Headamp Blue Hawaii Special Edition - Page 227

The quality of the output stage in the source is far more important than the type of connection you use.  Running single ended adds a tiny bit of distortion, that is true of all amps that split the phase in any way.  It is a lot better though than the army of sources out that that have SE output stages and very dodgy ways of generating the XLR outputs from that. 

Quote:

Originally Posted by spritzer 

The quality of the output stage in the source is far more important than the type of connection you use.  Running single ended adds a tiny bit of distortion, that is true of all amps that split the phase in any way.  It is a lot better though than the army of sources out that that have SE output stages and very dodgy ways of generating the XLR outputs from that. 

How the BHSE was able to accomplish this Birgir?  A transformer or an op-amp?  I notice the volume was a bit lower on single-end compared to balanced input.

No opamps or transformers, just a fully differential design with high gain.  Normally single ended output has half the voltage of the balanced so it will be a bit lower in volume. 

Quote:

Originally Posted by spritzer 

No opamps or transformers, just a fully differential design with high gain.  Normally single ended output has half the voltage of the balanced so it will be a bit lower in volume. 

I meant taking SE signal and converted into a balanced signal.  thxs

Yeah, I know.  There is no phase splitter, it's just the natural design of the amp that handles it.  Same as the Stax amps. 

Quote:

Originally Posted by spritzer 

The quality of the output stage in the source is far more important than the type of connection you use.  Running single ended adds a tiny bit of distortion, that is true of all amps that split the phase in any way.  It is a lot better though than the army of sources out that that have SE output stages and very dodgy ways of generating the XLR outputs from that. 

Hello spritzer, and thank you again for your contribution. Reading your next sentence, I suspect that dodgy ways of using XLR input connectors also exist with cheap destination devices (essentially amps) that haven't a balanced toplogy at all. Any opinion about this? If you know some, canyou report them?

There are plenty of amps that are "lacking" in this regard.  One example would be the Bryston headphone amp which takes both the XLR and RCA sockets into the same circuit where the input is summed for XLR, fed into a normal stereo volume control (thus not balanced any more) and into the amp channels which are stacked, one is driven off the output of the other.  This causes a time delay effect.   There are many other amps that are just as bad, even some obscenely priced, but naming them would just make the manufactures freak out and have my post removed. 

I think you may be hyperventilating a bit there - a 30 yr old TL072 used as a phase splitter/inverter has < 100 ns delay, equivalent to ~ 0.001" of air path delay - and we can afford do to better with mere decade old, 2-5x faster "audio" op amps

full differential in/out circuits can be great schematic "eye candy" - but lots of pro equipment will be using op amp diff-to-se converters, processing single ended signal internally and send to op amp diff transceiver output

Whitlock at Jensen Transformers warns that even very good audio line transformers have trouble with high frequency common mode to differential conversion - the very best monolithic can beat audio transformers there

choosing intelligently from today's better, available full complementary BJT isolated process op amps targeted at medical imaging, telcom A/DSL and other demanding markets, modern op amps, using composite circuits where necessary, can beat discrete SS audio signal processing designs anywhere op amp noise, I,V  limits allow - which is most audio line level/interface applications - on objective measures of "accuracy"

I like fancy aluminum.

May God hear you

and support us in our wait

I'm not listening stats anymore until my BHSE is in front of me.