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modification Optimod 8100A
- Thread starter OPTIMOD 8100
- Start date
Re: modifacation Optimod 8100A
That is really an impressive number of mods you've done... And the results are obvious. I've compared your clip with the 8100/XT2 we're using on one of the stations, which is 20 years old and never been repaired, re-capped, re-chipped or even re-aligned (I've uploaded that clip as well). Sonically, your clip sounds cleaner, wider, bigger, with more bass and more depth. Ours is in comparison narrowed down, thiner and tinier. This was taken off-air from a live program. There are certainly some difference between the tuners we're using, but still, the difference is quite noticeable...
There's one thing however, that I like more with our processor. Obviously the texture is a bit different in terms of bass/high-end and it plays a part in this, but I find our processor to be more "dynamically alive". It's hard to explain what I mean by this but simply put, it outlines the micro-dynamic contrast in song more. I guess this is most obvious in the second part of the song where she sings "baby, baby..." three times and three times there's a brief pause before the impact. This is where I find our 8100/XT2 to emphasize the impact and drama, whereas with your settings the high-end is pushed a little bit back and everything goes softer and with less energy. But I guess that's just the matter of adjustment and once again, congrats on the mods you've done
It would be nice to hear how this clip sounds through some other 8100/XT2s or some other processors! I haven't had a chance to hear the (in)famous Prism-8100 combination, so if anyone has it on the table and has some free time...
Regards,
Goran Tomas
BROADCAST said:
That is really an impressive number of mods you've done... And the results are obvious. I've compared your clip with the 8100/XT2 we're using on one of the stations, which is 20 years old and never been repaired, re-capped, re-chipped or even re-aligned (I've uploaded that clip as well). Sonically, your clip sounds cleaner, wider, bigger, with more bass and more depth. Ours is in comparison narrowed down, thiner and tinier. This was taken off-air from a live program. There are certainly some difference between the tuners we're using, but still, the difference is quite noticeable...
There's one thing however, that I like more with our processor. Obviously the texture is a bit different in terms of bass/high-end and it plays a part in this, but I find our processor to be more "dynamically alive". It's hard to explain what I mean by this but simply put, it outlines the micro-dynamic contrast in song more. I guess this is most obvious in the second part of the song where she sings "baby, baby..." three times and three times there's a brief pause before the impact. This is where I find our 8100/XT2 to emphasize the impact and drama, whereas with your settings the high-end is pushed a little bit back and everything goes softer and with less energy. But I guess that's just the matter of adjustment and once again, congrats on the mods you've done
It would be nice to hear how this clip sounds through some other 8100/XT2s or some other processors! I haven't had a chance to hear the (in)famous Prism-8100 combination, so if anyone has it on the table and has some free time...
Regards,
Goran Tomas
Re: modifacation Optimod 8100A
We have yet to see a message from Modulomaxx here... He uploaded quite a few clips, some with obvious high-end hole-punching like the one you're talking about, but some other clips are interesting, to say the least. Too bad the most recent clips stops just when the song gets exciting Sounded good thus far.
So Mr. Modulomaxx, why not post a message here with little more info?
Regards,
Goran Tomas
BROADCAST said:
We have yet to see a message from Modulomaxx here... He uploaded quite a few clips, some with obvious high-end hole-punching like the one you're talking about, but some other clips are interesting, to say the least. Too bad the most recent clips stops just when the song gets exciting
Sounded good thus far. So Mr. Modulomaxx, why not post a message here with little more info?
Regards,
Goran Tomas
Re: modifacation Optimod 8100A
Hi Goran,
The settings i used were the same for all tracks,so propably not optimised for all the tracks.
Also as the xt2 density was a touch excessive,this would not help the effect you mentioned between yours and mine.
Also a point i mentioned before,the 8100's agc setting is set so that old cd's still compress to 10db,whilst new tracks compress to 20db!
Of course this setting is a bit excessive for new cd's,but for test purposes,it is a hassle to re-set!
The hole hf hole punching is a typical problem caused by processing before the 8100a.(of course not all,but most).
The problem i had with prisms was trying to keep the audio consistant from track to track.
U2's with or without you,is a hard track to process clean,this is where the 8200 has a very hard time!
By the way,my settings for the 8100a were release 7, bass coupling 1.
Xt2 settings were presence 1, brilliance 4, clipping 0.
Density was set to make band 4 hit 6db limiting.
Left and right filter out(on the 8100a meter),hits -1db very often,also peaks at 0db!
Goran,i can't see your uploaded clip,which one is it?
Hi Goran,
The settings i used were the same for all tracks,so propably not optimised for all the tracks.
Also as the xt2 density was a touch excessive,this would not help the effect you mentioned between yours and mine.
Also a point i mentioned before,the 8100's agc setting is set so that old cd's still compress to 10db,whilst new tracks compress to 20db!
Of course this setting is a bit excessive for new cd's,but for test purposes,it is a hassle to re-set!
The hole hf hole punching is a typical problem caused by processing before the 8100a.(of course not all,but most).
The problem i had with prisms was trying to keep the audio consistant from track to track.
U2's with or without you,is a hard track to process clean,this is where the 8200 has a very hard time!
By the way,my settings for the 8100a were release 7, bass coupling 1.
Xt2 settings were presence 1, brilliance 4, clipping 0.
Density was set to make band 4 hit 6db limiting.
Left and right filter out(on the 8100a meter),hits -1db very often,also peaks at 0db!
Goran,i can't see your uploaded clip,which one is it?
Re: modifacation Optimod 8100A
Indeed, deeper gain reduction in XT2 would flatten out transients...
I haven't heard it, but people who's opinion in processing I trust had similar comments to yours. But it would be interesting to hear how that combo sounded and why it was so popular
FWIW, my settings for 8100A are: release time 6, bass coupling 6.5, input set for ~12dB of master band gain reduction. XT2: density set for less than 4 dB gain reduction in band 3, clipping 0, presence 1, brilliance 3.
It should be near the top of the list (sorted by time) titled 'Tina Arena - 8100XT2 Radio 101.wav'
Regards,
Goran Tomas
BROADCAST said:
Indeed, deeper gain reduction in XT2 would flatten out transients...
I haven't heard it, but people who's opinion in processing I trust had similar comments to yours. But it would be interesting to hear how that combo sounded and why it was so popular
FWIW, my settings for 8100A are: release time 6, bass coupling 6.5, input set for ~12dB of master band gain reduction. XT2: density set for less than 4 dB gain reduction in band 3, clipping 0, presence 1, brilliance 3.
It should be near the top of the list (sorted by time) titled 'Tina Arena - 8100XT2 Radio 101.wav'
Regards,
Goran Tomas
Re: modifacation Optimod 8100A
I have uploaded the 8200 midslow track of Tina Arena test track.
Also i am currently uploading 8200 midfast track of the same,and also the Fm Ultramod and cp2013 comproc version.
The reason i uploaded both midslow and midfast versions is that the nearest multiband setting on the 8200,to the xt2 is midfast.
I prefer the midslow,the 2 settings are quite different on the 8200.
The settings of both are modified from the default presets,also i am using aes/ebu in straight off the cd player,so the background noise floor is very low.
This can also alter your perception of (lack of)breathing on the track.
I have done a few internal mods to the 8200,but nothing like the 8100a/xt2!
If you want the 8200's settings for both presets,let me know.
I have uploaded the 8200 midslow track of Tina Arena test track.
Also i am currently uploading 8200 midfast track of the same,and also the Fm Ultramod and cp2013 comproc version.
The reason i uploaded both midslow and midfast versions is that the nearest multiband setting on the 8200,to the xt2 is midfast.
I prefer the midslow,the 2 settings are quite different on the 8200.
The settings of both are modified from the default presets,also i am using aes/ebu in straight off the cd player,so the background noise floor is very low.
This can also alter your perception of (lack of)breathing on the track.
I have done a few internal mods to the 8200,but nothing like the 8100a/xt2!
If you want the 8200's settings for both presets,let me know.
Re: modifacation Optimod 8100A
Also just for reference i am currently uploading Paula Abdul Rush Rush 8200 midslow 2p+4 track,this setting i did delibrately to overhype the bass!
I normally use 3p+2 with the midslow.
On modulomaxx's tracks,the files clip at 0dbfs!
The problem could be is when the files are compressed.
The more an audio track is compressed,the greater the lack of peak control upon playing that file.
All fun. ;D
Also just for reference i am currently uploading Paula Abdul Rush Rush 8200 midslow 2p+4 track,this setting i did delibrately to overhype the bass!
I normally use 3p+2 with the midslow.
On modulomaxx's tracks,the files clip at 0dbfs!
The problem could be is when the files are compressed.
The more an audio track is compressed,the greater the lack of peak control upon playing that file.
All fun. ;D
Re: modifacation Optimod 8100A
Goran,
I am uploading the Tina Arena track from my tuner from the 8100a/xt2.
I have used your settings,and have set the xt2's bass eq to 4db boost(i am sure yours is similar).
Also i have a switch inside the xt2 that i can flick between standard xt2 or my combined mode,i left it in xt2 mode to match yours.
Apart from the bass,the rest of the balance should sound the same,except for the opamps etc.
I think it sounds excellent,you can clearly hear the difference in detail.
Regarding the 8200's test of the same track and Modulomaxx's dspx version,open up the files with soundforge etc,and carefully look at the beginning of the bass,notice the 1 cycle of higher peak level on the dspx version!
I suspect this is from the processor,as their is no obvious tell tale signs of pll bounce,which would show up as a dc offset after the event.
All interesting stuff!
Goran,
I am uploading the Tina Arena track from my tuner from the 8100a/xt2.
I have used your settings,and have set the xt2's bass eq to 4db boost(i am sure yours is similar).
Also i have a switch inside the xt2 that i can flick between standard xt2 or my combined mode,i left it in xt2 mode to match yours.
Apart from the bass,the rest of the balance should sound the same,except for the opamps etc.
I think it sounds excellent,you can clearly hear the difference in detail.
Regarding the 8200's test of the same track and Modulomaxx's dspx version,open up the files with soundforge etc,and carefully look at the beginning of the bass,notice the 1 cycle of higher peak level on the dspx version!
I suspect this is from the processor,as their is no obvious tell tale signs of pll bounce,which would show up as a dc offset after the event.
All interesting stuff!
Re: modifacation Optimod 8100A
He He.
all intersting stuff and funny !!!!, specialy making blind test.
my 4 last clips were recorded using AES/EBU output in FM mode@50us -1 dBfs and normalized to 0 dBfs!! the tracks Rush Rush & Expose sources are in mp3, too bad i know.
I think with the dspx unit it's hard to find a good result to combine in same time high Mpx power without distorsion, stable spectral energy and clean HF clipping, you have always to do a compromise, the limiter section is little bit strange. i have to say the dspx is only 4 band and anyway an interesting processor due his price but i prefer the xt2 clips result and efficiency.
the XT2 still has a lot of good points, easy to use, plug and play unit, stable, "Orban Sound" with loud bass, spectral energy controlled, low distortion.
here, in a big city with strong loudness war, there is one Xt2 unit on air with L/R output card feeding an O3T with other stations cascading O6 and IDT in front (+8.5 dBr!). one other radio station with XT2 L/R output feeding Aztec digiplexer on site, and one interesting station use an 8282 with digiplexer and sound almost the same at the XT2 with digiplexer, but for me the XT2 is not enough competitive with the other digital "big boxes", limited mpx power (+6dBr max), bad definition (like low sample rate), today, after 20 minutes i can't listen to the station using XT2 (same with 8200), i keep my XT and XT2 (led version) for my museum !
Broadcast, do you have microgen or audemat analyser to make your clips with your FM exciter, are your mods changing the FM deviation control ?
Cheers everybody
ModuloMaxx
He He.
all intersting stuff and funny !!!!, specialy making blind test.
my 4 last clips were recorded using AES/EBU output in FM mode@50us -1 dBfs and normalized to 0 dBfs!! the tracks Rush Rush & Expose sources are in mp3, too bad i know.
I think with the dspx unit it's hard to find a good result to combine in same time high Mpx power without distorsion, stable spectral energy and clean HF clipping, you have always to do a compromise, the limiter section is little bit strange. i have to say the dspx is only 4 band and anyway an interesting processor due his price but i prefer the xt2 clips result and efficiency.
the XT2 still has a lot of good points, easy to use, plug and play unit, stable, "Orban Sound" with loud bass, spectral energy controlled, low distortion.
here, in a big city with strong loudness war, there is one Xt2 unit on air with L/R output card feeding an O3T with other stations cascading O6 and IDT in front (+8.5 dBr!). one other radio station with XT2 L/R output feeding Aztec digiplexer on site, and one interesting station use an 8282 with digiplexer and sound almost the same at the XT2 with digiplexer, but for me the XT2 is not enough competitive with the other digital "big boxes", limited mpx power (+6dBr max), bad definition (like low sample rate), today, after 20 minutes i can't listen to the station using XT2 (same with 8200), i keep my XT and XT2 (led version) for my museum !
Broadcast, do you have microgen or audemat analyser to make your clips with your FM exciter, are your mods changing the FM deviation control ?
Cheers everybody
ModuloMaxx
Re: modifacation Optimod 8100A
Hi Modulomaxx!
Glad to see you here,with a voice behind the test tracks!
The dspx is regarded as a good box,far newer than my 8200,let alone the old trusty 8100a/xt2.
Of course the 8100a/xt2 cannot compete in loudness/distortion compared to the 06 and 8400 etc.
But people comment on how easy it is to listen to,as we know,you cannot get in to too much trouble with the settings.
I think many would aggree that the 8100a/xt2 has a certain "charm" factor.
As i have the digital i/o card in the 8200,i could set the aes/ebu out for flat,and record from it,so cutting out the stereo encode/tx/rx etc,but i prefer to compare with an off air tuner.
Incidentally my tuner is a Sony ST-SE700,with a few mods,this is the tuner i recorded the samples from!
The deviation is tightly controlled due to the safety clippers being a bit more active,but i have no composite clipper.
I have never seen any success using any other boxes,when using both 8100a and xt2 together.
Tell me,what was causing the top end limiting on some tracks(like the "sun",i mentioned)?
Hi Modulomaxx!
Glad to see you here,with a voice behind the test tracks!
The dspx is regarded as a good box,far newer than my 8200,let alone the old trusty 8100a/xt2.
Of course the 8100a/xt2 cannot compete in loudness/distortion compared to the 06 and 8400 etc.
But people comment on how easy it is to listen to,as we know,you cannot get in to too much trouble with the settings.
I think many would aggree that the 8100a/xt2 has a certain "charm" factor.
As i have the digital i/o card in the 8200,i could set the aes/ebu out for flat,and record from it,so cutting out the stereo encode/tx/rx etc,but i prefer to compare with an off air tuner.
Incidentally my tuner is a Sony ST-SE700,with a few mods,this is the tuner i recorded the samples from!
The deviation is tightly controlled due to the safety clippers being a bit more active,but i have no composite clipper.
I have never seen any success using any other boxes,when using both 8100a and xt2 together.
Tell me,what was causing the top end limiting on some tracks(like the "sun",i mentioned)?
Re: modifacation Optimod 8100A
I agree you you.
About the "Sun", all gate disabled for more mpx power and too much HF clipping for Rap/Rnb song that i didn't change for the clip.
i'm not able to make the recording with my BE50 Exciter, the power supply is faulty, and my old italian one is too bad.
ModuloMaxx
I agree you you.
About the "Sun", all gate disabled for more mpx power and too much HF clipping for Rap/Rnb song that i didn't change for the clip.
i'm not able to make the recording with my BE50 Exciter, the power supply is faulty, and my old italian one is too bad.
ModuloMaxx
I have modded dozens of 8100's and Prisms
Over the past 25+ years I have modded close to 100 of these units (and 8000's as well). The main problem with them is the quality of the negative power supply and the general quality of the chips and caps used within them. Bob Orban is a master marketer; he designed his units to slowly degrade over time, so when you compare his newest box against the older one, it blows it away! HALF of this is not because his new box is that much better-instead the older unit has degraded to the point where it's half as good as it was when new. In addition, he used TLO opamps in these-which were great in 1975, but suck in 2007!
In an 8100, replace ANY light purple or orange electrolytic caps on ANY card-they have long dried up. Replace the bass DC coupling cap (it's tantalum) with a nonpolar. The VCA's in these units are fine-if you look at how they're used, they live within the feedback loop of a 5534 opamp-audio does not directly pass through them. By the way, they're used in the stereo generator too-and properly adjusted you can get upwards of 55 db separation midband with this unit. The VCA's are a stock RCA product.
The problem with bass grunge in most units is caused by one half of IC-310 on cards 3 and 4 sitting there oscillating. It screws up the power of the half that the bass goes through. I discovered this YEARS ago and reported it to Orban, who told me I was crazy until they looked at a card and found NONE of the 3 pins on the opamp were connected to anything. It's easy to configure this opamp as a voltage follower with it's non-inverting input connected to ground (If you don't know what I'm talking about, then you shouldn't be playing with these cards at the component level). By the way, to my knowlege Orban never came out with a bulletin about this, though they fixed it on all cards from that point (around 1986).
The "multi stage crossover with imbedded bass clipper" on cards 3 and 4 was put there so Bob could get a patent on it. It's simply two single pole filters cascaded with two clipping diodes in between them. By the way-the unit sounds MUCH better with these diodes OUT!
The back to back caps (with a film across them) on the filter cards (8 and 9) need to be replaced with a single 100 uf nonpolar.
I also put additional power supply filtering everywhere. The .1 disc caps on each card's power supply input are USELESS. Put a decent film there. Also, an official Orban mod is to replace the 25 uf caps here with 100 uf ones. I also drop an additional 6800 uf in each power supply rail-it stiffens things quite a bit.
I have rebuilt three of these units within the past few months (with their Audio Prisms as well) and the stations that put them in were all BLOWN AWAY by how great they sounded. They tried EVERYTHING against them and kept coming back to the analog processing time after time. I've had PD's do the same thing over the years. They all also use a MSI clipper-but the problems with THAT box (stock) would take another 1000 words to describe. Suffice it to say that the 8100A/Audio Prism/MSI CP-803 (rebuilt) is as good or better then ANY current processor-and I'm talking loudness wise too!
Newer is not always better....especially new just for the sake of new.
I would be glad to continue this off list if anyone wants. My email is [email protected]
Over the past 25+ years I have modded close to 100 of these units (and 8000's as well). The main problem with them is the quality of the negative power supply and the general quality of the chips and caps used within them. Bob Orban is a master marketer; he designed his units to slowly degrade over time, so when you compare his newest box against the older one, it blows it away! HALF of this is not because his new box is that much better-instead the older unit has degraded to the point where it's half as good as it was when new. In addition, he used TLO opamps in these-which were great in 1975, but suck in 2007!
In an 8100, replace ANY light purple or orange electrolytic caps on ANY card-they have long dried up. Replace the bass DC coupling cap (it's tantalum) with a nonpolar. The VCA's in these units are fine-if you look at how they're used, they live within the feedback loop of a 5534 opamp-audio does not directly pass through them. By the way, they're used in the stereo generator too-and properly adjusted you can get upwards of 55 db separation midband with this unit. The VCA's are a stock RCA product.
The problem with bass grunge in most units is caused by one half of IC-310 on cards 3 and 4 sitting there oscillating. It screws up the power of the half that the bass goes through. I discovered this YEARS ago and reported it to Orban, who told me I was crazy until they looked at a card and found NONE of the 3 pins on the opamp were connected to anything. It's easy to configure this opamp as a voltage follower with it's non-inverting input connected to ground (If you don't know what I'm talking about, then you shouldn't be playing with these cards at the component level). By the way, to my knowlege Orban never came out with a bulletin about this, though they fixed it on all cards from that point (around 1986).
The "multi stage crossover with imbedded bass clipper" on cards 3 and 4 was put there so Bob could get a patent on it. It's simply two single pole filters cascaded with two clipping diodes in between them. By the way-the unit sounds MUCH better with these diodes OUT!
The back to back caps (with a film across them) on the filter cards (8 and 9) need to be replaced with a single 100 uf nonpolar.
I also put additional power supply filtering everywhere. The .1 disc caps on each card's power supply input are USELESS. Put a decent film there. Also, an official Orban mod is to replace the 25 uf caps here with 100 uf ones. I also drop an additional 6800 uf in each power supply rail-it stiffens things quite a bit.
I have rebuilt three of these units within the past few months (with their Audio Prisms as well) and the stations that put them in were all BLOWN AWAY by how great they sounded. They tried EVERYTHING against them and kept coming back to the analog processing time after time. I've had PD's do the same thing over the years. They all also use a MSI clipper-but the problems with THAT box (stock) would take another 1000 words to describe. Suffice it to say that the 8100A/Audio Prism/MSI CP-803 (rebuilt) is as good or better then ANY current processor-and I'm talking loudness wise too!
Newer is not always better....especially new just for the sake of new.
I would be glad to continue this off list if anyone wants. My email is [email protected]
Re: modifacation Optimod 8100A
As part of the recapping,i always replace c111,c11 psu o/p caps for 100u.
I prefer to leave the bass clipper diodes installed,when using the barefoot 8100.
Also when i have seen noise on one of the vca's,it has always been due to a faulty null or distortion trim pot,i have yet to see a faulty vca causing this(ca3280).
As you have probably seen an article which states to replace the vca if you see "popcorn noise" on the scope!
Where the opamp problem gets far worse is when the xt2 is involved,the whole audio path has a lot of opamps that colour the sound.
I have carefully looked at opamps here,and the best opamp to replace the 072 is the opa2134.
Of course,in conjunction with the xt2, the psu needs serious upgrades to supply the extra current,it just all depends how far you want to go.
As part of the recapping,i always replace c111,c11 psu o/p caps for 100u.
I prefer to leave the bass clipper diodes installed,when using the barefoot 8100.
Also when i have seen noise on one of the vca's,it has always been due to a faulty null or distortion trim pot,i have yet to see a faulty vca causing this(ca3280).
As you have probably seen an article which states to replace the vca if you see "popcorn noise" on the scope!
Where the opamp problem gets far worse is when the xt2 is involved,the whole audio path has a lot of opamps that colour the sound.
I have carefully looked at opamps here,and the best opamp to replace the 072 is the opa2134.
Of course,in conjunction with the xt2, the psu needs serious upgrades to supply the extra current,it just all depends how far you want to go.
Re: modifacation Optimod 8100A
Yes i have a load of tle2072's,the main difference i remember was slew rate and o/p drive increases.
As for noise and common mode problems i decided against them.
If i remember right they had a slew rate of 45v/us?
Did you see any burst oscillations using them on the standard cards(of course local decoupling becomes essential here)?
Have you seen this http://www.dself.dsl.pipex.com/ampins/webbop/opamp.htm
A very interesting website,even though it has not been updated for a long time!
Yes i have a load of tle2072's,the main difference i remember was slew rate and o/p drive increases.
As for noise and common mode problems i decided against them.
If i remember right they had a slew rate of 45v/us?
Did you see any burst oscillations using them on the standard cards(of course local decoupling becomes essential here)?
Have you seen this http://www.dself.dsl.pipex.com/ampins/webbop/opamp.htm
A very interesting website,even though it has not been updated for a long time!
Re: modifacation Optimod 8100A
IIRC Bob stated the 8100's were discontinued due to lack of replacement parts. I'm guessing this means cards? I'm sure you can still find some of the other parts at electronic stores.
R
IIRC Bob stated the 8100's were discontinued due to lack of replacement parts. I'm guessing this means cards? I'm sure you can still find some of the other parts at electronic stores.
R
Re: modifacation Optimod 8100A
I remember Bob saying that the analogue meters were very expensive to obtain,hence why they fitted led meters on all but the main "vu meter".
The pcb's would be easy to make,but certain components may be now hard to get.
Also the metalwork for the box itself may be expensive.
Lets be honest,the 8100a is built like a tank!
Talking about parts,does anyone know the make and model of the 8200's lcd?
Mine seems ok except for a slight darkening on the far left and right,half way up.
I remember Bob saying that the analogue meters were very expensive to obtain,hence why they fitted led meters on all but the main "vu meter".
The pcb's would be easy to make,but certain components may be now hard to get.
Also the metalwork for the box itself may be expensive.
Lets be honest,the 8100a is built like a tank!
Talking about parts,does anyone know the make and model of the 8200's lcd?
Mine seems ok except for a slight darkening on the far left and right,half way up.
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