Recording Forum

[vidrazor]

Hi folks, I just got this Tascam bugger, and there is a feature I'm not quite understanding called PEAK REDUCTION. It's strikes me as either half a compressor or AGC, where it will reduce a signal if it goes over some predefined threshold, but not boost it if it drops too low. This is a separate and different function from the unit's AGC and limiter settings. The description given is thus:

"PEAK REDUCTION:
The input volume is reduced automatically to an appropriate level when excessively large signals come in. This allows recording level setting to be performed easily. The recording level can be raised manually if required."

It then proceeds to give this "tip" which has me confused:

"TIP
When recording live performances, for example, test for peak reduction may be performed before actual recording. Select the peak reduction mode in recording standby, and maximize the recording level. As a test performance is given subsequently, the input gain for recording is reduced to an appropriate level to meet the input signals, and an optimum recording level for the performance is set. Recording will be stored at this recording level if this mode is disabled before starting recording. Otherwise, the recording level will continue to be controlled automatically during recording. It is also possible to store the recording in the limiter mode after automatically setting the recording level in the peak reduction mode."

So how would you know if your gain is optimized if this thing is on and reducing an over-gained signal? What if signal levels in a recording environment/performace drop after a while? Then your gain would be too low, no? I can see perhaps setting your gains with this thing OFF, then turning it on afterwards, but then you can suffer the same fate if SPLs rise and drop. Seems a limiter would be a better choice.

So, am I missing something obvious here? Is this a half compressor/AGC? Is this really a useful tool somehow? I just don't get it. Thanks for your input (no pun intended) on this.

[WRGKMC]

Peak reduction is usually limiting. Slighty different than compression because it doesnt
bring up the vallies like a comp does, it only limits and levels the peaks.

[vidrazor]

No, it's definitely not limiting. It reduces levels and KEEPS them at that reduced rate. This to me seems problematic because if any sort of loud transient comes through, the levels get dropped, and you are now recording the rest of the session at reduced levels. This function doesn't strike me as very intelligent, IMHO. I have decided not to use this feature at all. I'm not sure if the limiting circuit in this unit is analog (desired) or digital (useless), but I'll have to try some sessions to see how it goes.

[WRGKMC]

^^^ But Thats exactly what a limiter does man. It limits peaks to whatever
threshold you set, and no matter how hard you drive it the peaks never go higher.

The thing with digital recording is you must "Never" go above 0db.
If you do, you get digital distortion. The limiter prevents this from happening
if you're running your inputs too hot. Otherwise the limiter shouldnt do anything at all.
If you're hearing a reduction tracking, your track levels are likely too hot.

Normally your individual tracks should be way down in the -12 to -14 range.
You should be no wheres near the point where the limiter is going to kick in, and
if you do keep your levels correct, then theres no need to use a limiter. The exception
may be drums. A snare for example has huge transients and a limiter can give you a hotter
sound at lower levels. Even then you can do all that when mixing.

I only use limiting when mixing or mastering. I never use any effects tracking
because they color the sound and cant be undone. If you're just slapping a limiter
on there tracking without a reason, I suggest you study your basic recording techniques.
Normally a limiter is used on the stereo mixdown. Its used mastering to bring the music
up to commercial loudness levels and make it sound professional. Used on solo tracks,
like say guitar thats already highly compressed can make the guitar sound awful in a mix.
it sucks all the dynamics out of the track and all its emotion in the process.

[Zooey]

Peak reduction, limiting, and automatic level control are all separate settings on that device. I would have to play with it to know what they really do. I think the automatic level control can adjust input gain up or down, but limiting is gain reduction only. The manual isn't particularly clear, is it?

[vidrazor]

I used the limiter in live situations where I never know where a band, or the sound man, is going to go.Unfortunately I got this reply from Tascam regarding the limiter in the DR-07:

"The Limiter is after the A/D converter, so it would be a digital process."

So it's essentially useless.

OT, is it me, or does this new forum software really suck?