Trying to get started with Lexicon Omega

[KEW]

I'm hoping to use REW to identify treatments necessary for my very modest bedroom studio. I'm using a Lexicon Omega usb interface, and I can't seem to get things to work properly. I've tried to calibrate the soundcard by connecting one of the outputs (it has separate L & R outputs) to one of the inputs (has 4 line inputs), but there appears to be no signal going through.
So for grins, I skipped ahead just to see if I can do any test at all, (using the old-style RS meter). But I can't find a way to disable input monitoring, so I get feedback when the levels are set anywhere high enough to be measured.

One strange thing, the suggestions I've seen for disabling input monitoring say to mute the line-in on the playback mixer. But my playback mixer only has faders for Wave, SW Synth, and CD Player (I'm using XP SP3). Oh, and there's no Record mixer at all.

Any help would be greatly appreciated.

Kevin

[brucek]

You're definitely going to have to solve the monitoring problem. The Lexicon isn't giving access to Windows to control the line in volume, and so that must be controlled using the Lexicons hardware or application software. Similar with the monitoring. This must be a hardware function that is either controlled directly with hardware controls on the unit itself or in its own application.

Don't waste time with skipping ahead. You must solve the soundcard calibration with a loopback cable first or you'll be wasting your time. I trust you used a TRS loopback.

Does REW see the card and any of its inputs and outputs in its devices pulldowns or is it only offering default status?

brucek

[KEW]

Thanks for the reply. I have searched for a way to disable the input monitoring, but apparently it's not a very common question for this device. I'm trying to contact Lexicon about it, but they're not terribly responsive.

If you have any other suggestions on how to solve that problem, I'm all ears.

Kevin

[blahblahguy]

I am having similar problems. any ideas ? BTW I have the on board audio disabled on my pc due to driver resource conflicts so the onboard card is a no go and I don't really have a good way to hook a microphone to it as all my units are phantom powered.The loopback Procedure "entirely useless on a decent audio card" cuases a serious feedback problem.

This device has very flat and decent quality preamps and 24b 48khz encoding. If there is a skew. It is small enough to not be of any imediate concern. I essentiall want to run some plots and see where my room is bad. But REW demans a stereo input "why ?" and I onyl have 1 mic thats properly calibrated. I see no need to buy 2 mic's but if I must I must.

Also on SP3 Win XP pro. The program does not seem to function properly. Sliders buttons etc do not move correctly. Is this do to my stripped down appearance settings ?

Lastly. Why is REW running on Java ?

[Wayne A. Pflughaupt]

All you need to use REW is a full-duplex sound card with line-level inputs and outputs that has the capability of turning off any monitoring function, and an SPL meter. That’s it. A Radio Shack SPL meter with our calibration file is accurate enough for measurements out to 3 kHz.

If you want full-range measurements out to 20 kHz, a mic with a calibration file (that can be loaded into the program) is needed, as well as a sound card with a mic pre amp (although an outboard pre-amp separate from the sound card can be used).

and I onyl have 1 mic thats properly calibrated. I see no need to buy 2 mic's

A calibration file is needed for your mic, that can be loaded into the program. If you have a frequency response plot of your mic, either from the manufacturer or whoever calibrated it for you, you can create a calibration file.

This device has very flat and decent quality preamps and 24b 48khz encoding. If there is a skew. It is small enough to not be of any imediate concern.

If you’re confident that your sound card is flat and needs no compensation file, then feel free to run REW without one.

But REW demans a stereo input "why ?"

Don’t know. I imagine it’s because the program was originally envisioned for home audio users, and most home computers use stereo sound cards.

Regards,
Wayne

[JohnM]

blahblahguy wrote:

The loopback Procedure "entirely useless on a decent audio card" cuases a serious feedback problem.

If you get feedback doing a loopback you have monitoring enabled or a mixer setting that is putting the input back on the output. Turn off the monitoring and set up the output mixer so the only signal it is getting is the test signal from REW.

blahblahguy wrote:

But REW demans a stereo input "why ?"

It doesn't. Javasound (in common with most of the underlying OS platforms) passes audio around in stereo pairs, but REW only listens to one input (the one you select in the soundcard settings panel) and it doesn't matter what you do or don't connect to the other.

blahblahguy wrote:

Also on SP3 Win XP pro. The program does not seem to function properly. Sliders buttons etc do not move correctly. Is this do to my stripped down appearance settings ?

It might be, if whatever changes you have made include a different windows theme the Java runtime Environment may not handle them correctly.

blahblahguy wrote:

Lastly. Why is REW running on Java ?

REW is written in Java because it offers a good degree of cross-platform portability between Windows, Linux and OS X.

[blahblahguy]

JohnM wrote:

If you get feedback doing a loopback you have monitoring enabled or a mixer setting that is putting the input back on the output. Turn off the monitoring and set up the output mixer so the only signal it is getting is the test signal from REW.

I can't. It is hardwire into the interface as a real time playback monitor of input.

JohnM wrote:

It doesn't. Javasound (in common with most of the underlying OS platforms) passes audio around in stereo pairs, but REW only listens to one input (the one you select in the soundcard settings panel) and it doesn't matter what you do or don't connect to the other.

is the code open source ? Would be a bit of a undertaking but making it ASIO compatiable might be a good idea as audio cards are really moving away from that standard.

JohnM wrote:

It might be, if whatever changes you have made include a different windows theme the Java runtime Environment may not handle them correctly.

REW is written in Java because it offers a good degree of cross-platform portability between Windows, Linux and OS X.

I use no windows themes. Thats the thing. All the fancy control profiles are disabled. No shading etc etc etc. It is a pretty hardcore audio PC no reason to muck things up with I don't use.

what is REW written before it gets compieled as a JAVA app or is it strictly a JAVA application ?

[JohnM]

REW is written in pure Java. It is not open source.