AES48 , is there a test to determine?

Yes.


If you have an amplifier with a single-ended input, use an XLR adapter that connects only to pin2 and pin1 of the XLR output of the preamp. NOTE: pin 3 should **not** be connected for this test. Connect to the amplifier and listen to the result.


If it is free of buzz or hum, the preamp does not support the standard. If it does have hum or buzz, this is because the circuit is incomplete (pin 3 isn't connected).


A balanced source ignores ground and does not reference it- this is why you get the buzz with this hookup. In a balanced system the pin 2 signal is created with respect to pin 3 and vice versa. In the old days (and still today) this was/is done with an output transformer. That is why a lot of pro-audio studio gear has output transformers even though it might be solid state.


A quick and dirty, less accurate means of making this determination is if the output of the preamp has both RCAs and XLRs and there is no switch for going from one connection to the other, it likely doesn't support the standard. But if you have a DVM, you can measure for continuity between the center pin of the RCA and the pins of the XLR. If any have direct continuity and there is no switch as mentioned, then the standard is not supported.

@koestner Just as an FYI, I used the Benchmark StarQuad cables between the HPA4 and the AHB2 amp. Benchmark refers to these as professional grade cables because they carry a signal at 24dBU+. Whatever, the case I tried different XLR's between the components, including the Benchmark DAC3B and the StarQuads were just as good as anything I tried.

For my sources into the HPA4 (other than the DAC3B) I am using Audience AU24SE XLR and RCA. Those seemed to benefit from the more expensive Audience interconnets.

YYZ,

It was partially your high opinion of the HPA4 that lead me to try purchase one. Since the HPA4 is AES48 even though it has both balanced and single ended outputs without a switch (please comment Ralph) I was concerned about the Schiit Yiggy and the PS Audio M700's. I want to get 2 good XLR cables. I'm thinking of Audio Envy. They have 2 types of XLR cables. One the "GL" series seems to be for equipment that supports AES48 and their other line the "4:3" for those that do not. But, if my DAC and amp do support AES48 then it seems like the Benchmark XLRs will be just fine at less than 1/2 the price.

Ralph ... thank you for the "test" procedure, but I don't think I understand exactly what you mean. Does anyone know if the Yiggy DAC, or the M700 Ice Amps conform to the AES48 standard?

Thanks to all.