Redirecting LFE to Mains

[Nimby]

Hi

It's difficult to know where to place this question. Mods please feel free to redirect this to a more suitable forum.

Q: Where in an AV system can one redirect the LFE channel to the Main speakers?

Is this usually done at the DVDP or is it normally a task for an AV Processor or AV Receiver?

Is it even be possible in my hybrid Naim stereo/ Behringer EP2500 dual mono IB 4.0 system? (I'm using a Yamaha DSP E800 processor for the Rears)

The front speaker/sub system presently runs on the Mains signal. Splitting between the stereo speakers and 4 x 15" IB sub using a Behringer CX2310 active crossover @ ~80Hz.

I'd like to redirect the LFE channel to the Mains if possible. My (slightly fuzzy) understanding is that setting the Mains to "Large" (in the DVDP?) does not always redirect the LFE to the Mains. I have no real idea under what circumstances LFE is simply discarded or is actually redirected to the mains.

If there is more bass hidden in the LFE channel I'd really like to be able to hear it.

Any thoughts how I might achieve this please?

Thanks

 

[niceguy235uk]

As far as im aware this can be acheived but only with a av receiver.

If you set the fronts to large then the amp will output most of the LFE to the fronts as the amp sees that these can handle the lower freqs that the sub would generally output.

Another option is to set the amp (if its possible) to 'no sub' then that will also redirect lfe to the mains.

I could be wrong but its just a thought.

 

[Nimby]

Thanks

The trouble is I'm still not sure if the LFE is sent to the Mains when "no sub" is set in the DVDP and Mains to "Large".

As far as I'm aware the old E800 is only providing the rear channels as I'm using the DVDP as the processor since it sounds better than the Yamaha.

Centre is also set to off in the DVDP.

It looks as if I'm going to have to plough through the manuals again.

Just what I was hoping to avoid.

 

[joffy1780]

I would think if you have settings of 'no sub' the LFE from channels set to 'small' will be directed to those set to 'large'.
But if you have your fronts set to 'large' and the sub set to 'on',the fronts will receive their full range signal,but the LFE from other channels set to 'small' will be only sent to the sub.

 

[Nimby]

I would think if you have settings of 'no sub' the LFE from channels set to 'small' will be directed to those set to 'large'.
But if you have your fronts set to 'large' and the sub set to 'on',the fronts will receive their full range signal,but the LFE from other channels set to 'small' will be only sent to the sub.

Thanks.

The settings are "Large" mains. No sub. No centre. "Small" rears.

I wonder where the bass for the rear channels goes?

 

[joffy1780]

They would be directed to your mains in that case.

 

[niceguy235uk]

There is no LFE from any channel, including the rears.

The LFE channel has its own dedicated track on the dvd which is then sent straight to the sub.

However, if no sub is selected then the LFE will be passed, generally, to the mains.

 

[Nimby]

The NAD DVDP manual says nothing about bass redirection at all.

The Yamaha E800 manual is very thorough and talks about redirection of the bass from all other speakers being sent to the Mains when set to Large.

But no mention of "LFE" at all in either manual that I could see from scanning through.

Horror of horrors! I have had the audio Dynamic Range Compression set to on in the DVDP menu!

Possibly from new! I have no memory of ever setting it and had no idea what DRC meant anyway and it was hidden out of sight under "Others" in the DVD menu.

I only just discovered this from the manual! AAArrgghh!

 

[joffy1780]

I think what Nimby means is-where is everything below the crossover sent,e.g.if his crossover is set @ 80hz then anything under that,which would be sent to the rears,will be sent to the mains in this case.
But if he had his sub set to 'on' everything under 80hz from the rear channels would be sent to the sub.

 

[Nimby]

I'm afraid the crossover is irrelevant in this case. It is just an active crossover splitting the mains signal at 80Hz. It has no more effect on the 5.1 signals than a passive crossover in a normal mains speaker.

I had been reading the article below and this is where my confusion about LFE arose. It mentions that redirecting LFE is not always automatic. I hoped someone would be able to say under what circumstances LFE isn't redirected.

http://www.hometheaterhifi.com/volume_7_2/feature-article-misunderstood-lfe-channel-april-2000.html

 

[Jase]

Q: Where in an AV system can one redirect the LFE channel to the Main speakers?

Is this usually done at the DVDP or is it normally a task for an AV Processor or AV Receiver?

Can be either/or. Depends what bass management options they have. Some DVD players have very good bass management setup, others are limited. Personally, I leave all mine up to the AV Amp.

 

[Reiner]

I'm afraid the crossover is irrelevant in this case. It is just an active crossover splitting the mains signal at 80Hz. It has no more effect on the 5.1 signals than a passive crossover in a normal mains speaker.

I had been reading the article below and this is where my confusion about LFE arose. It mentions that redirecting LFE is not always automatic. I hoped someone would be able to say under what circumstances LFE isn't redirected.

http://www.hometheaterhifi.com/volume_7_2/feature-article-misunderstood-lfe-channel-april-2000.html

Usually the LFE is not redirected as there is no need for that, assuming a full setup (5 speakers + subwoofers). But if you don't have a subwoofer set 'Subwoofer' = 'NO' in the setup of the Yamaha, then the LFE will be redirected to the main/front speakers.

(Is it possible you confuse bass with LFE since the article mentions redirection only in reference to bass (not LFE)? As niceguy235uk mentioned the LFE has it's own dedicated track, the ".1" in 5.1)


Actually, how is the DVP connected to the Yamaha, via a digital connection (optical/coaxial) or analog (6xRCA/phono interconnects)?

 

[Nimby]

Usually the LFE is not redirected as there is no need for that, assuming a full setup (5 speakers + subwoofers). But if you don't have a subwoofer set 'Subwoofer' = 'NO' in the setup of the Yamaha, then the LFE will be redirected to the main/front speakers.

(Is it possible you confuse bass with LFE since the article mentions redirection only in reference to bass (not LFE)? As niceguy235uk mentioned the LFE has it's own dedicated track, the ".1" in 5.1)

how is the DVP connected to the Yamaha, via a digital connection (optical/coaxial) or analog (6xRCA/phono interconnects)?

I'm using 6 x RCA for what Yamaha call "6 Channel input".

I do of course have the option of a digital connection. I haven't tried.

Are there advantages to either connection type in the context of my system?

 

[Reiner]

I'm using 6 x RCA for what Yamaha call "6 Channel input".

I do of course have the option of a digital connection. I haven't tried.

That should be fine, I think the Yamaha treats the analog inputs in the same manner as the digital ones, so all the settings apply here, too. Actually I would leave everything to the amp, so at the DVDP you can just set all the speakers to large and activate the subwoofer (output).
AFAIK many DVDPs discard the LFE when you use the analog connections and select that you don't have a subwoofer.

Are there advantages to either connection type in the context of my system?

It usually depends on which equipment is better at the decoding (the DVD player or the AV amp/receiver), often it's just a matter of trying out and see what sounds best to you.
If you use SACD or DVD-A you often must use the analog connections, otherwise the digital connections offer the advantage of less cables.

 

[Nimby]

Thanks Reiner.

There is a clear audio advantage to the NADT533 used as processor over the Yamaha doing all the work. I just tried the digital coax audio connection but the sound quality really wasn't good enough.

I enjoyed films using the Naim 72/180 in stereo using only 2 channel analogue connections off the DVDP to the '72 for a couple of years. The sound quality left everything else I've ever heard for dead.

While I badly wanted surround sound for a "better" film experience I hated the sound quality of the AV receivers I'd heard. So I bought the used E800.

By using the NAD as processor and leaving the Yamaha to provide only the rear channels I retained the superb sound quality and I'm now enjoying basic surround sound.

Back to the LFE problem. I have set the Yamaha (as well as the NAD) to send all bass to the Large mains, small rears, no sub, no centre. Whether this has any effect when using the NAD as external processor I really don't know, yet.

 

[Knyght_byte]

iirc the LFE signal doesnt deal with very deep signals anyhow.....i could be wrong but i was under the impression it only handles something like 35-80hz freqs?

if sub set to off then this signal goes to the front left/right channels........its not a deep bass, more of a powerful bass signal thats designed to create a physical effect rather than a musical one.......ie when concrete crunches together in WOTW first tripod emergin scene.....

if you send it to the fronts, but have a device in the way thats splitting off freqs under 80hz then it should go to the sub anyhow.......if you set that crossover to say 50hz then some would still go to the fronts........the danger is if you have the LFE going to the fronts and they can hit lower freqs but are not well built speakers and are being underpowered amp wise then you could do damage to them easier as they are receiving a lot more signal than normal stereo music would give..........i ran a pair of wharfedales like this and they survived but they had reasonably long throw drivers and were powered sufficiently....

 

[Nimby]

An interesting post KB. Though I'm not sure you are right about the very deep bass in the LFE channel. It's hiding in there somewhere or a subwoofer would have an easy life running on LFE!

Even if you send all the bass to the front mains, provided they are floorstanders, then they should cope. They simply won't attempt to play what they can't reach down to. Just like any speaker capable of being run on fullrange material.

My understanding is that the LFE bass when redirected to the mains will be at the same level as the rest of the mains signal. So it shouldn't cause problems.

As you say; in my case it isn't a problem. Whether the greater clarity is the direct result of being physically relieved of bass duties. Or the removal of masking by the muddy bass. I'm not entirely sure. It's probably a bit of both.

 

[Jase]

For Dolby Digital the LFE channel can contain info from 3-120hz. It's up to the sound mixer as to what they actually include though.

 

[Reiner]

By using the NAD as processor and leaving the Yamaha to provide only the rear channels I retained the superb sound quality and I'm now enjoying basic surround sound.

Sounds like the best way to do it.

Back to the LFE problem. I have set the Yamaha (as well as the NAD) to send all bass to the Large mains, small rears, no sub, no centre. Whether this has any effect when using the NAD as external processor I really don't know, yet.

Hm, since you apply settings in the Yamaha and NAD they are somewhat redundant and may conflict perhaps (as mentioned if you tell a DVD player there is no sub most of them discard the LFE). Thus I suggest you set all speakers as large and subwoofer as present at the NAD, then let the Yamaha "worry" about the rest.

 

[Nimby]

Sounds like the best way to do it.

Hm, since you apply settings in the Yamaha and NAD they are somewhat redundant and may conflict perhaps (as mentioned if you tell a DVD player there is no sub most of them discard the LFE). Thus I suggest you set all speakers as large and subwoofer as present at the NAD, then let the Yamaha "worry" about the rest.

Thanks Reiner.

Your post finally has me thinking furiously about how my system is actually set up. Not before time!

I shall have to ask NAD what happens to the LFE since the manual says nothing unless I've missed it (again).

I have just realised that my Front Mains signal cables are still connected only to the analogue stereo sockets! Which means I wouldn't get any bass redirection to the mains anyway!

I watched films in stereo + sub for a couple of years and forgot to connect the Front Mains signal cables to the 6 channel analogue surround sockets as well! I also use the NAD as a CDP. Which is my excuse for this slight oversight.

I dutifully connected the 6 Channel signal cables from the DVDP to the Yamaha E800 when it arrived. Since then the Yamaha has probably been doing absolutely nothing except amplify the rear speaker channels.

Time to play with the toys again.