Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[candycane]

I'm thinking of either buying a fancy receiver that includes something like Audyssey room correction, or going the HTPC route with MC, a DAC/preamp and power amp.  Have you considered offering an option or plug-in that integrates a room correction package?  Something like Audyssey MultiEQ or the like in software form (preferred), or Room EQ Wizard (not as preferred but pretty good too)?  Perhaps license something from an existing room correction outfit, integrate it into MC, add a microphone, and with our HTPC have a really capable and flexible sound processor that would rival very expensive setups.

Do you have something like this already?  If not, anyone else crave something like this?  With an HTPC and the sophistication of these tools, use could range from fairly automated to very tweaky with just software settings.

[JimH]

Under DSP Studio, MC has a Room Correction feature.  It doesn't use a microphone, so you need to set it manually.

Picture attached.

[cncb]

Do you have something like this already?  If not, anyone else crave something like this?  With an HTPC and the sophistication of these tools, use could range from fairly automated to very tweaky with just software settings.

I have thought about something like this but unfortunately I think it would be too expensive.  For example, there is an Audyssey VST that exists but it is on the range of $500.  For around that same price you can get a nice Denon or Onkyo AVR with amplification and more advanced Audyssey features like Dynamic EQ and Dynamic Volume.  It doesn't seem cost effective at this point.

[candycane]

That VST is pretty much what I had in mind.  It is obviously priced from a "value-added" perspective for the professional market.  I agree at its current price it would not be viable for consumers.  Perhaps you thought of this already, but would the makers be receptive to disabling a feature or two (features only of value to a pro dealing with their studio needs) and offering it for a price more in line with a consumer product and more in line with its value-add compared to (free) Room EQ Wizard or room correction built into an AV Receiver?   Disable the pro-only features, so little or no marketing channel conflict and more money for them.  Or tie it into MC so that it can't be used without MC (so that audio pros don't buy this instead of the existing VST for their studios).

If IK can't or won't play ball because of Audyssey licensing issues or lack of fit with their business, perhaps chat with Audyssey directly for such a thing.  

It feels like there is space for a win-win (that's a fact-free assessment, but I'm an optimist), if IK or Audyssey are hungry to grow revenues and a few features can be disabled to provide the right marketing channel fit.

[cncb]

That VST is pretty much what I had in mind.  It is obviously priced from a "value-added" perspective for the professional market.  I agree at its current price it would not be viable for consumers.  Perhaps you thought of this already, but would the makers be receptive to disabling a feature or two (features only of value to a pro dealing with their studio needs) and offering it for a price more in line with a consumer product and more in line with its value-add compared to (free) Room EQ Wizard or room correction built into an AV Receiver?   Disable the pro-only features, so little or no marketing channel conflict and more money for them.

Reading about it I don't see anything that would be a "pro" feature that they could take out to reduce the price.  It looks like the same thing you get in an AVR (minus Dynamic EQ & Volume) so it seems that it is just over-priced.  The microphone does look more "professional" so maybe they could supply a lower-grade mic and reduce the price...

[Matt]

We've done a lot of work on Room Correction, Bass Management, and the related functionality during v15.

The only processing I would like that isn't there currently is per-channel equalization and volume-dependent equalization.

A microphone to calibrate the system automatically would also be neat.

[HTPC4ME]

A microphone to calibrate the system automatically would also be neat.

+1

[glynor]

A microphone to calibrate the system automatically would also be neat.

+2

It might be tough if you didn't actually sell the microphone yourselves.  Using "generic" mics would be awesome, but would make it impossible to profile the mic for use.

[Scolex]

A microphone to calibrate the system automatically would also be neat.

+point5
I can only give it a half a point cause with out real time management I find the calibrators a gimmick or for people that either can't or don't want to do it manually. I have a Yamaha receiver with YPAO and actually prefer the sound I got from setting it by ear.
Based on the quality of MC I am sure if you designed something it would work very well and would be loaded with features.

[cncb]

Based on the quality of MC I am sure if you designed something it would work very well and would be loaded with features.

There's no question that the guys at JRiver are very smart but I have to question the feasibility of them adding this.  I think it took years of research and development for the likes of Audyssey, Pioneer, Dolby, etc. to develop their room EQ and volume control systems so it would seem unlikely for them to easily add something as effective to MC...

[llafriel]

How about this tool:
http://drc-fir.sourceforge.net/
Last time I checked (some years ago), it used a microphone for measuring room response. Correction for both time and amplitude. It generates fir filters for convolving. I think it worked with foobar with a convolver plugin. Maybe there is an convolver plugin for MC already?

[Scolex]

There's no question that the guys at JRiver are very smart but I have to question the feasibility of them adding this.  I think it took years of research and development for the likes of Audyssey, Pioneer, Dolby, etc. to develop their room EQ and volume control systems so it would seem unlikely for them to easily add something as effective to MC...

They are all developing the technologies and/or are working in the hardware realm along with some doing studies of the aural perceptions of acoustics. Those require much more R&D than a software only solution. The basis is already in MC as it has time shift, equalization, amplitude analysis, etc. capabilities. They would need to create a multi-channel recording with varying frequencies and channel/s or create a software based signal generator that could run scripts/batches. Use a program that compares the returned recording to the base. To make it more accurate they would need to either sell microphones that are profiled or a small speaker that has been profiled and could be used to profile the end user supplied mic. Believe it or not headphones are great for profiling a mic because they have such a flat frequency response.

[MerlinWerks]

I recently picked up a minidsp and when coupled with Room EQ Wizard which is a very sophisticated measurement freeware package it should make for some fun times ahead, well for audio geeks anyway. I was already familiar with REW from my speaker building hobby and already have the hardware for a measurement rig including a calibrated mic. In addition to making manual adjustments, REW added an Auto-EQ feature which will determine the biquad coefficients for the required filters and export them in a format that can be imported directly into the minidsp hardware. Minidsp is a relatively new company and constantly working to improve the function and usability of their products, incorporating a lot of the feedback they've received from the DIY community. I know their collaboration with the author of REW was a deliberate effort and I got the impression they would be interested in partnerships with other companies.

[candycane]

+1 for the REW/miniDSP solution.  That seems to have the desired combination of capability, cost, and desire of the developers to integrate something with MC.  I hope J River gives the miniDSP folks a call to see if something can be worked out.  I can't tell exactly what capabilites this offers beyond what's already in MC, but REW is extremely capable.  And if there are certain capabilities that are not already in the miniDSP/REW combo to make this enough of an advance over what's already in MC, it sounds like the miniDSP and REW develoeprs would be open to a quation like "We'd need this kind of additional capability to make this worth it our MC customers.  Can you do it?"

I think the potential exists for something that, with a default config, can produce something very good, and also have options for tweakers to do what they do.  I think this is in line with a philosophy I think aligns with J river: a product with both ease-of-use and depth of capability to appeal to demanding music lovers with relatively little time to experiment as well as hobbyists.

This is neat stuff!

[mojave]

I also think that REW/miniDSP is a great solution. Here is a good article on it for those interested:  Subwoofer equalization and integration with the miniDSP 2×4.

The hardware portion of the miniDSP is only of benefit since we can't EQ with MC. If MC could perform the same functions as the miniDSP software, then we could use our soundcard's outputs (for those that use analog outputs) and wouldn't need the miniDSP hardware.

Here are a couple of solutions for MC to work on:

1.  MC needs to allow REW to be used a source. This has been requested here before. One could then use their own microphone with REW and take measurements of the changes made within DSP Studio (EQ, Room Correction, etc.). You currently can't easily measure any changes made within DSP Studio.

2.  MC could work with the miniDSP developers to integrate their software into the DSP Studio. MiniDSP has already stated in their forum that they won't be making their software into a VST plugin. However, maybe MC could get a license for the software and make it integrate into MC. The software only costs $10 as it is so it shouldn't add a lot to the cost of MC. The REW filters could be exported into the miniDSP software within DSP Studio.

2.  MC could develop their own parametric EQ with similar capabilities to the miniDSP software. They could work with John Mulcahy (the developer of REW) to import its filters into their EQ. Since John provides REW for free, maybe MC should purchase REW as their measurement software and sell it as a separate program and integrate it into MC. There is a large user base of REW and this move would introduce them to MC.

[candycane]

Another idea to lower the hurdle to make this attractive to J River and users:

A large part of the value and cost will be wrapped up in the calibrated microphone needed for the auto-EQ setup.  Perhaps we create a board for a "microphone swap" to allow those who have tuned their setup and no longer want or need the microphone to sell, loan, or rent their microphone to others.  The higher the cost of the microphone relative to the whole cost, the greater potential value this may have.

Or something similar to lower the cost barrier without sacrificing value. 

[mojave]

I had my Behringer EMC8000 calibrated by Cross-Spectrum. They sell already calibrated microphones for $70 or $80, depending on the model. However, you also need a preamp which increases the cost, too. I don't think people want to trade around microphones and preamps.

The Dayton OmniMic is a neat measurement system with a calibrated USB microphone. It is fairly expensive ($298) but easy to use from what I have read at AVSForum. I would love to be able to use a mic like that with MC. Besides selling through Parts Express, Dayton does sell many products to OEMs. Maybe JRiver could incorporate the mic/measurement software into MC and sell it as an added product.

[JimH]

Maybe we could rent them out for $25 or $30.

There are a lot of good ideas here.  Thanks.

[mojave]

With a little research, I found that the Dayton OmniMic software is developed by Bill Waslo. He also owns Liberty Instruments and developed the Praxis measurement software. He posts at AVSForum as bwaslo. He would be a great resource for integrating measurement/eq software into MC.

[Matt]

Would a good start be a parametric equalization DSP?

It would allow any number of rules, and rules could apply to specific channels or to all channels.

[mojave]

Yes, that would be a great start! If it could import the filters from Room Equalization Wizard that would be even better.

I would suggest the following:

1. A frequency range from 5 Hz to 20 kHz
2. Bandwidth from .01 to 2 should be sufficient
3. Gain of +/- 15dB

[Matt]

Yes, that would be a great start! If it could import the filters from Room Equalization Wizard that would be even better.

I would suggest the following:

1. A frequency range from 5 Hz to 20 kHz
2. Bandwidth from .01 to 2 should be sufficient
3. Gain of +/- 15dB

Do you know, when they make the graph showing what a parametric equalizer will do to the frequency, do they just use a formula, or do they actually run some pink noise through the actual filter and do FFT on the result?  It seems like the latter would look worse, but be more realistic, especially if there were multiple equalization steps.

[MerlinWerks]

Do you know, when they make the graph showing what a parametric equalizer will do to the frequency, do they just use a formula, or do they actually run some pink noise through the actual filter and do FFT on the result?  It seems like the latter would look worse, but be more realistic, especially if there were multiple equalization steps.

If you are referring to REW, I would say it's the former. Once you make a measurement, you select the EQ filters page and the graph of the measurement you made is presented there. At that point you can manually adjust the filters yourself (gain, frequency and Q) or you can have REW automatically determine those values based on criteria you provide. For example you can specify the frequency range you want it to focus on, say 40hz to 1000hz and a target level say 75 db SPL and that you want it to be within 3 db of that level. REW then runs through several iterations of algorithms (I'm assuming) to determine the best filter settings to accomplish that goal or at least come as close as possible. You can then export those settings to your EQ hardware, miniDSP in my case or simply manually adjust your EQ if it's not hardware that REW supports directly. This is a very simplistic explanation since that matches my understanding at this point   But I do believe there are more advanced criteria that you can specify if you know what you are doing  

[mojave]

Do you know, when they make the graph showing what a parametric equalizer will do to the frequency, do they just use a formula, or do they actually run some pink noise through the actual filter and do FFT on the result?  It seems like the latter would look worse, but be more realistic, especially if there were multiple equalization steps.

Actually you can do both. You first are able to see the original response. Then REW will generate filters to smooth that response. You can then see the affect of the filters and what the filters look like. Finally, you can run sweeps with your system to see if it now measures better after adding the filters to your EQ device or software. Because you can't directly use REW's output with MC, you can however use the REW signal generator to create a pink noise sweep that can be played in MC and analyzed with REW's RTA.

[BradC]

What I would really like to see in MC is the ability to route channels for use in digital crossovers for multiway speakers.

That is, I need to be able to apply different VST filters to 8 output channels that are fed the stereo input signal. (11 channels for surround recordings).

At present there is only a 1 to 1 mapping, I need a 1 to many mapping.

A VST plugin such as pristine space can take 2 channels in and output 8 channels, but in MC, I have no way to direct where the 8 output channels go, nor run multiple instances of pristine space

[mojave]

Herb at Cross Spectrum Laboratories has checked the calibration on several of the Dayton Audio EMM-6 microphones and found that these are fairly accurate. Each one has a calibration file that can be downloaded as a txt file. Of course they still need a preamp with phantom power, but this is a fairly economical way to get accurate measurements for room correction.

[Mr. Tuesdays]

A lot of folks use the Panasonic mic capsules to build their own measurement mics.  A rather inexpensive option.
I got to see the Dayton USB system prototype in use in Ohio.  Bill Waslo was there with it.  Very nice and easy to use, but not cheap.  Of course you are also paying for the very good software included.

Most soundcards have a powered mic input that can be used with the Panasonic and similar capsules.  Of course you would still have to build your own, and many folks can't solder.  Finding an inexpensive off the shelf mic ready to go would be key.

It's a cool idea.

[dumpster]

+1 for:

- a REW and microphone combo (perhaps with Dayton/Liberty Instruments) for auto-EQ integrated with MC
- start with parametric (PEQ), and then expand to IIR and FIR filters for auto-EQ (but please don't start with PEQ in a tool that can't do IIR or FIR filters)
- offer a rental/resale/loan model to deal with the one-time and infrequent (but critical) need for the microphone and room correction in general
- consider also becoming a reseller for acoustic room treatments (the most effective room correction typically requires physical treatment as well as electronic compensation, and while some acoustic treatment manufacturers are quite snobby about EQ, some could be quite helpful by participating in a discussion board in interpreting analysis results and offering recommendations)

It would also be super clever to use this to calculate the latency setting for multi-room sync of linked zones (generate an audio pulse from a PC in one room, place the mic connected to a PC in another room, and synch the PC clocks so that the mic can audibly determine the total system latency).  But I admit this last idea is just a neat toy for what is already a decent enough method in MC.

[Mbare]

I use Audiolense as my room-correction-tool and that works splendidly. Not too expensive, either. Easy to set up, easy to use and lots of stuff to play with it, if you like that kind of thing. As far as I know, J. Media has its own convolver-thingy, so supposedly you can use the correctionfiles from Audiolense straight into J. Media.

[ruze]

Maybe we could rent them out for $25 or $30.

There are a lot of good ideas here.  Thanks.

This is an awesome idea.  Please announce if you folks ever think about doing this!