The Benchmark StarQuads are very good cables and I would not have looked at anything else except for the fact that I had to get my Audience cables upgraded due to damage of the AU24 and AU24e originals. They are a tiny bit better than the StarQuad on the short run between the DAC and preamp.
My SACD player and 2 FM tuners will get 3 foot AU24SE cables from this upgrade that yielded 5 cables from 1 very long AU24 and 1 short AU24e. I will set this all up next week when my rack arrives. I could sell all of these cables to buy a long XLR between the preamp and amp but it sounds like what I am doing is the next best thing.
One thing that I really should ask Benchmark, and I will when I buy 2 more pieces from them (HPA4 + AHB2), is if their gear works well with long XLR runs and "non-professional" grade XLR's. I been bugging them a lot already so I will pace the questions to them They use the term professional grade vs consumer grade (such as my AU24SE).
https://benchmarkmedia.com/blogs/application_notes/balanced-vs-unbalanced-analog-interfaces
STUDIO-GRADE BALANCED INTERFACESProfessional balanced interfaces generally operate with much higher signal levels than unbalanced consumer interfaces. This voltage difference gives these balanced interfaces a significant SNR advantage over unbalanced interfaces. Most RCA interfaces operate at a maximum signal level of +8.2 dBu which is 2 Vrms. In contrast, professional balanced interfaces usually operate at a maximum signal level of +24 dBu which is 12.28 Vrms. If you do the math (24 dBu - 8.2 dBu) you can see that the signal level is 15.8 dB higher on the professional-grade balanced interface. If the noise is the same on both interfaces, the balanced interface will provide almost a 16 dB improvement in the interface SNR.
But, balanced interfaces always require dual output buffers and dual input receivers. These additional active devices contribute some noise and this tends to reduce the SNR improvement by about 3 dB. Taking this into consideration, the interface SNR of a professional balanced interface is still about 13 dB better than that of an unbalanced consumer interface.
In addition, balanced interfaces provide rejection of many types of interference. This immunity to interference can provide a 50 to 100 dB reduction in these unwanted noises. This immunity to interference is usually more than enough to keep the interference inaudible.
Professional interfaces are more expensive to build. The high signal levels generally require the use of +/- 18 volt power supplies within the audio product. To save costs and reduce the power consumption, consumer products usually use much lower supply voltages. As a result, it is rare to find consumer audio products with balanced interfaces that can support professional signal levels. These products have dumbed-down balanced interfaces that operate at much lower voltages.
CONSUMER-GRADE BALANCED INTERFACESMany high-end consumer products have balanced interfaces, but they operate at a maximum level of 4 Vrms which is + 14.2 dBu. This is 10 dB lower than the level used in professional interfaces. This means that the 13 dB advantage provided by a +24 dBu balanced interface is reduced to just 3 dB when operating at a maximum level of +14.2 dBu. Consumer-grade balanced interfaces are definitely a step better than unbalanced interfaces, but the signal levels are too low for use in very high perfomance systems.
Benchmark D/A converters are equipped with professional-grade +24 dBu outputs. These outputs have 10 dB passive pads that can be engaged in order to drive consumer-grade 4 V balanced inputs. If you find you need these pads, it is a good indication that the downstream device is limiting the SNR performance of your system. Likewise, the AHB2 has a gain setting that supports inputs from 4 Vrms consumer-grade balanced outputs. Again, these consumer-grade devices will be the weak link in the system.
Check the specifications and look for balanced interfaces that support professional signal levels. Consumer-grade balanced interfaces may look like professional interfaces, but they do not provide the same level of performance.
