J99's clipping before my AD (MH2882) *SOLVED*

[niccolo]

Hi,
I've recently acquired a pair of used J99 modules.
The sound is ok but i've noticed that they both saturate 9dB before my AD frontend (Metric Halo 2882).
The AD converters are set to accept a +4 line input.
Tomorrow I'll post some more details, in the meantime are there specific troubleshooting measurements i could do?

thanks in advance

niccolo

[tpryan]

Make sure the regulators are set to provide maximum headroom. The actual voltages will depend on the ICs installed, but even at +/-18v you should get +22dBu before clipping.

Try padding the input signal and using more preamp gain.

[niccolo]

Ok, I'll download an assembly instruction and check the regulators..
Both units have Hardy IC's.
The signals fed to the unit while clipping were quite low in level, requiring more than 12 o'clock gain setting to sound distorted, but sill the distortion came before my AD reached 0dBFS.
The more I write about this, the more I feel that my understanding of the inner workings of these units is very scarce. I'd really like to gain some more insight on all of this..
Could it be that the units I have got were designed or regulated to work with an older power supply? My PS is quite recent (december 2007).
Where on the board can I find clues about what rev model these units might be?

Thanks

[niccolo]

Ok, just to get things straight
This is NOT an SCA problem and is easily solved if you follow this link
https://www.mhsecure.com/faq/index.php? ... %20preamps