Rossini output XLR vs. RCA revisited

The +20 year love affair with my Naim 552/500 has ended and a new pair of DarTZeel separates have been warming up at Chez Gregg’s house (thank you @all2ofme ). I would like to revisit the perennial question of XLR vs. RCA outputs on the APEX Rossini.

I am in the process of returning my Chord Music cable for re-termination and need to decide how to terminate the Rossini end - XLR or RCA. DarTZeel prefers single ended RCA at their end. The cable will not be balanced - it will be single ended either RCA/RCA or XLR with wiring to RCA.

Is there some reason to have a Rossini XLR > DarTZeel RCA cable made up? Imho utilizing XLR out of the Rossini is pointless as the cable will be single ended and not balanced.

Perhaps James or Phil can comment @James @Phil and, if they recommend XLR/RCA, provide wiring instructions I can forward to Chord.

Best
Gregg

1 Like

I think, no, keep it simple RCA/RCA. In case of XLR/RCA, there is no technical complexity involved, just that one pin on XLR side will not be connected and just a pair of wires will be run.

1 Like

Not with you Gregg. Is this a balanced or an unbalanced cable? I assume the former because there is no way to make a single ended cable (two conductors, signal and ground) balanced (positive, negative, ground). The only** benefit of balanced connections is that they are balanced. The mirror image between the positive and negative means that any common mode noise cancels itself out. Using a balanced cable (and therefore connectors) in unbalanced mode (signal referenced to ground) has no advantages whatsoever. The darTZeel amp is single ended which is why it doesn’t offer balanced inputs. So single ended from the Rossini is the way to go. And if your Chord cable is single ended (two conductors instead of three) you have no option anyway.

** there are arguably other benefits of balanced, such as that the shield breaks simultaneously with the signal, but these have no bearing on sound quality.

1 Like

What is said is normally the case with the only objective consideration being the comparative rejection of parasitic noise. However in connecting balanced outputs to single ended inputs with dCS components there is a further issue. The circuits of balanced or single ended outputs are not the same. In many competitive products the single ended output is derived from the balanced circuit. However with dCS the balanced circuit is a discrete component based design, single ended an OP amp based design. Many have a subjective preference for the sonics of the balanced design even if the subsequent single ended input cannot take advantage of the improved noise rejection of a balanced interface.

I am aware that @Dunc has been loaning an XLR/RCA cable set so that fortunate recipients can make up their own minds. Perhaps he has a comment? BTW were you using the Rossini single ended to the old Naim amps?

2 Likes

Gregg, I believe the answer hasn’t changed from what’s listed in the dCS FAQ (it applies equally to the Vivaldi, Rossini, and Bartok);

In other words, where possible, use the Balanced outputs.

The appropriate wiring instructions (and warnings) are also in the Rossini manual;

2 Likes

Gregg,
I came from Naim as well (252/ND555/250) and find inner peace with Nagra :wink: so what DarTZeel are you on now?

I didn’t know this. Thanks @PAR and @anupc for the enlightenment. My comments about balanced vs unbalanced connections hold true but in dCS equipment there is apparently a big difference in the output stages that drive them.

Nevertheless to drive a single ended input it appears that even dCS is recommending using the single ended output, so in my ignorance I was still actually right.

1 Like

Thank you to everyone for the replies!

@struts001 my Chord Music cable is single ended - RCA out to DIN (for my previous Naim 552). I have flexibility with my dealer if I needed to change it out.

Pete @PAR The cable was used with my pre dCS streamer, a Linn Klimax DS, where RCA output from that player was used to go into the 552. It then moved over to the Rossini where I continued with the single ended output to the 552. Naim, as with my new DarTZeel, are not balanced in design.
When many of us were playing with Dunc’s cables we were going RCA out from the Rossini into the XLR input of the 500 amplifier. Even though the 500 has XLR inputs - they are not balanced. Naim simply use an XLR plug for the connection - it remains single ended.

@Anupc I think you hit the nail on the head with that post from the manual. It sounds like the Rossini may not be happy going balanced to unbalanced.

It sounds like I will soldier on as I always have been doing - RCA out from the Rossini

@T38.45 Just like Ben @all2ofme DarTZeel pre NHB-18NS (mk2) and amp NHB-108 model two. I demoed the super integrated CTH-8550 and was so convinced I decided to make the leap to the separates. Knowing myself, after +20 years on the Naim upgrade merry go round, I knew it would only be a matter of time before my mind started to wander. I am glad I decided to take care of the upgrade itch at the very beginning.
I have a feeling I may subscribe to what several have written about DarTZeel…they will be one’s “forever” components.

Best to everyone
Gregg

4 Likes

Colour me jealous @glevethan. While I have heard the darTZeels a couple of times at shows I find it is almost impossible to draw conclusions in such poor rooms and turbulent listening conditions. What can I possibly tell about a system playing Diana Krall at 130dB in a room with very little treatment where one wall is 20m^2 of glass and people are constantly coming and going and talking to each other? I would love to hear them in a properly optimised and tuned home system under optimal conditions. Maybe I will just have to buy a ticket to New Zealand!

1 Like

Hi Gregg,

If you are going into an unbalanced input on an integrated / preamplifier / power amplifier then I would use the unbalanced output from the Rossini, if you are going into a balanced input on an integrated / preamplifier / power amplifier then I would use the balanced output … mixing unbalanced and balanced inputs and outputs using specially wired adapter cables really isn’t ideal.

If the DarTZeel only has an unbalanced RCA input then I would use the unbalanced RCA output from the Rossini.

Cheers

Phil

1 Like

Hi Pete,

Remember that Naim use XLRs on their NAP135, NAP145, NAP250, NAP300 and NAP500 but they don’t use the XLRs to carry a BALANCED audio signal, they run UNBALANCED audio over their XLR connections on those amps.

The only Naim pre/power that uses balanced audio connections is the Statement.

Cheers

Phil

You raise a good reminder Phil.

@glevethan Gregg, the NHB-108 Mk.II’s balanced input is significantly improved from the original - as outlined in Stereophile’s follow-up review - any reason you’re not planning to use the balanced input?

The major difference between the original NHB-18NS and the Mk.2 was the replacement of the transformer-coupled balanced inputs and outputs with a direct-coupled topology.

Hi Anup

Yes you are correct in that the MK2 version of the DarTZeel has significantly improved the balanced XLR connection. With that said DarTZeel are single ended by design (and by preference of the designer/owner) who is not a fan of balanced. I believe he goes into this in the white paper/technical explanation documents.

So yes there is a single XLR input on the preamp…however there are 5 single ended inputs. Sort of shows you where the designers preference lies.

Best
Gregg

PS I will have to ask Ben @all2ofme if he has played around with the XLR input on his pre. After all…he is responsible for getting me into this mess :rofl:

1 Like

Did you mean his series of Stereophile articles? (Or was there a separate Whitepaper? I can’t seem to find it).

I would like to use this thread to inquire about the output voltage of my Rossini Apex. If I set the output to 6V, what is the voltage output on RCA?

I’m using the 6V XLR to drive a power amp and intend to connect the RCA output to a subwoofer. If the RCA output is also 6V, this might overload my subwoofer’s input.

For a 2V output setting, I assume that both XLR and RCA outputs are 2V. Is that correct?

Thank you.

The 6V and 2V out both apply to XLR and RCA.

1 Like