Help with Rel!

Big ears.

Is it not possible to take the signal from the hicap?

Assuming the rel has an amp in it of course.

Gary

Richard Lord recommends that you drive his subs from the power amp (as you have correctly done) to feed the sub the same character of bass, as your main speakers.

Naim recommend that subs are driven off a spare pre-amp output.

Difficult to know who's right.

I've used REL subs driven from power amps, and have not been aware of the effect you describe. The sub should not be sapping power to your main speakers.

I would guess that you are hearing the effect of the sub not integrating with your main speakers and screwing up the timing.

The golden rule is to keep it subtle. Set the frequency cut off, as low as possible and have just enough gain to hear it working.

Set up correctly; you should only be aware of subtle sub-bass and an opening up of spatial information in the mid and high frequencies. The bass of your main speakers should be unaffected.

It does take a while to get it right.

Good luck.

If you're using ported speakers, then the phase switch should probably be switched.

cheers, Martin

E-mail:- MartinPayne at Dial.Pipex.com

Gary

I had roughly the same problem as you trying to connect my REL QUAKE across the speaker outlets as recommended by REL.
My 150 did not like it! I
n fact I got an intermittent crackling noise on one of my speakers.
NAIM recommended using a spare output on my HiCap into the REL's line level input as reported here which I did.
That works fine. It is also true you have to tune the bass output very carefully so it blends in to the background but it is worth persevering and REL subs have pretty comprehensive tuning controls so you should be able to get a good result.

GEOFFP

Hi Gary

Puzzling

A couple of things to try.

1. Ensure that the REL interconnect is not coiled up. Any excess should always be removed, otherwise excessive reactance is put on the Naim amp. Same applies, of course, to any power amp, not just Naim.

2. I believe the 135's are normal stereo monoblocks. Meaning they are not differential (bridged) outputs. I could be wrong about this, but whatever, try putting the black wire of the REL high level interconnect to any one of the input signal grounds - you will need to use a spare and unused input and plug. Or, try connecting to the Naim chassis ground.

Most important: switch off everything before doing anything at all!

I have a suspicion that Naim do not use the usual Zobel output reatance circuit on their amps. This means there may be more chance of incipient instability with that extra interconnect. Perhaps Naim can elaborate about this. We have Naim equipment (and I have owned it personally) and I have never experienced any problems whatsoever.

Just for others benefit, all REL subs are active. The input impedance is over 10K. A thousand times higher than your speaker load. However, that is the resistive load, the interconnect reactance is of far greater significance. Whether it is sufficient to tip over the 135's, I have no idea. We have many customers with Naim amps and so far as I know, no problems.

As some of you may know, I am a bit of a Flat Earther. I strongly believe in the downhill principle, the higher up the chain (meaning the nearer the source), the greater the importance and the more delicate the signal.

Any damage done upstream can never be put right by anything else further down the signal chain.

That said, the REL can add an extra dimension to sound staging provided reasonable care is taken over setting it up. Please see our Web site for more info regarding this.

If none of this helps, please give Eric Morris a call and ask him what he suggests.

Hope this helps.

Richard Lord

quote:

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Just for others benefit, all REL subs are active. The input impedance is over 10K. A thousand times higher than your speaker load. However, that is the resistive load, the interconnect reactance is of far greater significance. Whether it is sufficient to tip over the 135's, I have no idea. We have many customers with Naim amps and so far as I know, no problems

---

Richard,

Hi - welcome!

The most successfull Naim/REL combination I have heard (I.E. completely without compromise) took the connections from the speaker end of the A5 cable, rather than the amp end. The cable therefore isolates the capacitative load of the interconnects.

It's also worth pointing out that he used low-capacitance speaker cable to connect the the sub, instead of the supplied lead.

Naim amps *really* hate a capacitative load, for exactly the reasons that Richard suggest.

cheers, Martin

P.S. for anyone who hasn't noticed, this is Mr "Richard E. Lord".

E-mail:- MartinPayne at Dial.Pipex.com

Richard

Thank for your helpfull e-mail.

Also I note what Martin pointed out

quote:

---

The most successfull Naim/REL combination I have heard (I.E. completely without compromise) took the connections from the speaker end of the A5 cable, rather than the amp end. The cable therefore isolates the capacitative load of the interconnects.

It's also worth pointing out that he used low-capacitance speaker cable to connect the the sub, instead of the supplied lead.

Naim amps *really* hate a capacitative load, for exactly the reasons that Richard suggest.

---

In my earlier comment on this thread. I mentioned that I had adopted Naim's recommendation of using my HiCap to provide a line level signal.
This is working well at least with my REL quake. In your manual (which is excellent in it's explanation of how to set up the bass output from the Quake, by the way) reference is made to the advantage of being more able to control the input signal level at the Neutrik high level input.

BUT I actually found your gain control also works well with the line level and that the setup instructions for the Neutrik can also be made to work with the line level input.

Using the output on the HiCap means you are taking an exact replica of the signal you are feeding from the pre-amp to the power amp so of course the "volume" control is built into the both signals which means that the output to the sub "tracks" the output to the power amp.

The connection for the sub is a little tricky because you need a special connecting lead (which NAIM dealers can get for you if necessary) which is basically SNAIC connector with NO power leads, only audio in it. You also then need to join the two signals (Left & right stereo) together to feed the REL with the combined channels so it can deliver the "dialled in" bass frequencies range regardless of which channel they are in.

That works for me. I would welcome any comment or opinion on this approach

GEOFFP

e-mail geoff.phillipps@asml.com

Geoff,

the chap I mentioned above tried connection at the socket of the Super powering his 52 and found the extra capacitance & RF pickup of the long lead really brought the performance of his 52 down too much (it is in parallel with the connection to SNAXO or power amp, and it says in the manuals to use only the cables supplied). Note that the load seen by the output stage of the 52 will be affected by this cable.

BTW, this was the best active SBL system I have ever heard (CDS2/52/2xSuper/SNAXO/2x250) - just sweet music whatever you played - as long as the REL was switched on. It was set *very" quiet, in fact I never actually heard it, even on stuff like Leftfield.

I remember when he switched the REL off for a few seconds, though - the sound became very coarse, by comparison.

On this basis I would *strongly* suggest you to follow the setup advice above - tap from the speaker end of NACA5, and maybe use a very low-capacitance cable to make the connection, too.

cheers, Martin

E-mail:- MartinPayne at Dial.Pipex.com

Hi Martin (and Simon, et al)

I am very interested in the suggestion to put the REL at the end of the line, so to speak. As you say, by connecting at the speaker terminals rather than the amp. That sounds (bad pun intended) a very good idea. It places the extra interconnect to the REL in series rather than in parallel with the Naim cable.

I am going to investigate alternative interconnects, perhaps with the cooperation of Naim, to ensure minimum capacitive load.

Watch this space.

I particullarly agree that the REL must not be set too high or intrusively or it will mess up the whole system and just reinforce the prejudices that surround subs. It is imperative that care be taken over setting up. I strongly urge anyone with a REL to read our latest setup instructions on our website - www.rel.net

Richard Lord

Richard,

just to confirm your point above, Naim power amps do not have a Zobel network. This function is provided by the A5 speaker cable, and by connecting at the speaker end of the cable the amp is fully protected.

cheers, Martin

E-mail:- MartinPayne at Dial.Pipex.com

Richard & Martin

Very good information. I will try connecting the high level output across the speaker terminals for comparison.

I agree entirely with the comments about carefull setup for low level delivery from the REL.

I find I get a similar effect to your friend with the 52. Basically you cannot hear the extra bass as such, you only know it is being generated by gently feeling the movement of the speaker cone on the REL, but it provides a "lift" to the whole sound of the system which is not limited to the bass frequency's but seems to occur in the mid range aswell.

A similar interesting effect is reported and claimed for the addition of a supertweeters to each speaker aswell though I have not tried it or heard it in action.

By the way I have 5 series gear (112/150) which I understand is more tolerant to capacitive loads than the older generation systems. This has been confirmed by NAIM, though that is not to say that it is completely immune, and I am not representing it as official information.

regards

GEOFFP

Martin Payne wrote

quote:

---

The most successfull Naim/REL combination I have heard (I.E. completely without compromise) took the connections from the speaker end of the A5 cable, rather than the amp end. The cable therefore isolates the capacitative load of the interconnects.

It's also worth pointing out that he used low-capacitance speaker cable to connect the the sub, instead of the supplied lead.

Naim amps *really* hate a capacitative load, for exactly the reasons that Richard suggest.

---

Martin

I have now done as suggested. This works!

I did re-wire with low capacitance cable as advised (NACA5 is a bit too thick to allow connection into the Neutrik plug soo I had to use some other cable I have), and spent about 1/2 an hour crawling back and forth into the room corner to tweak the settings on the REL.

The advantage of using the high level input on the REL is it offers much more setup flexibilty.As previously mentioned though you have to be patient to find the blend of frequency roll off and gain that just "lifts" the music without making the sub's presence obvious.

Incidentally I noticed when I was using a connection from the HiCap that as I drove the system to higher volume levels I could detect "clipping". With the speaker connection the "clipping" does not start until much higher on the volume control (way above normal listening level !)

I look forward to what comes out of Richard's "watch this space" comment.

regards

GEOFFP