Optimod 8200 Quick Question

[gettinbyagain]

I have an 8200 running on a Top 40 station as a backup (and since we are doing work on the main tower / xmitter / audiochain etc. I have to remain on this for a bit) and it sounds good! I have one small problem, if we are in spots or have material with not much bass in it, the next big bass 'kick' from a rhythmic song sounds like overdrives something before the limiter / agc kicks in to get it undercontrol. Once it kicks in, it sounds fine!
Any ideas?

 

[weskeene]

I've heard that before too. You're hearing band 1's relatively slow attack. The solutions are few since the 8200 doesn't have "factory level" controls. Two options:

1) Lower the bass clipper threshold a little bit. It won't make the thump not happen, but it might keep your listeners' speakers from getting blown.

2) Use a preset that includes the faster MB release settings. I specifically say to use a preset that includes a faster MB release, but that preset will be tuned with correspondingly faster MB attack times. I don't have inside knowledge about what parameters get tuned when you flip to a new preset, so YMMV on that last suggestion, but it's worth a try. I have definitely noticed stations that run with MEDIUM-FAST do not have the thump issue as much. I used to run a rock format on slow, and it took me forever to get rid of "the thump".

 

[OKCRadioGuy]

AGC Drive = 12
AGE Release DB/SEC

 

[OKCRadioGuy]

Try this:

AGC Drive = 12

AGE Release DB/SEC= 7
Multiband drive= 14

multiband release=med fast

multband clip= +.06

Low Bass Boost= 2p+2

Mid Bass Boost= 0

Presence DB= +.05

Brilliance DB=0

Final Clip Drive= +.9

Gate Threshold

DB= OFF

HF Clipping= +1.0

DJ Bass Boost= OFF

Bass Coupling%=0

Downward expantion threshold= off

30Hz HPF= On

AGC= ON

Bass clip threshold DB = -6.0

Phase Rotor = IN

Band 1 Mix out= -.2

Band 2 Mix out= +.7

Band 3 Mix out= +1.7

Band 4 Mix out= +1.7

Band 5 Mix out= +.4

Band 3/4 coupling= 20

 

[gtomas]

Use a preset that includes the faster MB release settings. I specifically say to use a preset that includes a faster MB release, but that preset will be tuned with correspondingly faster MB attack times. I don't have inside knowledge about what parameters get tuned when you flip to a new preset, so YMMV on that last suggestion, but it's worth a try. I have definitely noticed stations that run with MEDIUM-FAST do not have the thump issue as much. I used to run a rock format on slow, and it took me forever to get rid of "the thump".

Excellent advice from Wes!

It's highly likely that presets with faster release times and heavier, denser processing, also employ faster attack times.


Regards,
Goran Tomas

 

[stha]

Just try to add more Bass Coupling in the AGC.

 

[mp3RadioGuy]

I’d find out what original preset you’re using first and what the “less more” setting is.
Remember your adjusting timing parameters with the “less more” that you can’t see but can hear. A higher “less more” setting = faster compression and limiting for a given preset. You may just need to increase your less more setting. I’d run a 7 or 9 with that format.

The 8200 can be a damn fine sounding box with the right tweaking.

 

[weskeene]

A couple other posters touched on another good idea, which is to increase bass coupling. In the 8200 you can't do that in the AGC (it's locked at 100% effectively). However, band 2->1 coupling is adjustable, and you may be able to knock out some thump by turning it up.

Be aware, it will hurt your ability to have low bass on music that lacks it, so try 5 or 10% increments.

 

[stha]

A couple other posters touched on another good idea, which is to increase bass coupling. In the 8200 you can't do that in the AGC (it's locked at 100% effectively). However, band 2->1 coupling is adjustable, and you may be able to knock out some thump by turning it up.

Be aware, it will hurt your ability to have low bass on music that lacks it, so try 5 or 10% increments.

I'm not sure for the older firmwares but the AGC Bass Coupling control is ajustable from 0 to 100% in the 8200v3. The only other available coupling is the 3&4 band at the limiter sections.

 

[BROADCAST]

The only bass coupling adjustment on v3 software is band 1 to band 2 % coupling ,ie 50% coupling forces 50% of band 2's limiter control to add to band 1 control.

There is no agc coupling of the master to bass available,only the built in factory set coupling(if it exists).

If Orban has fixed coupling of the agc's master band to bass band,i suspect this may be 25-30% ,but it would be nice to know from Bob himself !

 

[stha]

You're 100% right, I didn't used a 8200 since a long time...

 

[weskeene]

To answer an earlier post, the AGC bass coupling is about 100%, fixed in the 8200. Somewhere in the manual (or in Bob's comments long ago) that was stated pretty clearly. I say "about 100%" because Bob is often known to say 100% coupling doesn't sound good, and something lower like 80% is usually "close enough". When 100% is really used, you can actually get more low band GR than should really be happening.

Come to think of it, this may have even been covered in the 8100 manual when describing where to set the 2 band coupling at.

Wes

 

[satech]

I have an 8200 running on a Top 40 station as a backup (and since we are doing work on the main tower / xmitter / audiochain etc. I have to remain on this for a bit) and it sounds good! I have one small problem, if we are in spots or have material with not much bass in it, the next big bass 'kick' from a rhythmic song sounds like overdrives something before the limiter / agc kicks in to get it undercontrol. Once it kicks in, it sounds fine!
Any ideas?

Alas, the infamous 8200 "burble bass"! Combined with the grungy sound of the early Omnias in the mid-'90s, it actually made me think my receiver's FM tuner was somehow broken, because it sounded awfully distorted on a lot of stations. And don't forget around that time, when everybody started sending their commercials via very low bit-rate MP2s and MP3s, making them sound like absolute garbage on the air! Finish it off with the terrible sounding early digital cell phones, and it's a wonder we ever survived the "digital revolution" of the '90s without making our ears bleed!

 

[BROADCAST]

I have a feeling that master/bass agc coupling may be lower than 100%,reason being in 8100 use 100% would cause too much bass loss due to the additive effect as weskeene points out.

It may be possible to test this even though you can't see the bass band of the agc.
I will test my theory and post back the results.

Also does anyone know if the signature series uses a higher software version than v3.0 ?
Reason i ask is that there was talk of extra presets compared the the normal 8200,is that correct ?

 

[rorban]

To answer an earlier post, the AGC bass coupling is about 100%, fixed in the 8200. Somewhere in the manual (or in Bob's comments long ago) that was stated pretty clearly. I say "about 100%" because Bob is often known to say 100% coupling doesn't sound good, and something lower like 80% is usually "close enough". When 100% is really used, you can actually get more low band GR than should really be happening.

Come to think of it, this may have even been covered in the 8100 manual when describing where to set the 2 band coupling at.

Wes

Given that I worked on 8200 development more than 21 years ago (!) I don't 100% recall where we ended up setting the AGC bass coupling, but I believe that it was close to 100%. We were using the same principle that originally drove the 8100's master/bass architecture -- allow the compressor to operate wideband most of the time except when there is a lot of bass, at which point the bass compressor will kick in to prevent bass from pumping the midrange.

Bob Orban

 

[OKCRadioGuy]

WOW! The 8200 is a 21 year old design. Time gets away from a guy....

 

[chriscollins]

WOW! The 8200 is a 21 year old design. Time gets away from a guy....

Doesn't it? I was going through some songs to build a gold list for a CHR I program and had to stop myself, because I was jamming out to a 20 year old song (thinking it was from 7 or 8 years ago).

What's even more amazing is how durable all of those products are. I think about my 8100/XT2's and STL's that just run and run. The big difference was lightening could pop an 8100 and you could probably have it working in some form by the afternoon. If it pops and 8300, it is going back to the factory.

 

[BROADCAST]

To answer an earlier post, the AGC bass coupling is about 100%, fixed in the 8200.

I have done some tests and the results seem to indicate master/bass agc coupling is close to 100%.

With 5 band mode,agc on,and gate off,and all bass boost,mid bass boost and bass coupling all set at 0db and 30hz hp filter out,i set the processor so that a 20hz tone in to the processor at -10dbfs caused band 1 limiter to show 15db g/r (agc showed no g/r),then added a 10khz tone (also at -10dbfs)as well,this initially reduced band 1 g/r to reduce by 6db(agc now showing 15db g/r),so this would indicate 100% master/bass coupling.

 

[gtomas]

With 5 band mode,agc on,and gate off,and all bass boost,mid bass boost and bass coupling all set at 0db and 30hz hp filter out,i set the processor so that a 20hz tone in to the processor at -10dbfs caused band 1 limiter to show 15db g/r (agc showed no g/r),then added a 10khz tone (also at -10dbfs)as well,this initially reduced band 1 g/r to reduce by 6db(agc now showing 15db g/r),so this would indicate 100% master/bass coupling.

You would only need to apply the tone in the "master" part of the spectrum (above 200 Hz). If it's 100% coupling, the GR of the bass band should be the same as the GR of the master band - they are tied together and act as a pseudo wideband unit. If you would then add a tone in the bass part of the spectrum, the bass band should take more GR than the master band.


Regards,
Goran Tomas

 

[BROADCAST]

Goran,
As the bass band of the agc cannot been seen how would you calculate the % coupling using your method ?

Paul.