c24 pres are too hot and crazy faders...

[thesoundwells]

Hey,

We have been encountering some significant issues with the C24 console at a studio I'm freelancing for. The studio is running PT11 with a c24 and a fire face ufx. Ill dive in to explaining a few things, but let me know if you need anymore details :)

Faders
Many of the motorised faders have a mind of their own. With a protools session loaded many are not synced, and a few sporadically glitch/move. In the utility mode under ‘tests’, they are even worse. The attached videos show the problem in ‘vegas mode’ and in ‘group test mode’.

I have performed the following troubleshooting for this;
- Power cycle
- Recalibrate the faders in utility mode
- Reset firmware and reloaded in Protools session as described on DUC

These did not fix the issue and leads us to believe it could be a hardware issue.

PREAMP GAINS
Particularly worrying is the amount of signal at the preamps. This is the signal chain currently being used. Microphone>Multicore>DB25 snake>C24 Mic intups>C24 Preamps>C24 Line outputs>DB25 snake>RME Fireface>USB to Protools.

The Fireface UFX takes care of conversion for channels 1-8, and a SM Pro converter linked to the UFX by ADAT handles Channels 9-16. The UFX is set to +4 dB (it has a ‘low gain’ option for each channel, but when enabled does very little to the signal level).

The issue we a having is the amount of gain generated by the preamps before they are even turned up. The following test was conducted with 3 different microphones. For each microphone the preamp level on the c24 was turned completely down (hard anti clockwise). We placed a mic in the centre of the studio and strummed a acoustic guitar at 1m away from the mic. With no gain added on the preamp the levels were at -14 db (digital). As a room mic for drums both mics clipped straight away. Here are some recorded samples (straight into protools no processing) of the the two condensers with no gain applied at the console. We also used a sm58 to test a vocal and it too returned and level way too hot.

This is an issue which has been present in the studio since the desk was installed. The previous engineer has been using line attenuators on each mic input, and unto -40db in some cases. Its worth noting that the channel meters on the c24 also clip red, but we can’t find if these meter the preamp levels or the return levels from protools???
Any insight/troubleshooting into these problems would be much appreciated!


cheers

Ash

[Bill Denton]

The preamps on the early C|24's were way too hot for recording drums, so a 20db non-switchable pad was added and now they're not hot enough in a lot of cases.

You'll find more info on this subject at: http://duc.avid.com/showthread.php?t=303896

[YYR123]

Originally Posted by Bill Denton

The preamps on the early C|24's were way too hot for recording drums, so a 20db non-switchable pad was added and now they're not hot enough in a lot of cases.

You'll find more info on this subject at: http://duc.avid.com/showthread.php?t=303896

Good Find Bill.....

[jgrooms]

Originally Posted by thesoundwells

Hey,

PREAMP GAINS
...

The issue we a having is the amount of gain generated by the preamps before they are even turned up. The following test was conducted with 3 different microphones. For each microphone the preamp level on the c24 was turned completely down (hard anti clockwise). We placed a mic in the centre of the studio and strummed a acoustic guitar at 1m away from the mic. With no gain added on the preamp the levels were at -14 db (digital). As a room mic for drums both mics clipped straight away. Here are some recorded samples (straight into protools no processing) of the the two condensers with no gain applied at the console. We also used a sm58 to test a vocal and it too returned and level way too hot.

Your best friend with the C|24:

http://www.fullcompass.com/product/3...FVKIfgodoD8AJA


I still have no idea why a pad was not included with this controller. I curse everytime I use the onboard preamps.

[DetroitT]

"...Many of the motorised faders have a mind of their own. With a protools session loaded many are not synced, and a few sporadically glitch/move."
Pro Tools 11 updated Firmware after reset?

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