Film-Tech Forum ARCHIVE: What is the "Front Wide Channel" in A/V Home Theatre jargon?

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Posted by Frank Angel (Member # 248) on 12-03-2019, 08:28 PM:

I am stuck with a Marantz AV7704 component (two of them, actually) in our small screening rooms; Marantz calls the unit an A/V "PreTuner." I guess that's because it has a tuner and also something we used to call a preamp. In a booth it would be the equiv of a Cinema Processor.

Anyway, it is a pretty sophisticated piece of equipment that handles everything from 5.1 to Dolby Atmos and DTS's porno version of object-based audio, DTS:X. Unfortunately this Marantz is loaded with all kinds of stuff that manipulates audio and introduces a myriad of "options" to allow the half-wit consumer to jack around the sound. Even the speaker setup and amplifier channels are not identical to standard cinema configurations.

My big concern is about this thing they call the Front Wide Channel. Their manual diagram shows that to be an another side wall speaker in addition to the side wall surround speakers. WTF? In standard Dolby cinema configuration, side surrounds -- no matter how many of them, on the side wall, all of them reproduce the same Left or Right channels output.

The Marantz unit seems to add this extra side channel (derived from what, I don't know). They give no indication of what's the origin of that channel's audio -- is it the surround channel being somehow processed and mixed with the front Left or Right channels? Who knows what they are doing. While their manual is lengthy and otherwise pretty detailed and well written, they don't explain what this channel in much detail.

Our surrounds in these screening rooms consist of two JBL surround speakers on each side wall. According to Marantz, in that configuration they should be split; one should be the Front Wide channel and the other should be using the Surround channel. In real life, the two side speakers should be voicing the same channel audio -- Left Surround or Right Surround.

If anyone has any familiarity with this terminology and/or directly with the Marantz processor (AV7704 or similar) and can tell me what is the purpose of this non-standard channel (evidently it is used in all multichannel formats), I'd be happy to hear it.

My instinct is to just ignore it and do what would be done in any cinema, make the two Left and Right surround speakers voice the same audio. I don't think the sound designers and the sound mixers of the movies we will play need some joker at Marantz to add his own nonsense to the mix. If the filmmakers wanted the mix to sound WIDE...they would have mixed it that way. I'm just sayin.

Damn these consumer products.

Posted by Alan Gouger (Member # 543) on 12-03-2019, 09:46 PM:

I also have the Marantz, I tried the front wide spkrs and decided to not use them. If using the FW they are not always active only durring certain atmos mixes. Most of the time they are silent. If opting for the front wide spkrs then you lose the surround back, choose one or the other.

Posted by Marcel Birgelen (Member # 6801) on 12-03-2019, 09:58 PM:

The "Front Wide" speakers are supposed to fill the "gap" between the sides and the front speakers.

Their usage is dependent on the engine running on the AVR:

Audyssey Audio Enhancement crapola: A matrix mix of the front stage speakers and the left and right surround with some reverb added.

DTS:NeuralX: The same as with Audyssey minus the extra reverb.

DTS:X and (consumer) Atmos: Objects that end up at that location.

If you have to give up 7.1 standard channels for them, your decision should be clear. Also, if you want to simulate the average cinema as closely as possible, don't use them either or only for object based mixes.

Posted by Frank Angel (Member # 248) on 12-03-2019, 10:00 PM:

Thanks Alan; in fact, that's what I just decided to do after futzing around with a Spears & Munsil disc right after the post.
The audio test section showed me that on both 5.1 and 7.1 formats (the only two we are are set-up for), indeed nothing does come out of the Wide channel. Since our two side wall speakers have their own amps, I will simply feed both of the same Surround Channel outputs.

I am at least heartened to hear nothing coming out of that channel; at least it doesn't contain some reverb nonsense or phase shift mix to create some pseudo "width" bs that I have noted on some other consumer products, because I really like the Marantz.

Posted by Marcel Birgelen (Member # 6801) on 12-09-2019, 06:47 PM:

quote: Frank Angel
I am at least heartened to hear nothing coming out of that channel; at least it doesn't contain some reverb nonsense or phase shift mix to create some pseudo "width" bs that I have noted on some other consumer products, because I really like the Marantz.

Most mid-range and higher range consumer products are essentially just running Audyssey's MultiEQ software stack. Whether or not it is doing "pseudo phase shift reverb nonsense" depends a lot on the settings of MultiEQ.

Posted by Frank Angel (Member # 248) on 12-10-2019, 01:16 PM:

Studios sure went ape-shit to make sure their content couldn't be copied; I say that HDCP control chip should block consumer products from mucking around with audio formats as well. 5.1, 7.1 Auro, Atmos, etc., or any other sound configuration/processing that the FILMMAKER uses now or in the future for the sound design should be enforced; all other pseudo nonsense should be disabled. And while we are at it, it should also block displays from being able to play content in aspect ratios other than the native AR in which the image was authored. If the display device tries to stretch the image to eliminate LB bars, the chip should shut it down and make the stupid End User have to wait an hour before it will turn on again.

Now THOSE are HDCP functions I can get behind!

Posted by Harold Hallikainen (Member # 5405) on 12-10-2019, 02:11 PM:

There is a document from Dolby that includes Left Wide. See https://developer.dolby.com/globalassets/technology/atmos/additional-channels-for-immersive-audio.pdf .

Harold

Posted by Helmut Maripuu (Member # 2281) on 12-10-2019, 02:55 PM:

My friends think I have a great sound in my home theater. They ask me whats the brand of my amplifier I use. I explain to my friends that I have a Panasonic Bl player with 7.1 analog out, connected directly to my Behringe power amplifier and no preamplifier.

Posted by Frank Angel (Member # 248) on 12-11-2019, 01:30 PM:

Harold, thanks for the link. That Dolby document is talking about a consumer Atmos-type configuration which, if I understand it correctly, is taking object-based elements and placing them into groups so they can be played back in channel-based consumer system. Problem with that is, as Alan confirmed, that will only work if there is a Atmos track on the BluRay. If there isn't, you are giving up a stereo amp and Left and Right side speakers which will be doing nothing most of the time. Based on what Alan posted, we did testing and we couldn't find any playback where that Front Wide channel had any audio playing from it at all; it will only play audio if there it is an Atmos disc. I would say 98% of our disc library only has straight 5.1, or to a lesser extent, 7.1 content and we have more DVDs than BluRays; the library was started in the era of Laserdisc so you can imagine in a library of a few thousand discs, how few are BluRay and of those how many might actually contain Atmos tracks!

So it makes much or sense for me to use that amplifier and the side wall speakers to duplicate the Left and Right Side Surrounds (we have two speakers on each side wall, and split surrounds in the rear) than connect it to the Front Wide channel.

Posted by Daniel Schulz (Member # 1881) on 12-11-2019, 08:20 PM:

quote: Marcel Birgelen
DTS:NeuralX: The same as with Audyssey minus the extra reverb.

DTS:X and (consumer) Atmos: Objects that end up at that location.

One thing I find interesting is that while DTS Neural:X utilizes the Front Wides, the Dolby Surround Upmixer (which upmixes 2.0, 5.1 and 7.1 content into the extended-channel Atmos layouts) does not - Dolby felt that steering sounds into the Front Wides mucked with the front soundstage too much.

Anyway, I agree with the other posters here - Front Wides are a nice-to-have but only as a next step after you've already got at least 7.1.4.

Posted by Sean McKinnon (Member # 612) on 12-14-2019, 05:51 PM:

In the Cinema version of Atmos there are wide left and right surrounds that are additional and not part of the 5.1/7.1 arrays.

Posted by Jesse Skeen (Member # 586) on 12-14-2019, 10:40 PM:

I've been well-versed in sound for decades, but admit all this new-fangled stuff has confused me. At home I have a Marantz system with Atmos, with just two "height" speakers as that's all I have room for. It seems four is the ideal but I'd have to add another amp for those.

I have ONE movie on disc- the 3D remake of "My Bloody Valentine", which when bitstreamed shows it has left and right "front wide" channels. If I output it as PCM (thus enabling the neato menu sound effects) it outputs in standard 7.1 format which I'm more familiar with, faking extra channels for the Atmos speakers. I still don't know what the right way to play that is. I know that with Atmos and DTSX you have to make sure the audio is bitstreamed, otherwise you lose the extra info for those. Waiting for the next format to have floor speakers.