Naim NAIT 5i - distortion when trying to bi-amp

The simplest solution is not to biamp, which tends not to work well with Naim. The Nait's tape out is a line level rather than preamp level output so not designed for biamping.

Thanks for your reply.  I found it strange, as the NAIT would instantly become louder when I turned on the Denon that I was trying to bi-amp.  I don't want to cause my new (and first) Naim any damage, so I've decided to leave the signal clean and not use the Tape Out.  I think I'll have to wrangle my way around it by buying a CD player with co-axial and an optical output.  That way, the NAIT can recieve the analogue signal and my Denon can receive the optical.  Any other input devices that I require in 5-channel mode (TV/DVD) - I can send the front left and right to the NAIT via the Denon's pre-outs.

Do you think this whole Tape Out distortion problem would be solved by sending the NAIT for a service?

Cheers,

Karl.

Karl,

The Nait instructions describe how to do what I think you are going for.  Look for the term "Unity Gain" or "AV Bypass".  Line Out from the Denon to AV In on the Nait is probably what you want to use, if you are adding the Nait to a 5.1 system.  Nait would replace the Denon amp section for just the Left and Right channels.

Sources like CD should not need to be wired into more than one amp at a time.

Nick

The HDD out isn't suitable to use for bi-amping as it's a line level output not a pre-amp output (i.e. it comes before the volume control not after it).

The Nait 5i uses a 'passive preamp' i.e. there isn't a buffer amplifier in there.  The result is that any interconnect cables connect to the HDD out are effectively connected to the output of the CD player in series with the cables connecting the CD to the amplifier.  This is putting too much load on the CD player.  Using lower capacitance cable may fix the problem, but in reality, unless you have odd or very long cables connected to the HDD output, it seems that the CD players output appears to be excessively sensitive to load.

Do not bi-amp. Just use good quality jumpers, to match your speaker cables. Do pay attention to the minimum recommended length of the speaker cable and it's capacitance and inductance  to make youe Nait happy.

Even my relatively abused ears could tell the NAIT wasn't enjoying itself - so I've found away around it.  There is now a clean signal via Black Rhodium coaxial interconnects from each of my devices to the NAIT, powering the Linn AV-5140 speakers (again, via Black Rhodium speaker cable).  The Arcam DrDock luckily also has a coaxial digital out that I've now hooked up and assigned to the Denon, to enjoy both the main NAIT sound and the Denon's audio output (to Linn Trikan and Mordaut Short 902i speakers).  Likewise, the CD player has a digital optical out as well as coaxials, so the optical is assigned to the Denon.  A volume contol for both sets of speakers is ideal for my set up.  The TV/DVD are connected to the Denon and the main front left and right signals are now sent to the NAIT via the Denon's pre-outs using the Unity Gain.

It's never sounded better, so thank you for all your help, my good Sirs!

I'm really surprised and grateful for all of your input.  (slight pun intended)

Cheers and have a great weekend.

Karl.

If you run HDD Out from the Nait 5i to the Denon into CD or AUX, the CD player connected to the Nait would not need to be directly wired to the Denon.  Naim CD players CAN output to analog and digital at the same time, but doing so is said to degrade sound quality.

It is common to get ground-loop hum when connecting two systems this way.  If that happens, insert isolators on the lines between the two amps.   

Nick

Nick, using the HDD out to drive two devices at the same time via a Nait 5i isn't advisable if you can avoid it, as there's no buffering pre amplifier in the Nait 5i, so the analogue out of the CD then has to drive both cables, the Nait's volume control and the input of the other amp.  This seems to be causing a problem to the OP's CD player, specifically the interconnect cable's he's using seem to presenting an inappropriate load to the CD player.

Thanks, Huge.  I have been tripped up by this "buffering" detail in these discussions before, and do not want to give bad or misleading advice.

I understand buffered Line Out is provided on NAC 282 and up, is that correct? 

I can testify that I have used the AV In and Out of both my old 112 (not 112x) and new 552 into Denon AV amps to equally good effect.

Was the 112 buffered?  What is the effect of buffering?

Regards,

Nick

I don't know about the earlier pre-amps.

There are also three configuration of buffering (or it's abscence) under consideration

First.  No buffering at all, i.e. a passive 'pre-amp'
The inputs are connected directly to the 'hot' terminal of the volume control via the source selector switch.
The HDD out (or tape out) is connected to the 'hot' terminal of the volume control.
Thus anything connected to the HDD out (or tape out) is directly connected to the source component
   - there's no buffering at all.
Nait 5i seies

Second.  No buffering of the output signal after an active pre-amp
The inputs are connected to the input of the pre-amp via the source selector switch.
The output of the pre-amp is connected to the 'hot' terminal of the volume control
The HDD out (or tape out) is connected to the 'hot' terminal of the volume control.
Thus anything connected to the HDD out (or tape out) is connected to the output of the pre-amp
   - so the pre-amp buffers the source component, but not the volume control.
Nait XS, & SN

Third.  Fully buffered.
The inputs are connected to the input of the pre-amp via the source selector switch.
The output of the pre-amp is connected to the 'hot' terminal of the volume control
The HDD out (or tape out) is connected to the 'hot' terminal of the volume control via a buffer amp
Thus anything connected to the HDD out (or tape out) is connected to the output of the buffer amp,
   - so the buffer amp buffers the pre-amp output and the volume control.
NAC 282 & up

Other components...  I've no idea!

Huge,

Many thanks.  With answers to my questions below, I will nominate your description for the FAQ list.

Are all of these configurations suitable for use with tape recorders?  If not, what are the practical considerations?  Are some of them variable-level, due to involvement with the Volume pot?  Variable levels are not ideal for either recording or distribution, I would agree.

I can imagine that not being isolated from the pot might impart noise, maybe when the knob is turned, even if the output level were fixed. That would be bad during recording, but only a momentary annoyance in a whole-house distribution scenario.  

Even yet, I cannot infer the precise differences these distinctions make.  Still guessing.

Looking forward to finally getting this!  

Nick

NickSeattle posted:

Huge,

Many thanks.  With answers to my questions below, I will nominate your description for the FAQ list.

Are all of these configurations suitable for use with tape recorders?  If not, what are the practical considerations?  Are some of them variable-level, due to involvement with the Volume pot?

... 

 

All can be used with tape recorders (or HDD recorders) and the output is always fixed at output level (it's taken from the 'hot' end of the volume control not the wiper of the pot), however...

Config 1 (passive preamp)
   the amp to recorder cables and the input impedance of the recorder load the output of the source component and can degrade sound quality.

Config 1 (output taken directly from the pre-amp output)
   the amp to recorder cables and the input impedance of the recorder load the output of the pre-amp and can degrade sound quality (but less likely than with Config 1).

Config 3 (full buffering)
   Little or no chance of SQ degradation in the main signal path even if an recorder with an incompatible impedance is used.

NickSeattle posted:

...

I can imagine that not being isolated from the pot might impart noise, maybe when the knob is turned, even if the output level were fixed. That would be bad during recording, but only a momentary annoyance in a whole-house distribution scenario.

... 

 

Due to the low output impedance of the source component or pre-amp, this is very unlikely to occur.

NickSeattle posted:

...

Even yet, I cannot infer the precise differences these distinctions make.  Still guessing.

Looking forward to finally getting this!  

Nick

Excellent!  Many thanks, Huge!

Nick