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[stewart_pk]

Hi, I believe I have read that JRSS Mixing lowers the LFE (.1) channel by 10db because it expects it to be calibrated at +10db in A/V Receivers/Processors.
If this is the case then when down-mixing to channels without a dedicated LFE (.1) channel (i.e. 2.0, 4.0, 5.0, 7.0) should one be raising the LFE (.1) channel by 10db in DSP Studio ---> Parametric Equalizer 1 or 2?

[franswilco]

Does this affect Volume Leveling as well?

[mattkhan]

Hi, I believe I have read that JRSS Mixing lowers the LFE (.1) channel by 10db because it expects it to be calibrated at +10db in A/V Receivers/Processors.

are you referring to https://wiki.jriver.com/index.php/Room_Correction#Bass_Management_In_Action ? if so, this specifically refers to the room correction module

If this is the case then when down-mixing to channels without a dedicated LFE (.1) channel (i.e. 2.0, 4.0, 5.0, 7.0) should one be raising the LFE (.1) channel by 10db in DSP Studio ---> Parametric Equalizer 1 or 2?

I don't know what you mean, jrss downmixing happens before any PEQ can be applied so the LFE channel (which is an input channel) no longer exists by this point.

https://yabb.jriver.com/interact/index.php?topic=79282.0 gives some idea of what happens though doesn't state the exact mix parameters used. I imagine you could work this out if you were so inclined by measuring it yourself (see https://wiki.jriver.com/index.php/Verifying_DSP_Studio for details).

[RD James]

I would expect it to be the other way around so that Media Center would add 10dB to the LFE channel when downmixing (well, reduce all other channels by 10dB), as most AVRs do not apply a +10dB boost to LFE if they are receiving a PCM signal.

[stewart_pk]

I would expect it to be the other way around so that Media Center would add 10dB to the LFE channel when downmixing (well, reduce all other channels by 10dB), as most AVRs do not apply a +10dB boost to LFE if they are receiving a PCM signal.

I don't know what you mean, jrss downmixing happens before any PEQ can be applied so the LFE channel (which is an input channel) no longer exists by this point.

Thinking about this a bit more, in regards to down-mixing I think JRiver should leave it alone (+0db) or thereabouts because there's no way to adjust it afterwards as PEQ happens after downmixing with JRSS.
I think I'd like to see a new feature in Room Correction ---> Bass Management ---> Routing called Move bass to Left and Right for my 4.0 setup where my rears are small and my fronts are very large.

[RD James]

Thinking about this a bit more, in regards to down-mixing I think JRiver should leave it alone (+0db) or thereabouts because there's no way to adjust it afterwards as PEQ happens after downmixing with JRSS.

Dolby/DTS formats are encoded with LFE at -10dB and need a +10dB correction to restore the correct level.
If Media Center is converting to PCM rather than bitstreaming, it should be reducing the volume of all other channels by 10dB for a correct mix, as AVRs will not be boosting the LFE channel by 10dB if they receive a PCM signal rather than an AC3/DTS signal.

[stewart_pk]

Dolby/DTS formats are encoded with LFE at -10dB and need a +10dB correction to restore the correct level.
If Media Center is converting to PCM rather than bitstreaming, it should be reducing the volume of all other channels by 10dB for a correct mix, as AVRs will not be boosting the LFE channel by 10dB if they receive a PCM signal rather than an AC3/DTS signal.

The way I see it for PCM yes and no.

Yes if you're down-mixing to X.0 channels and want the LFE (.1) included then JRiver should be increasing the LFE by 10db or decreasing all other X channels by 10db.

If the LFE is being sent as a dedicated LFE (.1) i.e. X.1 channels then JRiver should be leaving the .1 alone relative to the X channels, because it's expected that the AVR/Processor will have LFE boosted by 10db from calibration. That is what I gather from: https://wiki.jriver.com/index.php/Room_Correction#Bass_Management_In_Action

[mattkhan]

because it's expected that the AVR/Processor will have

note that this is a reverse engineering exercise, i.e. I measured the stated behaviour and infer that this means jriver expects downstream to do something to make the end to end correct.

It does *not* mean that this expectation (of MC) is correct nor that mainstream AVPs do typically behave this way. I don't recall the answer to that tbh.

[RD James]

It should be a safe assumption that PCM is not going to have +10dB applied because that AVR would be playing back any multichannel PCM source incorrectly if it does.
So long as you are not mixing PCM and bitstreaming, it shouldn't matter either way really, if you calibrate the levels using Media Center as the source.