Direct 2.1 possible ?

Posted by: Roy Donaldson on 14 May 2005

Hi there,

Just before heading out tonight, I've been playing a lot of more dance orientated CDs. I normally have my AV2 setup to run in Direct mode off the CD input. However, tonight I've set it up to process it in DPLII Music, to gain access to routing the LFE to the subwoofer. This also unfortunately brings in my center and rears, which I don't really want running on a CD. but the low bass going out to my Rel is quite nice Smile

I don't think there is, but was wondering if there is a way to set the AV2 up to run in a Direct mode, but with the low frequency filter routing below 80Hz out to the sub ? ie. a kind of Direct 2.1 mode ?

Roy.
Posted on: 14 May 2005 by Mr Underhill
Roy,

I use a REL with a high & low input.

The low is connected direct from my 250 to the REL, therefor I have the sub in circuit even when I'm not using my AV2.

If you have a similar facility on your sub the low freq will go to it even in direct mode.

M
Posted on: 17 May 2005 by moz
Roy

I think the normal 'stereo' mode should solve this for you, simply change mode when listening to a CD.

Moz
Posted on: 17 May 2005 by Roy Donaldson
Yeah, my Rel has the high and low level inputs. I currently only have the low level connected up at present.

I was hoping that I could just use the AV2 to send a LFE to it perhaps.

I have tried Stereo and that does not send anything out the sub output unfortunately.

Roy.
Posted on: 18 May 2005 by Frank Abela
Roy

You need to connect both low and high inputs. Connect the high inputs to the speaker terminals and into the REL with the speakon connector (most RELs come with this cable for free). You can either connect across the front channel amp outlets or, for a better result, you can wire up to the speaker terminals themselves. Then you need to setup the REL to integrate for stereo (it has a separate set of controls for the hiogh level input).

The REL will automatically detect when it gets a low level input and use that when present (surround applications). When it's not present the REL automatically takes the high level input from the speakers. All RELs have this facility AFAIK.

It is better to wire to the speaker terminals rather than a Naim power amp terminals because if you do this, the Naim still sees a single set of speaker cables. If you connect at the amp end, it 'sees' a biwire load, which isn't as good.
Posted on: 19 May 2005 by Frank Abela
Why would you solder them to your Naim plugs? Would it not be easier to simply piggy back into the speaker terminals or amp sockets? The cable that REL supplies is a very thin affair so it should fit fine.

Of course, to do it right, you'd have extra sets of NACA5...

This solution provides the best sonic result generally speaking, integration being easier to manage and timing rarely being affected. All things being equal, I find that using low level LFE output generally affects timing adversely by comparison to using the high level solution.
Posted on: 19 May 2005 by Geoff P
quote:
Why would you solder them to your Naim plugs? Would it not be easier to simply piggy back into the speaker terminals or amp sockets? The cable that REL supplies is a very thin affair so it should fit fine.

I know it sounds crude but the supplied REL wire is thin enough that if you bare the ends and fan out the multistranded wire revealed you can actually fold it onto the NACA5 speaker plugs and carefully push the plugs into the speaker terminals (or amp sockets if you prefer) trapping the REL wires in contact inside the sockets.

Regards
GEOFF
Posted on: 19 May 2005 by i am simon 2
HT

Perhaps you should search the forum for posts by Richard E Lord ( no his initials are not a coincidence) He has cleared up many queries on this subject, and I have always found his advice most helpful. In fact, I am suprised that he has not yet posted on this thread, (unless it is no longer PC for him to post since Naim built thier own sub base system)
Posted on: 28 May 2005 by General Skanky
I have an AV2 on loan this weekend with a view to buy.

The Stereo + sub is something I wanted to know too.

It can be done.

Download the latest manual from the website and it is under section 10.8 Accessory Functions. It's called Bass Mix.

You can add bass to the stereo pair by pressing Menu and 1 to enable/disable this feature. It only works if your main speakers are set to large.
Posted on: 28 May 2005 by General Skanky
Unless you already knew that and wanted more specific bass management. Roll Eyes
Posted on: 29 May 2005 by General Skanky
quote:
Hence only works for Dolby x.1 encoded software


I thought that the bass mix added bass to audio 'without' any form of bass in stereo?
Posted on: 29 May 2005 by General Skanky
The bass management is the only unclear area to me with the AV2.

For instance, when the front speakers are set to large, at what xover frequency does bass get routed to the sub? Or is it only when there is a x.1 soundtrack available that bass goes to the sub? If so, is it purely dependant on the source information?
Posted on: 29 May 2005 by cchua1
I don't know the answer to Gen. Skanky's question (what x-over frequency gets routed to sub when speakers set to large vs small). Shd be interesting to hear from Naim. I was told that it's better to set all speakers to large unless you have small or tiny speakers.
To get 2.1 sound with the REL, it looks inevitable that we have to use both the low & high inputs to the REL. Would have thot that the most practical way to do this was through the amplifier outputs but Frank's response on this thread has made me re-think. My comment though on the sub's contribution in direct and pro logic is going to sound quite different. I've used my REL Storm in direct mode for music-only and I barely notice it unless the music contains low frequency sounds. If I increase the volume higher, the low frequency begins to intrude and I don't get such a coherent sound. In pro logic/5.1 mode, the sub is more noticeable but even then, I still think that if U notice the sub, U've probably set the volume levels too high. There isn't that much musical content below 40 Hz. Of course, that's not the case for movies.
Posted on: 29 May 2005 by General Skanky
The AV2 I have on loan has the latest software version. Checked it.

If I select small speakers I put the xover to 60Hz as that's a good point with ATC active 10s. However, I believe (but naturally it may be wrong), that by using any form of bass management will introduce a level of distortion to the sub output, an old HiFi Choice article explained this.

The conclusion was to always set speakers to large. However, when you do this on the AV2, the overall bass reponse diminishes and I don't know why.

When you select large on the AV2, you appear to lose the bass mangement, so hence my confusion as to the xover etc.
Posted on: 29 May 2005 by General Skanky
I now see what the original post was about too.

I was confusing stereo mode with the direct option.
Posted on: 29 May 2005 by Roy Donaldson
I have all my speakers setup to be Small, this is usually what THX suggests as a good setting all round.

When I set the AV2 to Stereo, it doesn't seem to route a LFE below the crossover frequency to the sub still. I haven't had much time to play with it recently, but hopefully will be able to try it more tomorrow.

The new manual definately says that if you have Stereo selected and turn BM On, that it will route bass to the sub. My main speakers are set to Small, so I'm not too sure.

Will see how I get on tomorrow.

Roy.
Posted on: 29 May 2005 by niceguy235uk
I am running An Arcam AVR300 surround reciever which does have a stereo + sub setting. Even in Direct mode you still have the same signal information routed through the amp but just to the fronts and sub. You can of course specify if you want the sub to run in direct mode. I also run a REL sub and find that the Hi level input of the sub is much, much better than using the LFE channel in stereo so much so that i turn off the LFE input of the sub when listening to music (which REL do suggest in the maunal i think).
I know it isnt an AV2 but i just thought you might like to know.

regards
Posted on: 29 May 2005 by niceguy235uk
just read in article regarding the av2 that the sub output is basically turned off intentionally is stereo mode. The reason being obvious i suppose.
Posted on: 29 May 2005 by General Skanky
Headache. Smile
Posted on: 29 May 2005 by Roy Donaldson
Yes, big Headache.

If you read the DVD5/AV2 manual, page 26 shows that in stereo procesing mode, the sub-woofer is enabled (Note 1) and the note says that the sub-woofer will only operate if Bass Mix is selected.

If you then read 19.7.2 (page 27) this says:

"The Bass Mix option routes main left and right loudspeaker bass information to the sub-woofer. Note: Bass Mix is useful for encode formats that carry no specific sub-woofer information.".

So, seems like what I want. Now I just need to check how this will work with my speakers set to Small and a xover frequency of 80Hz.

Roy. (who's Ron ?)
Posted on: 30 May 2005 by Roy Donaldson
Well, tried all combinations this morning.

Small/Large in Stereo mode, using BM doesn't route anything to the sub at all.

Oh well.
Posted on: 30 May 2005 by cchua1
HT-Naimee, you are absolutely right about the problems of wiring both the high and low level inputs of the sub. Even if the REL automatically selects the low input (if it detects both signals) and actually allows output adjustment of hi and low inputs level inputs to be done separately. At the end-of-the day, it's too much hassle and the results weren't satisfactory. Eventually, my sub is dedicated to 5.1 playback for movies. I can live w/o a sub for music playback - there isn't much low frequency information below 40 hz in most recorded music. However, a sub is indispensable for creating the visceral impact and experience (you know what I mean if U've experienced it) that makes HT so thrilling.
Posted on: 30 May 2005 by Roy Donaldson
I've been using the AV2 with only the main 2 speakers being driven for CD playback for ages now and find it great.

However, it was while I was playing some dance tracks before going out one evening that I thought that the sub was just sitting there going to waste, when it could have been helping out.

I selected DPLII Music as the decode and it routed a lot of bass to the sub, that obviously my mains had just not been able to deal with.

That's really why I thought it would be nice to be able to run it in Stereo, 2.1 mode more than anything. Bit disappointed that it doesn't do it to be honest.

Roy.
Posted on: 30 May 2005 by General Skanky
Same here.

My Arcam AVR200 can do it, my Arcam DV27A can do it. It is a useful feature.

I believe a sub is as essential in hifi as much as it is in AV, regardless of perceived bass content.

I think that better bass management, if possible, could be implemented in future upgrades.

Otherwise the AV2 is superb.
Posted on: 30 May 2005 by niceguy235uk
HT...

On the Arcam you can set the stereo output to include a sub even if you have large speakers. On the sub settings menu you can set the x over to what you want from 40hz up to 120hz.

Sorry just seen the Generals post..
Smile
Posted on: 31 May 2005 by Adam Meredith
Please find attached some clarification.

- LFE only exists for 5.1 material (low frequency effects), it is the 'point 1' channel and is discrete sub information band limited to 120Hz (Sorry, being pedantic!)

- Sub information for stereo sources when speakers are set to small is a result of bass management. (Bass management is the process of redistributing the bass to suit the speaker sizes)

- Sub output can be generated whatever the speaker configuration by enabling BASS MIX (All modes except DIRECT)

- In DIRECT mode all the digital processing circuits are switched off.
Left and right analogue audio is routed from the selected input socket, through the volume control then to the left right output. The sub output is inactive in this mode.

- In STEREO mode sub information is only present if speakers are set to small or Bass Mix is enabled

- In 5.1 modes sub information is present for the LFE channel (the 'point 1') and also if speakers are set to small or Bass Mix is enabled

Additionally - If you do not want to, or cannot, use a high level feed from the rear of the speakers you can obtain a 2 channel, volume dependent, output from the AV2 on either "front out" OR "analogue in 3" (main out). This full range signal can be fed to your sub woofer, using the sub software to set the roll-off frequency.