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[hulkss]

I am considering moving from a rack full of audio/video gear to an HTPC. It looks like Windows 7, Media Center, and Audiolense software may meet my needs.
Primary requirements:
1. Blu-ray disk playback in the HTPC
2. Support for 7.1 audio with digital loudspeaker crossover filters and audio correction filters from Audiolense.
left, center, and right speakers are tri-amplified, 2 surround speakers, 2 rear speakers, 3 subwoofers for a total of 16 separately amplified audio channels
3. Time delay of video,  Audiolense processing causes a significant audio time delay requiring the video to be delayed as well
4. Quality up scaling of 2 channel audio files to 7.1
5. Playback of other HDMI video-audio sources connected to the HTPC
6. Considering Motu 24I/O audio hardware
7. Video hardware?

Can the above be accomplished?

[Trumpetguy]

I can not see any reason why you shouldn't! The only exception would be if you want too many audio channels, but I believe MC can to 16 and more.

I run a similar system already and can verify that MC is the ONLY software I have tested that can do items 1, 2, 3, 4, 5 with no fuzz, with e.g. ASIO playback of all audio regardless of source (cd, dvd, bd, files on harddrive etc). Audiolense filters with ConvolverVST works just fine. With the recent addition of the video delay function A/V sync is no longer a problem (one exception - not working well for optical dvd playback because of MS video decoder). After Red October, video codec issues are more or less gone.

I would guess you would use digital attenuation (volume control) and connect directly to your humongous power amplifier rack? What DAC are you considering (is it the Motu)?

What do you mean by video hardware? Video card? Or do you have other requirements like external scalers and such?

EDIT: removed ref to item 5. I have of course not connected any external components via hdmi either as nevcariel points out is not possible just yet.

[Hendrik]

I'm not aware of any components that actually allow HDMI *input* in a sane maner. (regarding point 5).
I'm afraid you cannot replace a AV-Receiver with a HTPC just yet. What its really designed to replace is the media sources, iow. the blu-ray player, the network player, maybe even the gaming console, and then using an external receiver for the HDMI management.

[BradC]

Yes you can do all of those things. For point 5, how many sources do you have?
If only another one or two, can you use secondary video inputs and use an audio in on the motu?

I have pretty much the same requirements. However, I use a RME firface 800 and acourate software.

You will also need anydvd hd for the playbck of bluray in MC and most likely, Plogue Bidule for channel mapping for your active speakers.
The latest version of Plogue Bidule VST plugin now works in MC.

[mojave]

You can actually do active speakers now with JRiver's Parametric EQ DSP Plugin. It allows you to map/mix channels, adjust delay and gain on each channel, add high and low pass filters with varying slopes, and add parametric EQ to individual drivers, a speaker, or groups of speakers. The mix channels feature allows you to add, copy, move or swap channels

There are several things you can't do that are available/easier in Audiolense. You can't send sweeps or tests tones through JRiver using Room Equalization Wizard (REW) or other measuring software. You only get one type of filter (no choices for digital representations of Bessel, Butterworth, Linkwitz-Riley filters), and you can only perform parametric equalization, but not not room correction like Audiolense or Audyssey. Regarding room correction, there are varying opinions as to its effectiveness.

I am using a Steinberg MR816x as my audio device. For two channel listening I currently use Parametric EQ to copy the left channel to the center channel (output 3) and the right channel to the LFE channel (output 4). I have my left subwoofer connected to output 3 and my right subwoofer connected to output 4. I use room correction to apply a 60 Hz high pass filter at 12 dB/octave to my mains. I use Parametric EQ to apply a 100 Hz low pass filter at 48 dB/octave on the subwoofers. This gives each subwoofer a single channel and from 60 Hz to 100 Hz both the subs and mains overlap. Any gain in this area can easily be pulled down using a parametric EQ filter.

When using Analyzer or other spectrum analyzer to view two channel audio, the left and right track are always slightly different in the bass frequencies. When these are combined in a single LFE track like is done with most bass management, I don't think it sounds as good as when a sub gets just the left or just the right channel. I've done a lot of listening switching back forth and first started investigating this when I had my Behringer DCX2496. I am essentially running 3-way mains with an active crossover for the subwoofer to woofer and a passive crossover for the woofer to tweeter.

[mojave]

Here is a thread at HomeTheaterShack that has a nice youtube video showing how to create filters in REW and use them in a Digital Audio Workstation (DAW). This translates very nicely to using the filters in JRiver and shows how to get before and after measurements using REW.

[hulkss]

I would guess you would use digital attenuation (volume control) and connect directly to your humongous power amplifier rack?
Yes, that would seem right

What DAC are you considering (is it the Motu)?
Thinking about Motu, or RME, or ?

What do you mean by video hardware? Video card? Or do you have other requirements like external scalers and such?
Just was wondering how to get HDMI input to HTPC

[hulkss]

I'm not aware of any components that actually allow HDMI *input* in a sane maner. (regarding point 5).
I'm afraid you cannot replace a AV-Receiver with a HTPC just yet.

My objective is to replace everything in the rack but the power amplifiers, game console, and satellite receiver

[hulkss]

For point 5, how many sources do you have?
A game console and satellite receiver.

If only another one or two, can you use secondary video inputs and use an audio in on the motu?
I would like to bring digital audio and video into the HTPC and process it the same as if I was using a source internal to the HTPC (Blu-ray or audio file)

You will also need anydvd hd for the playbck of bluray in MC and most likely, Plogue Bidule for channel mapping for your active speakers.
Channel mapping is not available in MC or Audiolense?

[hulkss]

Regarding room correction, there are varying opinions as to its effectiveness.

Yes, room correction is a can of worms. Loudspeaker correction, however, is possible. I would like to correct the response of the active speakers when measured in the near field. Then measure in the seats to do "adjustments" to a preferred "house curve".

[BradC]

The linear phase room correction of audiolense and acourate are far more sophisticated, and have far more computation power available, than the automated processes of Audyssey etc.

I get very good results with room correction from acourate.

Mojave, the OP expects to use 16 channels for active and surround speakers. Each channel will have a filter applied via convolution. The VST plugins Convolver or pristine audio space are typically used. Hence multiple instances of the convolver plugin will be required.
I still cannot see how one would map different channels to different instances of convolver plugins within JRiver.
If this can be done now, could you please explain how.

I am not aware of any way that a HDMI in could be processed and output through the video card on a PC at the moment.

You could however get a solution by using multiple zones for the audio in jriver and using multiple video inputs on your display. Otherwise you would likely need an external video processor (ie scaler or AV receiver) to achieve video processing of all inputs.

[BradC]

Hi

I have had a closer look at audiolense. It suggests users use convolver for convolution. Convolver can apparently do channel mapping and crossovers with a config file.

I do not know if this channel mapping works correctly in jriver, as I have not tested it, but it may work.

[Trumpetguy]

For Audiolense, I think ConvolverVST in MC DSP studio os the best and most stable solution. It excludes sources not routed through MC, though.
Audiolense is excellent for channel mapping.

You should take a look at the LynxTwo or Aurora series of Lynx DACs. I use an Aurora8 for my 7.1 setup, but you can expand number of channels according to the initial size of your bank account. Pros: Excellent audio quality, stability, and driver development, stability and configurability. Cons: Using the superior Aurora world clock forces me out of my sofa every time I need to change sample rate. LynxTwo PCI cards have automatic switching.

[mojave]

Mojave, the OP expects to use 16 channels for active and surround speakers. Each channel will have a filter applied via convolution. The VST plugins Convolver or pristine audio space are typically used. Hence multiple instances of the convolver plugin will be required.
I still cannot see how one would map different channels to different instances of convolver plugins within JRiver.
If this can be done now, could you please explain how.

The context of my post was using JRiver all by itself for active crossovers. Many use the Behringer DCX2496, miniDSP, or something similar for active crossovers. JRiver now allows you to duplicate this with its own Parametric EQ. You can do nearfield EQing of the actual speaker using REW and input the filters into JRiver. One should be able to get a speaker to measure +/- 2dB before any room interaction.

I don't think the channel mapping would work with multiple convolver plugins. JRiver doesn't support multiple instances of a plugin, which is why you recommend Plogue Bidule.

[JimH]

hulkss

You can quote a user's reply like this:

[quote ]
User said this
[/quote ]

but the space in each quote above causes it not to work, so if you remove the space, it looks like this:

User said this

[Trumpetguy]

The context of my post was using JRiver all by itself for active crossovers. Many use the Behringer DCX2496, miniDSP, or something similar for active crossovers. JRiver now allows you to duplicate this with its own Parametric EQ. You can do nearfield EQing of the actual speaker using REW and input the filters into JRiver. One should be able to get a speaker to measure +/- 2dB before any room interaction.

I don't think the channel mapping would work with multiple convolver plugins. JRiver doesn't support multiple instances of a plugin, which is why you recommend Plogue Bidule.

I agree with BradC, if hulkss plans to use Audiolense, this excels any MC crossover capabilities (even if MC itself is a good thing if you don't want to spend money on Audiolense. The calibrated microphone you would need anyway).

[hulkss]

For Audiolense, I think ConvolverVST in MC DSP studio os the best and most stable solution. It excludes sources not routed through MC, though.
Audiolense is excellent for channel mapping.

You should take a look at the LynxTwo or Aurora series of Lynx DACs. I use an Aurora8 for my 7.1 setup, but you can expand number of channels according to the initial size of your bank account. Pros: Excellent audio quality, stability, and driver development, stability and configurability. Cons: Using the superior Aurora world clock forces me out of my sofa every time I need to change sample rate. LynxTwo PCI cards have automatic switching.

Now planning to use the Lynx Aurora 16-VT with LT-USB interface card to HTPC USB 2.0. No PCI audio card needed. VT version of Aurora has increased output to eliminate the need for preamplifiers. HTPC under construction.

[nwboater]

Does the Lynx Aurora 16-VT now do automatic sample rate switching? If not I would find it quite a nuisance to have to manually change sample rates for different material.

Rod

[mojave]

This will be a great system! Please keep us updated.

[Trumpetguy]

Does the Lynx Aurora 16-VT now do automatic sample rate switching? If not I would find it quite a nuisance to have to manually change sample rates for different material.

Rod

It DO looks very much the same as my Aurora 8, with the same manual sample rate switch. My limited understanding is that the VT version is he same as the Aurora 16 (and 8, but with twice the no of channels), but with variable trim on output voltage. The Aurora8 and 16 also has two different trims (+4dBu and -10dBV), though, but not manually variable pots.

[Trumpetguy]

Now planning to use the Lynx Aurora 16-VT with LT-USB interface card to HTPC USB 2.0. No PCI audio card needed. VT version of Aurora has increased output to eliminate the need for preamplifiers. HTPC under construction.

Right, it would be as if I was using my Aurora 8 with firewire connection I guess. In my case I use the Aurora as an expansion from previous LynxTwo setup, so it involves PCI cards in addition.

But it works really well to skip the pre-amp and use digital attenuation directly into the power amps.