Question

Hello all,
[My sincere apologies - I've Edited for Clarity]

I am using 2 daisychained Quantums, with Studio One Pro, Faderport16. My L/R main outs from the Quantum go into a sub, which in turn go into the main inputs on the Monitor Station v2. Out of the Monitor Station V2 CUE outs I go to an ART HeadAmp6 Pro. Everything goes well until it gets to my Headphone amp - I can get virtually no clean signal through the Headphone amp and wondering if there is a setting I am missing, or is it literally that my brand new headphone amp is faulty.  So far I have tried:

1) CUE outputs from Monitor station to 1/4" Main L/R on Headphone amp
2) Line out on Monitor Station to 1/4" Main L/R on the Headphone amp
3) Mains out from Quantum directly into the 1/4" Main L/R on the Headphone amp
4) Headphone out from front of Quantum with Y splitter and into Main L/R of Headphone amp
5) Headphone out from headphone jack on Monitor station with Y splitter into the Main L/R of Headphone amp

Every config it just sounds buzzy and like there's not enough signal to power the headphones (AKG K702), yet when i jack my cans into the monitor station, or the quantum, it's crystal clear.

All the outlets in my studio are isolated grounds, but even still, I tried plugging into a regular outlet with same results?

Is this a simple case of bad gear (the headphone amp), or I've configured something wrong somewhere?

Thanks very much for any help,

Guitardron.

Answer 1

Hello everyone,

I wanted to put this question formally to rest and report that this was indeed an issue with the headphone amp. After the great thoughts that were posted here, it seemed to point that there was an issue with the HPamp itself.  I created an RMA and sent it back. After several weeks - the result was a repaired HPamp, and I'm happy to report that it runs like a champ. 

The root cause you might wonder? It was a broken ground on the input PCB that caused the issue.

Thanks again for the input! 

Answer 2

It sounds like a signal level issue. I'm confused why the same devices are connected to both the in and out of your headphone amp. I would expect the outs to go directly to your cans. Maybe I'm missing something in your explanation. The way its wired up just doesn't sound right... and the sound quality you're getting seems to bear that out. The distortion is from a too hot signal overdriving an input (amp).

Another important distinction that people often overlook--headphones come in varying impedances, from very low cans for low power devices, such as cellphones, to high impedance cans driven by mixer boards. The best example that comes to mind are Beyerdynamics 770 headphones. You'd want the 32 ohm for your cellphone and the 250 ohm for your mixer. Matching the correct impedance headphones to its source is an important consideration.