Dual mono with REL Subwoofer

[audio_engr]

Just added a pair of REL G1-Mark IIs to my system a fews days back. They sit on the outside of my B&W 802 D3s and just about 1 feet back, toed-in slightly more than the main speakers so that they fire into the diagonal rear wall corner. 

Soon after they were setup & dialled-in, a day or two later, 3 long-standing & experienced audiophile buddies of mine dropped for a listen and all these 3 fellas had advised me against adding subs. Each one of them (in-turns) sat in the central stressless Listening Seat w/ ottoman and heard a couple of their fav tracks from Tidal & Qobus. Their collective verdict was "what are all your B&Ws, Devialets, expensive highend Audioquest cables and all the rest of the gear doing with such a humongous amount of investment on them vs. the pair of RELs thats completely a show-stealer ?" Honestly - I silently am in total agreement with them. I was telling my wife that "no speaker upgrade, amp change, cable/s change, source change can bring forth the upward level of performance shift these pair of RELs have done" and she too is in complete agreement. G1-Mk2 pair is quite a bit of money but I don't have a single regret on this purchase; infact I'm pulling my hairs why didn't I do this earlier ... 

credits - @marcor  You were a great help for the High-Level connections of the RELs with Devialet. 
The 3 wires of the REL High-Level cable on the amp side were:
Red = right ch positive, Yellow = left ch positive, Black = Ground post of Devialet under Line inputs thats typically meant for Phono. 

[Laura]

@audio_engr Welcome to the Dual G1 Mk2 club! I'm pleased that adding them to your system had the same amazing effect that it did on mine. I've had mine for 9 months now and they still have the ability to surprise me with how much they have improved my system. The slight problem now though is that we can never go back to just speakers on their own 

[devianet]

Just to mention that I've also successfully connected my REL, using the 3-wire method, to a dual mono setup. Works just as well as with a single stereo unit.

In my case I used one of the 0v (i.e. black) speaker terminals for the REL 0v black wire rather than the ground post.

However, shortly afterward I experimented once again with using the Expert sub-out at line level. Using this allows me to set a 4th order rolloff and a much superior result versus relying on the REL crossover set to the lowest frequency. This is because filtration of 40hz+ content is much better and it doesn't interfere with the very quick and clean bass from my floorstanders in this region. So effectively the 16-25hz region can be brought up in volume to match the higher frequencies, with really stunning results (even though it was pretty good previously!)

So after 25 years of using the 3-wire connection on various RELs, I'm finally abandoning it.

[PeppaPig]

Just to mention that I've also successfully connected my REL, using the 3-wire method, to a dual mono setup. Works just as well as with a single stereo unit.

In my case I used one of the 0v (i.e. black) speaker terminals for the REL 0v black wire rather than the ground post.

However, shortly afterward I experimented once again with using the Expert sub-out at line level. Using this allows me to set a 4th order rolloff and a much superior result versus relying on the REL crossover set to the lowest frequency. This is because filtration of 40hz+ content is much better and it doesn't interfere with the very quick and clean bass from my floorstanders in this region. So effectively the 16-25hz region can be brought up in volume to match the higher frequencies, with really stunning results (even though it was pretty good previously!)

So after 25 years of using the 3-wire connection on various RELs, I'm finally abandoning it.

I am also using dual REL subs and dual mono Expert.

Can you please tell me how you configure it to use sub out? Any screenshot of your expert config page can be shared.

In this setup you connect the 3 REL wires into the sub output post?

Thanks

[devianet]

I think there are 4 sockets on the pair that can do line-out. This can be left, right, or a mono mix of both. They are RCA sockets 5 and 6 reading left to right as shown on the configurator. 

But socket 6 is used for the digital link between the units, leaving only 2 sockets remaining. On my master I'm using socket 5 for a digital in, so my obvious choice is socket 5 on the companion, as shown in the picture.

The 3 wire connection is not used at all and the sub is set to "LFE" mode which disengages its crossover.

For a pair of subs you could use a splitter adaptor, but each sub would see a mono mix.

For stereo, if the socket 5 of both units is available, just set the mix of each socket to left and right correspondingly. If I really needed to free up my master socket 5, I could move that source to the AES input on the companion, which is currently unused.

[PeppaPig]

I think there are 4 sockets on the pair that can do line-out. This can be left, right, or a mono mix of both. They are RCA sockets 5 and 6 reading left to right as shown on the configurator. 

But socket 6 is used for the digital link between the units, leaving only 2 sockets remaining. On my master I'm using socket 5 for a digital in, so my obvious choice is socket 5 on the companion, as shown in the picture.

The 3 wire connection is not used at all and the sub is set to "LFE" mode which disengages its crossover.

For a pair of subs you could use a splitter adaptor, but each sub would see a mono mix.

For stereo, if the socket 5 of both units is available, just set the mix of each socket to left and right correspondingly. If I really needed to free up my master socket 5, I could move that source to the AES input on the companion, which is currently unused.

Thanks for your information.

So for my 1000 Pro and I have two REL subs.

I can set each mono block to use one post for sub and set it to Mono mode?

[devianet]

Yes, you could. Or, as you want the subs to play the mono sum, and if you want to save a socket on the back on the amps, you could just use one socket, with a phono y-adaptor branching off to both subs. You don't actually need two sockets in this scenario.

The scenario where you do actually need two sockets is the stereo-sub scenario, where each sub takes the bass of its corresponding main-speaker only and not the mono mix. In that case the configurator gives you the option to set each socket to be left or right channel, and not the mono mix of both that you'd use above.

[devianet]

A couple of further things I should have mentioned earlier -

Long single-ended line connections to subwoofers are much more susceptible to hum than speaker-level. I unfortunately have an unavoidable run of 25 metres (!) Well-shielded cable is key with longer runs like this.

It's worth cranking up the maximum output voltage on the Expert (mine is set to 4v, as high as it will go) and - correspondingly - reducing the low level input volume on the subs. That way you're as high as possible above the noise floor of the cables.

I'm very happy with mine, even with the 25 metre run.

[PeppaPig]

A couple of further things I should have mentioned earlier -

Long single-ended line connections to subwoofers are much more susceptible to hum than speaker-level. I unfortunately have an unavoidable run of 25 metres (!) Well-shielded cable is key with longer runs like this.

It's worth cranking up the maximum output voltage on the Expert (mine is set to 4v, as high as it will go) and - correspondingly - reducing the low level input volume on the subs. That way you're as high as possible above the noise floor of the cables.

I'm very happy with mine, even with the 25 metre run.

Thanks Devianet for the detailed information.

[PeppaPig]

I think there are 4 sockets on the pair that can do line-out. This can be left, right, or a mono mix of both. They are RCA sockets 5 and 6 reading left to right as shown on the configurator. 

But socket 6 is used for the digital link between the units, leaving only 2 sockets remaining. On my master I'm using socket 5 for a digital in, so my obvious choice is socket 5 on the companion, as shown in the picture.

The 3 wire connection is not used at all and the sub is set to "LFE" mode which disengages its crossover.

For a pair of subs you could use a splitter adaptor, but each sub would see a mono mix.

For stereo, if the socket 5 of both units is available, just set the mix of each socket to left and right correspondingly. If I really needed to free up my master socket 5, I could move that source to the AES input on the companion, which is currently unused.

So my master amp I set one post to Mix Mono, and companion I also set one post to Mix Mono, and set the cutoff at 40Hz. Then I connect each subwoofer to each master and companion using the LEF connection on the subwoofer?

Then what about the crossover on the subwoofer? Turn it to max? What about volume?