Are You Happy With Your Phono Preamp?

I upgraded a couple of years ago.  I trialled in my system with small Boulder and van den Hul The Grail SB.  I have had ARC phono amps before but I didn't look at the Ref3 because it can't be run fully balanced.  Why not?  Earlier ARCs had fully balanced options like the PH2 that I had for many years.

The Boulder sounded grainy, HF heavy and digital to me and tiring to listen to.  Very disappointing after the widespread review praise.  This wasn't a very long term trial.

The vdH was very natural and detailed with a good soundstage.  In my view value beyond its price.  I am very happy with it.  This is a sleeper.  Get a listen.  I have no connection with vdH other than as a happy customer.

@cleeds 

Thank you.

But I still cannot see how it can be fully balanced if it has only phonos for inputs.  If phonos can be balanced, why does it need XLRs for outputs?  And why do ARC included XLRs in and out on the Ref pre-amps?  And on earlier phono amps like the PH2 that I used with pleasure for 20 years.

All fully balanced phono amps offer XLRs for both inputs and outputs.  And, as you say, the ARC Ref preamps (I use a Ref 6 and have favoured ARC preamps in the past) include XLRs for input and output that I use as I want to run fully balanced throughout.

@cleeds 

It isn't FULLY balanced.  Whilst XLRs are an option for the output, the input is phono plugs only with two wires only.  There is no separate earth.  The earth must run on one or other of the two signal wires.

When I say fully balanced I don't mean artificially balanced using differential circuits.

@cleeds 

Perhaps a bit like the 'anticipator circuits' that Krell built from the late 1990s after they stopped selling pure Class A and claimed their Class AB amps were just like Class A.  I didn't believe that either. 

Yes I am very well aware of what ARC say. I was involved a couple of years back with a debate here about this statement by ARC when I was auditioning phono amps for my upgrade.  Some posters said it is not fully balanced.  Others accepted ARC's statement.  I concluded that it could not be certain the ARC Ref 3 is fully balanced.

I think both companies might be trying to blind us with their science.

@cleeds 

I think we shall agree to differ.

@mulveling 

Thank you for these elaborations.

I understand what you are saying, but that is exactly how tonearms were wired to amp inputs before there were balanced domestic set-ups e.g. my first stereo system in the mid 1960s (balanced started in studios where they had long inter-connect runs).  So what has changed to make that connection pattern balanced now?  Note in this set-up the earth is common to both channels, no separate earth for each.

So with that historic pre-balanced pattern I am inclined to think the ARC Ref 3 is not fully balanced..  I was involved a while back here in a thread where a piece was specced as 'fully balanced' but posts were saying it was not 'fully balanced'.  Some while back I had some leads made up with XLRs on one end to suit my tonearm output and phonos on the other to input to a phono only phono amp.  Since then I have decided not to go that way.

I don't pretend to know the answer, but in an environment where some say so -called fully balanced amps are not, I prefer to see XLRs on both sides.

By eliminating the XLRs they once put on their top phono amps ARC may have lost a sale here as I decided not to dem it.

I used the top Stax headphones and dedicated amp when I lived in an apartment from the mid 1990s.  They were awesome. Even if single ended - I have no idea with that five-way single connector.   I ought to get them out again and have a listen.