Nait 5i and Unitiqute as streamer - hiss on A/V in under unity gain

Posted by: Paul O'Connell on 31 January 2018

Hi,

I've just set up one of my systems like this.

Unitiqute 1 (but with upgraded 192k board) preamp out into a 5i (speakers set to off), with the A/V input on the 5i set to unity gain. 

The system is:

Nait 5i

CD51-2 (connected via Din)

Qute (connected via RCA)

Energy Connoisseur C3s connected with 5m of NACA5. 

All items into one powerboard and all running the original factory power cables. 

What I'm trying to do here is retain the volume control via the Qute on the app, and get a bit more amplification. 

It's also a future proofing thing - this gives me option value in the future to run the Qute separately and get another streamer for the 5i so I can continue to have three Naim setups in the house. 

And . . . . here's the problem - when I do this there's a lot of hiss out of the speakers.  Noticeable, god that's annoying, aghggh, hiss.  Not transformer hum, and I'm reasonably certain it's not a ground loop.  Shifting the ground on the Qute from chassis to floating makes no difference.  Changing changing RCA cables or shifting RCA cables out of the path of power cables and speaker cables makes no difference. Changing the max speaker volume of the Qute makes no difference.  Moving the units away from each other makes no difference.  

If I run the Qute into the tape input, set the volume to 90, and control volume via the 5i volume control then it's fine.  But now I've lost volume control via the app, and if I use the remote it adjusts both the 5i and the Qute at the same time. 

This seems to be a known issue as I've seen several variants of this complaint on the forum, but I haven't seen any known solutions.  My local Naim guy thought it was that I was doing something that it wasn't designed to do and the sound is an artefact of the amplifier on the 5i being wide open when set to Unity gain.  

Any thoughts?  Would be really cool if I could get this set up to take advantage of that unity gain function.  

Cheers,

Paul. 

 

 

Posted on: 31 January 2018 by Gavin B

In the ‘tape input’ scenario doesn’t the app still control the Qute volume and hence what gets output to the amp?

Posted on: 31 January 2018 by Gavin B

The issue of the two remotes is easy to solve - it’s easy to change the codes for the Qute

Posted on: 31 January 2018 by Paul O'Connell

@Gavin B - yes, but then I have to have the 5i set quite loud to have any effective volume control.  And when I switch that over to the CD player and forget to adjust volume, boom it's loud! 

Posted on: 31 January 2018 by Adam Zielinski

Paul - why exacrly are you doing this?

Uniti’s amp is more than capable....

Posted on: 31 January 2018 by Adam Zielinski

Uniti gain is designed specifically for home-theater integration. 

Nait 5i does not have a dedicated power-amp socket, that bypasses the power-amp in a true sense. Whilst UnitiQute does have an extrnal power-amp capability, it should not really be connected via an AV input.

Anyway... have you set the Uniti’s speaker setting to OFF via the system’s menu?

Posted on: 31 January 2018 by Paul O'Connell

It's an option value thing mainly. We've got an atom, a qute, and a 5i. 

The house we're in at the moment has space for two, but not three systems.

I'd rather have it running than in storage and I like the 5I's sound. 

 I don't want to spend a bomb on another streamer. And theoretically this should work- if it takes a receiver out it should take a qute preamp out.

 

 

Posted on: 31 January 2018 by Adam Zielinski

And my last question?

Posted on: 31 January 2018 by Paul O'Connell

Yep, speakers off. 

Posted on: 31 January 2018 by ChrisSU

I would sell the 5i and get a NAP 100 or 200 if you need more power, then it will all work as intended.

Posted on: 31 January 2018 by Paul O'Connell

But then I lose the option value. That means when I separate it I need a preamp and a streamer to run the nap. 

What I'm trying to establish is why this function, which should do this, doesn't seem to work.

Would a lower powered output not have this problem (ie a chromecast audio?). 

Posted on: 01 February 2018 by Richard Dane

Paul, it may be because the NAIT 5i is a bit different in design to the other amps - it has a passive pre with an additional gain stage built into the power amp to compensate.  I would guess that in Unity gain mode that extra gain stage can't be bypassed hence maybe why it's a bit noisier?  I'm sure Naim could give you a valid explanation here.

Posted on: 01 February 2018 by Gavin B

Sounds like the solution is to run it into a 'normal' input and just use the Qute as a source (and not be able to control the volume in the app).

Posted on: 01 February 2018 by Paul O'Connell

Thanks Richard.  Yeah, it seems to be something along those lines. 

My local dealer (who is also the importer for NZ and Australia) said "it could be something more to do with the output voltage of the Qute into the wide open unity gain circuit on the nait."  

If I had the cash I'd run it into a NAP 100, as it stands I'll just run with what I've got.  (I spent the money today on some Focal Speakers . . . )