few things.

1. I am not a professional reviewer, nor do I claim to be. If any of my information is incorrect, let me know so I can correct it.
2. I do not plan to spend the next weeks recording and providing tons of measurements, etc. Yes I know this is Audio Video Science, but to be blunt I don't:
   
   Care to spend the time to do so. This is my hobby, not my job. I have a wife and 2 small children and I will always prioritize spending time with them playing, or watching movies, over measurements.
   
   Feel like tearing apart and re-arranging my gear 12321 times. I am currently recovering from a serious non-COVID medical condition and am very weak, so something that used to take me 5 minutes may take me 30, and simply do not have the strength to do it.
   
   I do plan to take some measurements as I incorporate the PA2 into my system as its somewhat required to do so. I also have some prior measurements of my system with the MiniDSP. When possible if I can provide graphs that are a accurate A/B comparison using that prior data I will do my best to do so.
3. I also am of the belief (for better or worse) that some things you feel/hear cannot be adequately measured. I will likely use words that will drive some of you bonkers, including: Expansive, Depth, Soundstage etc. While it may be possible to measure some of them by graphing things like (distortion, etc), refer to Item #2.

Feature Comparison

When contemplating a purchase, I like to make Pro's and Con's lists to try and understand what I'm gaining or problems I'm solving, as well as what I'm losing, or problems I'm creating. The list below is what I came up with for the PA2. Since I already had the MiniDSP, and it would cost me 0 dollars to keep it, I felt it made sense to start with the drawbacks of the PA2 rather than the strengths.

DBX PA2 Cons:

• The Inputs must be EQ'd together. You cannot apply a diff EQ to the right input than the left. - For me not a problem
• Delay is 7ms (which is the same as the standard MiniDSP, but other MiniDSP products have higher delay available) - Not a problem for me as I was already limited to 7ms but since I really have 2 pair of equidistant subs, wont know till the other pair is completed. And even if I do need more than 7ms, I may be able to compensate by playing with the "Distance" setting in my AVR.
• Each set of L/R outputs must be EQ'd together. This means while there are 6 outputs, you really only have 3 stereo pair. - Given my configuration, this should provide me enough options, and possible even allow for the addition of a set of MBM's.
• LCD screen is a bit bright and cannot be dimmed - easily fixed by purchasing an item like these LightDims Black Out Edition
• I read it outputs a fair amount of heat. I've yet to confirm this.
• Wont EQ below 20hz. You can use the same trick for the iNukes to set a highpass filter below 20hz for ported subs. - I'm using sealed subs so while it would be nice to be able to EQ below 20hz, I honestly will just use the iNuke trick to set a highpass at around 15hz which will both: protect my subs from overexcursion and allow me to push the system a bit more as a result
• 8 PEQ bands on Input and Output. The Mini has 10.
• Lack of support of the Home Theater enthusiast masses, which has resulted in various custom solutions based around the MiniDSP architecture.
  • Bass EQ is designed around the mini. You can do same with most peq but the streamlined process is all mini. *added thanks to @Vince_B
  • MSO also designed around the MiniDSP platform *added thanks to @Vince_B

DBX PA2 Pro's:

• Multiple ways to program: LCD on the faceplate, Laptop/iOS/Android app, which is like having a built in WI-DG
• Quick Access buttons to program various pieces such as Xover, Delay, Limiter, etc
• Mute buttons for every input/output on the unit, and in the software
• Has its own AutoEQ with the addition of a RTA-M microphone
• Multiple Presets can be created, and recalled easily. This means I can have one preset for most viewing (aka when my wife who isn't a fan of large amounts of bass), and another for when I'm home alone and want to crank it to 11.
• Native XLR input and outputs. To get this with my Balanced unit, I had to spend a fair amount for a custom enclosure, which I love, but I'm still using phoenix connectors internally
• Toroidal Transformer rather than wallwart. wallwarts can introduce noise into a system
• Standard Size for rack mounting or placement in a cabinet
• LED's for signal strength for input and each channel
• Inputs can be configured for either +4dBu/-10dBv usage. From what I'm reading AVR users would want to use the -10dBv setting, while those with Processors would want to use the +4dBu setting. I have mine at the -10dBv setting with my Denon.
• Ground lift switch - useful to try and fix any ground loop hum

Feature Summary: After reviewing the list above, in my particular situation the pro's far outweighed the cons, since most of them have workarounds or a non-factors.

Cost differential:

DBX PA2

New a DBX PA2 will cost you around 440. Lightly used/refurbished units can be found on eBay for around 200-250 if you are patient. The DBX RTA-M mic new will cost you 100. As with the PA2, you can find open box/used mics for around 60 on eBay. For those that want a new unit at a lower price, there is a "clone" available from Sinbosen for around 200 USD last time I looked.​

​

Authors note about clones: When possible, I prefer to buy EOM models (new or used). The bargain hunter/cheapskate in me appreciates the pricing of clones as it sometimes puts something within grasp that otherwise would not be. The idealist in me struggles with the fact that by purchasing them I am funding/encouraging those performing Intellectual Property Theft to continue to do so.​

​

I went the used route and my PA2 cost me 208 after tax and the RTA-M cost me 60 for an all in cost of 268.​

MiniDSP

A MiniDSP is going to cost you a minimum of 104 (2x4 RCA) to 209 (2x4 HD). The WI-DG is going to run you about 90, and a UMIK mic will cost anywhere from 90 (parts express) to 110 (Cross spectrum calibrated mic). My recommendation is always for the Cross Spectrum since its a more accurate and is calibrated higher and lower than the stock model.​

​

So all in, the cheapest you can get away with for a MiniDSP system is around 304 dollars (104 2x4 + 90 WI-DG + 110 Cross Spectrum UMIK-1). Given that most people would recommend the 2x4 HD all day over either the 2x4 or 2x4 balanced, the more appropriate cost for a MiniDSP setup is 409 (209 2x4 HD + 90 WI-DG + 110 Cross Spectrum UMIK-1). I am sure given time and patience you could spend less by buying used as they come around, but it will take longer to source 3 pieces used.​

Cost Summary: Depending on what configuration MiniDSP you plan to employ the PA2 may save you some cash

Final Summary: On paper at the end of the day the PA2 is a good contender to go up against, and possibly beat the MiniDSP.

Addendum: DBX also offers a model that is a step up from the PA2, called the Venue 360. It adds a few additional bells and whistles. If your budget allows, make sure to check it out as well. At the time of this purchase (12/25/2020) the Venue 360 was hard to find used, and those that I did find were 1.5 times more expensive than the PA2. Additionally new was not an option at all, and for those who do not have the internal conflict I do about buying a clone, the Sinbosen option was not available either.

__

Research

There are quite a few videos out there that really dive in deep into the software, as well as numerous reviews. While many of them are focused on the pro audio demographic (which makes sense given this is a pro audio device) and discuss various professional speakers, venues, etc, reading them let me understand various applications of the product and provided insight into what problems I might encounter in the Home Theater realm. To get you started, I've listed just a few of them below.

Videos:

• dbx DriveRack PA2 Custom Speaker and Amplifier Setup - dbx
• dbx DriveRack PA2 Loudspeaker Signal Processor Overview - agiprodj
• DriveRack PA2 Review! - code

Reviews:

• Dbx DriveRack PA2 - Sound on Sound
• Review: dbx DriveRack PA2 Loudspeaker Management System - American Songwriter
• dbx DriveRack PA2: The Future of Audiophile Systems - Audiophile Nirvana (skip the other linked articles. They don't really dig much more into the PA2 further)

 

[EndersShadow]

Reserved 1

 

[EndersShadow]

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[EndersShadow]

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[EndersShadow]

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[EndersShadow]

Reserved 5

 

[Wayne A. Pflughaupt]

Be interested to see your evaluation!

Eight EQ filters per (whatever) is more than enough. My Yamaha EQs only have six, and I only use two or three.

I would have taken a pass on the dbx mic. Unless comes with a custom-generated calibration file that can be loaded into the PA2, it’s not going to be as accurate as a UMIK.

Regards,
Wayne A. Pflughaupt

 

[Wayne A. Pflughaupt]

delete, accidental double post

 

[Vince_B]

Interesting stuff, especially since having just wasted hours messing with a bad minidsp (intermittent usb failure, dsp worked). However the mini has the crowd advantage so you could add to the dbx cons list:

-bass eq is designed around the mini. You can do same with most peq but the streamlined process is all mini.

-mso pretty much same. And rew for filter export, I don’t do that but it’s out there. The mini is so ubiquitous it has crept into all these other apps.

 

[EndersShadow]

Be interested to see your evaluation!

Wayne, as someone whose always enjoyed reading your detailed discussions on things such as House Curves and Subwoofer integration I hope you are not expecting anything near your caliber of content hehe..... I dont think you can see your bar from where I am

Eight EQ filters per (whatever) is more than enough. My Yamaha EQs only have six, and I only use two or three.

Yeah, I didn't think that was a show stopper, but wanted to be thorough in the pro's and con's list.

I would have taken a pass on the dbx mic. Unless comes with a custom-generated calibration file that can be loaded into the PA2, it’s not going to be as accurate as a UMIK.

I'm not sure TBH, but the PA2 wizards require it to work and I was trying to make integration as easy as possible, and provide as good of a A/B comparison. This tracks with the fact that many folks with the MiniDSP are utilizing it in tandem with the REW and UMIK to make creation and import of filters as painless as possible.

I've yet to do more than open up the RTA-M mic. The dbx PA2 has been installed and while I have some initial thoughts, I wont share them as they are likely biased and could be based on settings that give an unfair advantage to the PA2 over the MiniDSP.

Without the mic I'd have to do a lot more manual entry, configuration, and run a lot more wires to calibrate (HDMI from laptop to AVR, USB to UMIK-1 mic, USB to MiniDSP) compared to just a single XLR from the PA2 to the mic (somehow the XLR cable provides power from the PA2 to the mic as well as signal).

I do still plan on using the UMIK-1 to measure some before and afters. Also since the PA2 is downstream of the AVR, its only measuring and calibrating the subs, and the sub/main integration will happen through XT32.

Question:

@Wayne A. Pflughaupt, given you've done quite a lot of writing on calibration, house curves, mixing consumer and pro audio together I do have a question for you (or anyone else reading). The PA2 has multiple wizards (listed below), and I'm not sure which ones I should run, and the order (including XT32) to run them in.

Additionally I'm unsure if I should configure the system as mono or stereo. If I chose stereo it provides the opportunity for XT32 to provide additional delay (should 7ms in the PA2 not be enough) by utilizing the Distance settings. The current 2 subs (with 2 more on the way) are located on the sides of my room facing inward towards the middle and XT32 set the distances at 10.4 ft and 8.9 feet respectively. The 2 remaining subs (2 DO 3.7 cf sealed sonotubes) with be placed near my mains (either on the inside or outside of them).

• Run All Wizards: Select this option to run through all the Wizards in succession
• Run All Setup: Select this option to run through the entire Setup Wizard (which consists of all Setup Wizard items listed below).
  • Run Input Setup [MONO, STEREO]: Select this option to switch the input configuration between mono or stereo.
  • Run GEQ Setup [DUAL MONO, STEREO LINKED]: Select this option to switch the GEQ configuration between dual mono or stereo linked.
  • Run Speaker/Amp Setup: Select this option to update speaker and/or amp selections (tunings)
• Run AutoEQ/Level Assist: When used with the optional dbx RTA-M measurement microphone, this Wizard helps you balance the left/right speaker levels, the low/mid/high speaker levels (for 2-way and 3-way systems), and automatically equalizes the speakers to the current room environment. After selecting this option, you can select whether you would like to run both the Level Assist and AutoEQ functions, Level Assist only, or AutoEQ only.
• Run AFS Wizard This Wizard walks you through the process of ringing out the system to provide higher system gain before feedback <- dont plan on running this

Any thoughts or opinions appreciated.

 

[EndersShadow]

Interesting stuff, especially since having just wasted hours messing with a bad minidsp (intermittent usb failure, dsp worked). However the mini has the crowd advantage so you could add to the dbx cons list:

-bass eq is designed around the mini. You can do same with most peq but the streamlined process is all mini.

-mso pretty much same. And rew for filter export, I don’t do that but it’s out there. The mini is so ubiquitous it has crept into all these other apps.

Thanks those were added to the list under a single bullet.

 

[kevinzzz]

You can pick up a used BSS Soundweb London for a couple hundred bucks now.... complete freedom to write your own processing chain and TONS of DSP resource. A BLU-100 with 12 ins and 8 outs can be had for about $400-$500 and an older (but still current software!) BLU-80 or BLU-16 for $200-$300 if you wait for the right one (gotta watch for what cards are loaded though) also those will do 96Khz sample rate.

 

[EndersShadow]

You can pick up a used BSS Soundweb London for a couple hundred bucks now.... complete freedom to write your own processing chain and TONS of DSP resource. A BLU-100 with 12 ins and 8 outs can be had for about $400-$500 and an older (but still current software!) BLU-80 or BLU-16 for $200-$300 if you wait for the right one (gotta watch for what cards are loaded though) also those will do 96Khz sample rate.

That's great information, thanks for posting it. I'd never heard of that particular company before. There are many, many alternatives to the MiniDSP platform, especially if you are willing to buy used. That said, for me personally having to write my own processing chain, while providing the utmost flexibility, would still be problematic. Refer to Disclaimer #2.

For those with the time and willing to put in the additional sweat equity those may be very good options. It also helps to have a large fan/resource base. While the PA2 has an "OK" amount available, the MiniDSP platform dwarfs it.

Thankfully my configuration is nothing crazy (especially compared to most other posters in this section). I'm just looking to use it to EQ 4 subs, and allow me to add some custom shelf filters, etc to adjust the bass to my taste.

While the PA2's feature set is limited to what it comes with, it was one that I determined met a majority of my current needs, and added some flexibility for some of my foreseeable future needs (such as more subs, moving to a Pre-Pro instead of an AVR, etc.)

For anyone else aware of another viable platform, feel free to post it. While I wont be reviewing/analyzing them, its always good for people to be aware of other options that might suit their needs better than the MiniDSP or PA2 platforms.

 

[FOHTech]

Ive run these in my system for several years. One Venue360, one PA2 and two PAs (previous model to the PA2). One RTA mic.

I am actively processing my scratch built LCRs with the 360, Subs (2 way multiple sub setup to one single channel LFE) on the PA2, and my side and rear surrounds (also actively processed 2-way scratch builds) actively processed on my PAs.

Yes the PA2 gets VERY HOT. No power switch so I have to remrmber to always kill the power to it ASAP. Need to get a fan over it.

I had one ebay purchased refurbished PA2 die on me after leaving it on overnight. No visible issues on the board upon inspection. I need to send it in to dbx for repair. Its been sitting on the bench for over a year now waiting for me to get around to it.

I do most everything manually and use REW as well. The UI apps are fantastic in my opinion. The difference in noise compared to the MiniDSP is night and day.

I do delays and levels on the dbx products for reference level to the MLP manually and then the Pre/Pro and Audyssey tweaks it further.

I have a few stored presets in each to go from a movie flat system, movie LFE hot setting, and to a music based house curve and tweaked system which the levels and curves are totally different. Super simple to recall the presets.

I come from a Pro Audio world and these were a natural transition for me.

If I didnt have 7 channels of DIY actively processed builds, not sure I would have gone this route to be honest. If I had a 7.2(or more) JTR OEM rig for example, I wouldnt bother with this expense, there would really be no reason to. MSO on a Mini 88 would be the best route there


Sent from my iPhone using Tapatalk

 

[EndersShadow]

Tonight while the family slept I took the opportunity to play around a bit more with the software. Since they were sleeping I was NOT able to run of the wizards. Instead I continued to read (and I mean really read, not just skim) the manual. Since I couldn't run the wizards, I skipped by their section and found myself in the Manual System Optimization Tips section.

First I adjusted the Crossover Frequency and Filter settings. This was pretty easy to do so I dont feel the need to elaborate.

From there I proceeded to Setting Driver Alignment Delays and Polarity. Since everyone was asleep I was unable to test if I needed to invert the polarity on one of my subs. My recollection was that when using the MiniDSP after various measurements I found it was best to not invert one sub. Additionally the delays for my current subs were best when set to 0.

After wrapping that up, next up was Setting Gain Structure and Limiters. This is one thing I always struggled with while using the MiniDSP and one I was keenly aware was very important to get right. With the PA2 I was determined to really dig in and try to optimize it properly. The majority of my testing time tonight was spent here.

I have a set of amplifiers, one is fairly well known, the Crown XLS2000. The other is a Chane 3600, which is from a not as well known brand (Chane Music and Cinema) and is a rebadged amp from an even lesser known OEM (Suntron), specifically the Suntron model MQ-600. In addition to using amps from two different companies, both amps utilize different topology. The Crown is a Class D, while the Chane is Class A/B.

I do have two Chane 3600's, which were both purchased for a song due to the need for some troubleshooting and repair. The second amp is not yet up and running. Once it is, I plan to use both Chane 3600's to help simplify the setup.

Each amp is bridged and powering one of my two subs. Eventually each amp will drive a PAIR of subs as I am slowly working toward 4 subs.

If you are using the Setup Wizards, and somewhat common amplifiers, things are easy. During the setup process you select the amps you are using from the list and it automatically sets the limiter thresholds and gain structure for you. If however, your amps are not shown, you select "Not Listed" and then have to manually set the gain structure using the procedures found on page 21. I went ahead and for practice used those procedures for both amps.

One additional wrinkle with my particular setup is that I have set the internal max volume on the Denon to 80. This was done as a precaution since I have little kids and I don't want them to blow everything by getting crazy with the volume knob. As a result the input signal to the PA2 is limited compared to what it could be. To compensate I adjusted the Subwoofer Level Adjust (found in Settings/Audio) to +10db as well as increasing the Level (found under Speakers) to +7. This provided almost enough signal to light up the clip lights on the input signal.

While following the instructions I discovered I needed to put each amp on its own output channel as the Crown clips at around 75% on the attenuation dial, while the Chane's attenuation dial must be set to 100%. So I moved the Chane to the MID output.

The final settings for the limiters were -2.5 db for the Chane, and -1 db for the Crown. At this point it was going on 2:30 AM EST so I decided to turn in and finish writing this.

I will attempt to run some of the Setup Wizards tomorrow.

Goodnight (for me), Good Morning (for most of you).

 

[EndersShadow]

Ive run these in my system for several years. One Venue360, one PA2 and two PAs (previous model to the PA2). One RTA mic.

I am actively processing my scratch built LCRs with the 360, Subs (2 way multiple sub setup to one single channel LFE) on the PA2, and my side and rear surrounds (also actively processed 2-way scratch builds) actively processed on my PAs.

I do most everything manually and use REW as well. The UI apps are fantastic in my opinion. The difference in noise compared to the MiniDSP is night and day.

I do delays and levels on the dbx products for reference level to the MLP manually and then the Pre/Pro and Audyssey tweaks it further.

I have a few stored presets in each to go from a movie flat system, movie LFE hot setting, and to a music based house curve and tweaked system which the levels and curves are totally different. Super simple to recall the presets.

I come from a Pro Audio world and these were a natural transition for me.

If I didnt have 7 channels of DIY actively processed builds, not sure I would have gone this route to be honest. If I had a 7.2(or more) JTR OEM rig for example, I wouldnt bother with this expense, there would really be no reason to. MSO on a Mini 88 would be the best route there

Awesome thats a ton of great info. I do plan to setup a few presets such as:

Full Range Subs Normal
Full Range Subs Hot
Full Range Subs Demo

I do most everything manually and use REW as well. The UI apps are fantastic in my opinion. The difference in noise compared to the MiniDSP is night and day.

I do delays and levels on the dbx products for reference level to the MLP manually and then the Pre/Pro and Audyssey tweaks it further.

Good to know. I may try doing it that way.

Yes the PA2 gets VERY HOT. No power switch so I have to remrmber to always kill the power to it ASAP. Need to get a fan over it.

I had one ebay purchased refurbished PA2 die on me after leaving it on overnight. No visible issues on the board upon inspection. I need to send it in to dbx for repair. Its been sitting on the bench for over a year now waiting for me to get around to it.

Good to know. I think there is enough space around it for now. Its in one section of my entertainment center. The bottom has some large slots cutout for airflow, and the back is wide open. Additionally its placed on some 2.5" rubber spacers. The spacers are actually rubber stoppers used in large scale pharmacy production. My dad is in that line of work so I ask him to bring me all he can and use them for this purpose. It has about 5" of space above it for hot air to rise. I have a fair number of 120mm computer fans so I will try to cobble together some to sit on top of it until I can afford to buy another AC Infinity Aircom S9 or AC Infinity S8 to put on top of it. I may even look for one of the T series so I can easily see the temperature.

Also we are on night two so far without issue. I may start taking the cabinet door off each night before bed, or connect it to a powerstrip, or something like that kill power to it each night

 

[Wayne A. Pflughaupt]

Wayne, as someone whose always enjoyed reading your detailed discussions on things such as House Curves and Subwoofer integration I hope you are not expecting anything near your caliber of content hehe..... I dont think you can see your bar from where I am

Wow, I appreciate the kind words!

Yeah, I didn't think that [the number of filters] was a show stopper, but wanted to be thorough in the pro's and con's list.

Duly noted, and I’m sure anyone perusing this thread appreciates the information.

@Wayne A. Pflughaupt, given you've done quite a lot of writing on calibration, house curves, mixing consumer and pro audio together I do have a question for you (or anyone else reading). The PA2 has multiple wizards (listed below), and I'm not sure which ones I should run, and the order (including XT32) to run them in.

Obviously some of the wizards are of more use to the home theater user than others, which you’ve already figured out. I’d say if running stereo is beneficial to you (e.g. the delay feature), then by all means do it. However, typically you’ll want any filtering to be identical for both outputs.

Re the auto EQ function, by all means try it out, but don’t be discouraged if it doesn’t work all that well for your subs. Except perhaps for the smallest ones (think coffee house), live performance venues aren’t plagued by all the room modes and nulls in low-end response we find in home theater rooms. As such, low freq EQ in performance venues is a comparatively easy task. Thus, be prepared to use REW and manual set up your filters if needed.

After wrapping that up, next up was Setting Gain Structure and Limiters. This is one thing I always struggled with while using the MiniDSP and one I was keenly aware was very important to get right. With the PA2 I was determined to really dig in and try to optimize it properly. The majority of my testing time tonight was spent here.

In my estimation gain structure and limiting is likely much less important with the dbx compared to the miniDSP, because the dbx has tons more headroom. IOW, clipping the dbx shouldn’t be a concern with a consumer front-end providing the signal. There really shouldn’t be any gain structure issue using a modern pro-audio processor in a home system: Basically the signal passes straight through. The main issue, if any, will probably be with the dbx output signal being too low or too high for the destination amplifier, due to wholesale gain changes brought by the EQ filters. If this is the case, the dbx output levels can be adjusted to compensate.

Regards,
Wayne A. Pflughaupt

 

[EndersShadow]

Obviously some of the wizards are of more use to the home theater user than others, which you’ve already figured out. I’d say if running stereo is beneficial to you (e.g. the delay feature), then by all means do it. However, typically you’ll want any filtering to be identical for both outputs.

Re the auto EQ function, by all means try it out, but don’t be discouraged if it doesn’t work all that well for your subs. Except perhaps for the smallest ones (think coffee house), live performance venues aren’t plagued by all the room modes and nulls in low-end response we find in home theater rooms. As such, low freq EQ in performance venues is a comparatively easy task. Thus, be prepared to use REW and manual set up your filters if needed.

I'm still on the fence about the need for delay between the current subs. XT32 did set different distances for the subs. In theory I could just transfer that distance (aka delay) into the PA2 and then just run it with a single sub out. It would depend on how the EQ results work out.

In my estimation gain structure and limiting is likely much less important with the dbx compared to the miniDSP, because the dbx has tons more headroom. IOW, clipping the dbx shouldn’t be a concern with a consumer front-end providing the signal. There really shouldn’t be any gain structure issue using a modern pro-audio processor in a home system: Basically the signal passes straight through. The main issue, if any, will probably be with the dbx output signal being too low or too high for the destination amplifier, due to wholesale gain changes brought by the EQ filters. If this is the case, the dbx output levels can be adjusted to compensate.

You are correct. Even with the volume limiter on the Denon off, I had to boosting the stuffing out of the signal to get it to clip, and even then juuuuust barely.

When adding the volume limiter on the Denon of 80 it became outright impossible, even after setting the Audio/Subwoofer Level Adjust to its max setting of 12db, and the Speakers/Levels to 12 (for reference the mains are at -4 and the center is -9.5).

So far today when watching regular TV my wife's only comment was "What did you do to the speakers [subs]"....... I then followed it up with a lengthy explanation as to gain structure, why it was important, etc. She respectfully acted like she was interested and let me go until I was finished.

I do agree the bass is quite bloated currently and am slowly dialing it back in the Denon. Thankfully like the PA2, the Denon firmware can be access remotely, so I've slowly been bringing it down.

The way I know the bass is bloated is that the intro to friends sounds like a war soundtrack and my oldest daughter (in her room on the second story which is NOT above the family room) complained about it lol

I can also confirm that the noise level in the PA2, as well as the overhead are spectacular.

For now I've dialed back the Audio/Subwoofer Level Adjust to 6db and the Speakers/Levels for the subs to 0.

 

[EndersShadow]

When looking to use the dbx Wizards paired with the RTA-M mic there was quite a bit of trial and error. To save someone else the trouble, here are the things I learned. There may be workarounds or ways to do things better, but I refer you to Disclaimer #2

• Presets:
  • I quick review showed no preset for just subs. Everything assumes you need a full signal
    • Workaround: I was able to configure a system consisting of passive stereo mains and stereo subs. I simply did not hook up anything to the Mid or High input. The measurements however were still for the full spectrum, and the EQ was also based on the full spectrum. This is what I used to get my measurements further down
• Wizards:
  • Setup Wizard
    • No way to select a sub only setup
      • Min is a Main + Sub setup
  • AutoEQ
    • Both channels of a given output must be connected, e.g. cannot connect just the Left Mid without Right Mid
    • AutoEQ does not work for all placements
      • Works if:
        • Subs placed along front wall pointing toward main LP
      • Possibly problems if:
        • Subs placed on sidewalls facing inward
        • Subs are nearfield behind user
        • Subs at front and back
      • Level Assist
        • Not useful if both amps not in database
  • RTA
    • Couldn't figure out how to get it to generate a signal

I decided I really wanted to make the wizards work, so in order to use it I did the following with my setup:

1. Told the Setup Wizard I had Passive Mains + subs
2. Put both subs on Crown
3. Set Crown to stereo from bridge
   • Note: At this point I discovered both Speakon's were wired wrong. Both amps when bridged require the positive to be on +1 and the negative on +2. Both were connected with the positive on +1 and the negative on -1 neg. I have no clue how, or if this could have affected speaker performance since the incorrect wire is the ground.... perhaps I was simply running the speakers ungrounded? or perhaps both with inverted phase compared to my mains/center? I also was not sure if this could have affected my work to manually set Gain Structure and Limiters may be incorrect. Left it alone as for this testing the wiring was correct
4. Ran EQ using the following positions
   
   
5. Came up with the following result
   

Given I did not need to EQ the full spectrum I zero'd out any filter above 120hz as they were pointless. After all was said and done, I was left with the following filters:

Number	Frequency	Gain	Q
1	76.2	-12	0.58
2	48.7	-12	1.38
3	96.2	-3.3	6.32

In looking at the filters and comparing them to prior filters from some of my original measurements, it seems like I should have a few more filters than what I got. The filters the PA2 was adding did have correlating ones in the REW measurements, but the REW data also had a few more. I also was unsure if my unconventional measurement locations due to my setup compared to what the manual states should be used would result in inaccurate results.

Spoiler: Spoiler about AutoEQ v MiniDSP

After completing all my REW/UMIK measurements the PA2 filters may have worked just fine See Questions at bottom of post, but having correlating data is never bad. The REW Filters are more accurate but sometimes overcorrecting can be an even bigger problem than not correcting it.

I decided to revert to using REW to measure my subs via a UMIK as I was a little bit more comfortable with REW. This method allowed me to measure with the Crown bridged and Change bridged as I intended. I also corrected the speakon wiring at this point.

Without confirming I don't need to use different filters in the PA2 I cannot continue onward to run XT32.

1. On the PA2:
   • Use the Left/Mono input ONLY (RCA out of Denon -> Cardas RCA to XLR adapter -> PA2)
   • Set to Preset 13 (which is Stereo Full Range), and mute all the Right channels
   • Connect the amps to the following
     • High Left - empty
     • Mid Left - Chane
     • Low Left - Crown
2. Re-check Gain Structure and Limiters on the PA2 since speakers now are using correct wiring (+1 pos +2 neg instead of +1 pos -1 neg)
   • In the Denon:
     • Volume still limited to 80
       • I used the below YouTube video for my pink noise
         
     • Audio/Subwoofer Level Adjust set to +6
     • Speakers/Levels set to 0
       
       Note: With the settings above I was unable to clip either the subwoofer input or output. I decided to leave the limiters off, and also I left the amp attenuator knobs at their max values per previous gain testing
3. Create EQ Filters by using UMIK + REW
   • In the Denon
     • Turn Audyssey off (Audio/Audyssey)
     • Set Subwoofer to 1 (Speakers/Speaker Config.)
     • Set Crossovers to 250hz (Speakers/Crossovers, Speakers/Bass, Speakers 2ch Playback)
     • Set to LFE+Main (Speakers/Bass & Speakers/2ch Playback)
4. Take filters from REW and input into PA2

I took measurements at the following locations. I only measured up to 250hz as honestly I don't ever think I will set the value above 80hz (120hz if the world falls apart). Because everyone was sleeping, I tried to just keep things simple. I set the volume to 50 on my Denon and then took all my measurements. I've attached a file containing all the groups of measurements, as well as the various average files created using them. After downloading it, change the .txt to .zip and extract the contents.

Then I averaged all the measurements and used that average to create a set of EQ filters in REW. I was pretty lenient on the Filter Tasks as in playing with it I found that the differences between higher Individual Max Boost Overall Max Boost,, and Flatness Target didn't really change the overall shape that much. However changing the Target Level to 87 from 90 amounted to a pretty big shift in the 20-30hz range (there was a 6db dip otherwise). And from what little I remember a 6db difference is an audible difference. I should also say that only using 4 filters, none of which have a high Q, or too crazy of a gain value makes me think I set them correctly as I seem to remember something about that being a way to tell if you were doing too much.

I then manually entered those EQ Filters into the PA2's AutoEQ section. Not all the values could be entered identically to REW. All of them are + or - .1 however.

Here are my questions:

• Did I measure good locations?
• Are there any measurements in each group that I should throw out and if so which ones?
• Should I have used the average of all of the measurements or a smaller subset (e.g. Front + Middle, just Middle, etc).
• Did I set the REW Filter Task values too wide? too narrow? just right?
• Anything else obvious you can see

Until I am comfortable that I got a good starting point in the PA2 I wont be moving forward with running XT32, which is the next step.

My next steps after confirming I have a good baseline is to:

1. Run XT32
2. Return to the PA2 and add any additional EQ such as low shelf filters, etc
3. Double check Gain Structure and Limiters
4. Crank it and enjoy! Still trying to decide what the 1st film on my new configuration will be