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What's the difference between Trident 80 & 80B ?
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sage691
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6th June 2006
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What's the difference between Trident 80 & 80B ?

Does anybody know what all makes them different from each other ? Are the differences in sound and flexibility really all that great ?

The 80B seems to be the most famous one from all my net research.

Just cheking to see if any knowledgeable person out there can expound on this subject.
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I've been doing a lot of research lately. This is all I've found so far.

The 80 was the first one built in 1979. Then came the 80B. In the 80B, there are some slight differences in the master section. There were two different circuit board cards used in the 80 series. There was a revision made somewhere in the early 1980s that resulted in another circuit board being implimented. On the newer CBs, the eq was apparently changed for the better. My particular 80B has the older input modules in it, so the eq does some fairly intresting things. There are also some transistors on the older input modules that aren't made anymore. If they go bad, you have to replace them with some kind of cap/resistor combo. I have no idea on the specifics, but that's what I heard from my tech.

Hope this helps you out.

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I bought an 80B brand new from Trident in 1983. At the time, I was informed that there were only four differences between the 80 and the 80B. Both used the same input module, so there was no difference there at all. Modules were $1200 each at the time.

1) The 80 used a patchbay with jumpers on the back that would allow you to normal/halfnormal a patch point by moving the jumper. What seemed like a good idea at the time turned out to be not so good. It was problematic. Anyone who has used a patchbay knows that the last thing you need is another contact to corrode in the signal path. The 80B patchbay was hardwired.

2) The 80 used an all steel frame. The 80B used an aluminum frame.

3) The 80B used Alps faders instead of Penny & Giles.

4) Since all of the above were cost-cutting measures, the price was substantially less for the 80B.


The biggest difference I'm aware of on the 80C was the addition of EQ in the monitor section. Other than that, I'm not aware of any changes.

I have worked on all three and have never noticed any sonic differences between an 80, 80B or 80C.
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Great information, Lynn. Thanks. My series 80 was built in 1982.

The only difference I noticed when I was looking at a lot of them before I bought mine, was that 80B's tend to have a smaller number of inputs. This isn't true 100% of the time, but most of the 80B's I saw were 24X24. And most of the 80's I saw, like mine, were 40X24 or 32X24.
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I think the most popular config. was the 32 x 24, though many had it shortloaded. Mine was a 32 x 24 with 28 input modules. I did see several with only 24. And most either had the switch installed from the factory or aftermarket so that the monitor section would dump into the 2 mix master. That way you had 24 more line ins for reverb returns, synth ins, whatever. Back before we started mixing with automation, we'd used the short faders as additional inputs for BGVs and the like. It was the cheapest, best option for a 56 input console. Mine was $36,000 new delivered from England.

The 80s were closer to $60K. That's the main reason that the 80B became so popular. In the mid 80s, early 90s it seemed like all the big studios in LA had Neves in the main room and 80Bs in the B studio. It was respectable and not a huge investment.
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80 and 80b

Quote:
Originally Posted by phelbin
Great information, Lynn. Thanks. My series 80 was built in 1982.

The only difference I noticed when I was looking at a lot of them before I bought mine, was that 80B's tend to have a smaller number of inputs. This isn't true 100% of the time, but most of the 80B's I saw were 24X24. And most of the 80's I saw, like mine, were 40X24 or 32X24.
earliest "80Bs" were as Lynn described them. Later 80Bs had eq on the monitor section and 30 channels rather than 32. So far I haven't seen an 24 channel desks.


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I bought an original Series 80. The 80 could be had in up to a 40 input frame size, which I had. AFAIK, only 2 with 40 imput frames made it to the US. Mine and one Fredi Piro had at Mama Jo's in Hollywood.

And yes, the patchbay was problematic. It was comprised of PCBs that slid into edge connectors in the frame. Lots of cleaning to keep it right, along with a healthy smack every now and then. FWIW, I ended up modifying the heck out of my Series 80. The definite weak link in the chain was the summing buss. No headroom at all, as shipped.
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Series 80

Quote:
Originally Posted by BrianT
I bought an original Series 80. The 80 could be had in up to a 40 input frame size, which I had. AFAIK, only 2 with 40 imput frames made it to the US. Mine and one Fredi Piro had at Mama Jo's in Hollywood.

And yes, the patchbay was problematic. It was comprised of PCBs that slid into edge connectors in the frame. Lots of cleaning to keep it right, along with a healthy smack every now and then. FWIW, I ended up modifying the heck out of my Series 80. The definite weak link in the chain was the summing buss. No headroom at all, as shipped.
I agree with Brian regarding the summing buss. I bought some 325 cards and plan to try an API summing amp alternative or possibly a purple audio summing amp when I have some time to screw around with it.

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Yeah, there really is some science to a proper analog summing amp. Man, it's been a long time..............

I do remember changing the value of the isolation resisitors on the individual channels (IIRC they are attached to the main motherboard and not the individual input PCBs) to acheive better crosstalk figures. Then I heavily modified the summing amp itself, going through several iterations before I got happy. Can't remember much about that part now.

I do know this though. When tracking, if you will patch the channel input Insert Send Out directly to the multitrack, you will open the sound up quite a bit. The back end of the input channel has some unflattering circuitry in it, including some 100% negative feedback unity gain buffer amps. Those generally suck, sonically. And the Group bussing is no better sounding than the Stereo buss.

By feeding the multitrack directly from the channel Insert Send, you bypass everything unstellar about the console, but keep the goodness of the mic pre and EQ. Try it. I think you'll get a big grin on your face.
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OK, so you guys are saying that the stereo summing bus on the straight 80 is NOT as good as the one on the 80 B ?

To me, this is the most important part of the console as I will be using it mostly for final 2 track mixdown.

Which one has the biggest sounding, widest dynamic range stereo summing bus ?

Also, sounds like the 80 series though it was more expensive, will likely be the one to require more maintenance ?


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Quote:
Originally Posted by BrianT
AFAIK, only 2 with 40 imput frames made it to the US. Mine and one Fredi Piro had at Mama Jo's in Hollywood.
Mine is a 40 input frame series 80. I bought it about two years ago from a studio in Burbank.



Quote:
Originally Posted by sage691
OK, so you guys are saying that the stereo summing bus on the straight 80 is NOT as good as the one on the 80 B ?

To me, this is the most important part of the console as I will be using it mostly for final 2 track mixdown.

Also, sounds like the 80 series though it was more expensive, will likely be the one to require more maintenance ?
I like the sound of mine on the 2 bus. It's possible that it was modified before I bought it, but I'm definitely happy with it.

And mine hasn't had maintenance issues at all...until recently. One of my NS10's jumped off its stand and slammed down on the return section, which messed up the power supply and one return module. But any console would have trouble after something like that! Brian Roth is going to fix my PSU and module and I'll be up and going again.

So since I can't mix through my console for another week or two I tried to mix a song ITB since so many guys around here would have you believe that it's just as good. I couldn't get it to sound anywhere near as wide and clean as I can with my console. I hope he finishes quickly!
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Quote:
Originally Posted by Lynn Fuston
The 80B patchbay was hardwired.
Really? I thought this was a mod that someone did to my console.

Quote:
Originally Posted by Lynn Fuston
The 80B used Alps faders instead of Penny & Giles.
80B used Audiofad faders which are supposedly some of the best faders money can no longer buy. They started using Alps in the 65,70,75 and 24 series. P&Gs were used on the short monitor faders.

Quote:
Originally Posted by Lynn Fuston
The biggest difference I'm aware of on the 80C was the addition of EQ in the monitor section.
Now, I've gotten mixed info on this. Some said that all 80Bs had eq on the monitors. Some have said that it was an option. This makes the most sense to me, considering that mine is a "B" and it has no eq on the monitors.

The reason why some 80Bs are 30 channels is because they had to rob two channels to make room for two extra modules in the monitor section. The non-eq consoles had 6 monitor modules with four channels a piece. The ones with eq had 8 monitor modules with only three channels a piece.
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Quote:
Originally Posted by phelbin
Mine is a 40 input frame series 80. I bought it about two years ago from a studio in Burbank.





I like the sound of mine on the 2 bus. It's possible that it was modified before I bought it, but I'm definitely happy with it.

And mine hasn't had maintenance issues at all...until recently. One of my NS10's jumped off its stand and slammed down on the return section, which messed up the power supply and one return module. But any console would have trouble after something like that! Brian Roth is going to fix my PSU and module and I'll be up and going again.

So since I can't mix through my console for another week or two I tried to mix a song ITB since so many guys around here would have you believe that it's just as good. I couldn't get it to sound anywhere near as wide and clean as I can with my console. I hope he finishes quickly!

I'll bet if you ask Brian, he'll tell you that console started off at Mama Jo's. If that's true (and it almost has to be), the console is nowhere near stock. You got a good one.

OTOH, if it's somehow my old console (which I haven't seen in 20 years or so), I did an Insert Bypass mod where I stole the Pre/Post switch from one of the Aux sends (forget which one now) and turned it into Insert Bypass. I'll bet that may not have even been found by a subsequent owner. Lots of mods on a number of those Series 80(B) consoles. The Master of those mods was Bud Wyatt, but I had a trick or two of my own as well.
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80 and 80b

Quote:
Originally Posted by absrec
Really? I thought this was a mod that someone did to my console.


80B used Audiofad faders which are supposedly some of the best faders money can no longer buy. They started using Alps in the 65,70,75 and 24 series. P&Gs were used on the short monitor faders.


Now, I've gotten mixed info on this. Some said that all 80Bs had eq on the monitors. Some have said that it was an option. This makes the most sense to me, considering that mine is a "B" and it has no eq on the monitors.

The reason why some 80Bs are 30 channels is because they had to rob two channels to make room for two extra modules in the monitor section. The non-eq consoles had 6 monitor modules with four channels a piece. The ones with eq had 8 monitor modules with only three channels a piece.


This is my understanding (mostly from owning a Series 80 desk and having worked on both Series 80s and early Series 80Bs) - the patch bays in the Series 80 desks have removable cards lined up like shirts in a closet. The patch bays in the Series 80B desks are hardwired. The master sections on the Series 80 desks and the earliest Series 80B desks are interchangeable. While eq may have been an option
on 80Bs at the outset, it became standard at some point. Brian - does this jive with your experience.

If Dave Michaels or Kris Jackson were here they could fill in the holes.

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Lynn outlined the real differences... however a subsequent release of the 80B was 30 inputs and had EQ on the monitor section. The 80C was 32 inputs and had the capability of an "A" or "B" input on the 24 monitor inputs which would actually allow you to stack 48 inputs as long as the same level and EQ could apply to both the "A" and "B" inputs.
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Series-65

Hi!

What about the Trident Series-65 ? Do you guys have any information about that ?
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Quote:
Originally Posted by Haam
Hi!

What about the Trident Series-65 ? Do you guys have any information about that ?
The studio next door has a Series 65. Basically, when you look at the schematic and then look at the 65, you notice that the flow is similar to the 80 series. Except, there are no transformers. It seems like they were trying to build a console to appeal to the project studio market of that day. The 65 has an unmistakable tone, though. One which I really enjoy listening to if it's in the right hands.
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Quote:
Originally Posted by BrianT
I'll bet if you ask Brian, he'll tell you that console started off at Mama Jo's. If that's true (and it almost has to be), the console is nowhere near stock. You got a good one.

OTOH, if it's somehow my old console (which I haven't seen in 20 years or so), I did an Insert Bypass mod where I stole the Pre/Post switch from one of the Aux sends (forget which one now) and turned it into Insert Bypass. I'll bet that may not have even been found by a subsequent owner. Lots of mods on a number of those Series 80(B) consoles. The Master of those mods was Bud Wyatt, but I had a trick or two of my own as well.
I bought mine from a guy named Jamie Sutton. He's more of a console dealer, but was selling the house console from a small studio in Burbank he bought a while ago that is now his shop/office.

What would be the purpose of the insert bypass mod? And how would I figure out if mine has it...and if this was, in fact, your console?
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weren't there also 80B trafoloaded and hybrid and later ic ballanced??
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Quote:
Originally Posted by phelbin
I bought mine from a guy named Jamie Sutton. He's more of a console dealer, but was selling the house console from a small studio in Burbank he bought a while ago that is now his shop/office.

What would be the purpose of the insert bypass mod? And how would I figure out if mine has it...and if this was, in fact, your console?
Mama Jo's was in North Hollywood/Burbank, so that sounds like the one. No way there was more than one 40 frame that close. I've worked on that console.

You have a VERY nice sounding original Series 80, and it is nowhere near stock. Tasty mods were done to that desk. Pop out a channel strip and see if the opamps are LF351 instead of the (stock)TL071 or (some people's)NE5534. The LF351 was the coolest sounding in most of our opinions.

As far as the Insert Bypass. There is additional buffering curcuitry associated with the Insert Return that I don't like. It's a unity gain 100% negative feedback opamp design buffer and it's slew rate sucks, among other things. On the Series 80, that insert loop is a permanent part of the signal path, including the round trip through the patchbay, which includes a number of edge connector/PCB interfaces. It's needless if you're not using a piece of gear on the Insert.

So I used one of the Pre/Post switches for an Aux Send that I always wanted to be post anyway, and I used that switch to toggle between the Insert Return vs directly connecting the Insert Send to the back end of the channel. That allowed me to bypass the extra Insert circuitry whenever I didn't actually need to use the Insert on the channel.

Again, the way to really make that thing rock is to come straight out of the Insert Sends to the multitrack when tracking. More open and punchy going to tape than coming out the Multitrack busses. Whatl you get extra for coming out the Multitrack busses is some gain control you really shouldn't need anyway, plus a bunch of extra opamps and a not-so-hot summing amp.

Only real maintenance issue is the patchbay cards. Keep them clean and well seated.
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Quote:
Originally Posted by absrec
Really? I thought this was a mod that someone did to my console.

80B used Audiofad faders which are supposedly some of the best faders money can no longer buy. They started using Alps in the 65,70,75 and 24 series. P&Gs were used on the short monitor faders.

Now, I've gotten mixed info on this. Some said that all 80Bs had eq on the monitors. Some have said that it was an option. This makes the most sense to me, considering that mine is a "B" and it has no eq on the monitors.

The reason why some 80Bs are 30 channels is because they had to rob two channels to make room for two extra modules in the monitor section. The non-eq consoles had 6 monitor modules with four channels a piece. The ones with eq had 8 monitor modules with only three channels a piece.
I never pulled mine to look but was told by the Trident dealer (Wally Wilson was his name) that the faders were Alps. Mine was built in 1983, so that may figure into it.

The original stock 80B from Trident used the faders as the bus out masters and the little red knobs in the monitor section as the volume control for tape returns, i.e. the actual monitor mix. But so many people were using the monitor side for additional inputs in mixdown that reversing those from the factory was quite common, so the faders were now the monitor mix and the little red knobs were the bus out masters. I ordered mine that way.

Anyone who tells you that all 80Bs had EQ on the monitor side is just wrong. Mine didn't. Most of the ones I've worked on didn't. The monitor section was four up, six wide.
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My series 80 has the small faders as return volume and the red knobs are the bus outputs. Would that be a mod on mine too?


Quote:
Originally Posted by BrianT
You have a VERY nice sounding original Series 80, and it is nowhere near stock. Tasty mods were done to that desk. Pop out a channel strip and see if the opamps are LF351 instead of the (stock)TL071 or (some people's)NE5534. The LF351 was the coolest sounding in most of our opinions.
I'll check them them next time I'm in. But if they still are stock, how difficult would that be to change. I'm not very experienced with electronics. Would that be better left to someone who knows what they're doing?


Quote:
Originally Posted by BrianT
So I used one of the Pre/Post switches for an Aux Send that I always wanted to be post anyway, and I used that switch to toggle between the Insert Return vs directly connecting the Insert Send to the back end of the channel. That allowed me to bypass the extra Insert circuitry whenever I didn't actually need to use the Insert on the channel.
Which pre/post switch would you have used? Are we are talking about the green pre/post switches next to the aux knobs on each channel?

And so using that mod would allow the signal to bypass the insert/return circuitry to go directly to the output and then the 2bus when mixing? Because when tracking individual channels to tape I'd just patch from the insert to the tape machine. Is that right? Again, I'm new to consoles and circuitry in general. So I'm just trying to make sure I have this all right. And I'm very excited to know this was all done to my console.



Quote:
Originally Posted by BrianT
Again, the way to really make that thing rock is to come straight out of the Insert Sends to the multitrack when tracking.
I've always patched from the channel direct output to the tape machine, which I've found sounds better than the bus outputs. But I'm going to try this as soon as I can.
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Quote:
Originally Posted by phelbin
My series 80 has the small faders as return volume and the red knobs are the bus outputs. Would that be a mod on mine too?
Yes, but not necessarily modded after delivery. Trident were very willing to change things on the console (i.e. switch caps, knob colors, routing) for buyers. It probably came that way from the factory.
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I've owned (and still own 1) 2-80b's and an 80c. 1 80B had no eq on the monitor (4 up and 6 wide) and was pretty straight forward and unmodded. My other 80B had 30 inputs and a little eq on the "jukebox" or right hand side of the board ( 3 up 8 wide) My 80C had full EQ(just like the inputs) on monitor. The word on the street is that Trident actually fixed the mid range EQ funky stuff on the monitor section ( never fixed the input modules)
All of the input modules from any series can be switched between boards. The later 80b's and 80c's had a 5534(or is it a 5532?) put in the output stage and went away from the "semi-discrete output driver circuit. Many people feel this is why earlier 80b's are the best sounding of all of the Tridents and hence its popularity.
For all intents and purposes the 80c is by far the most useful in a modern recording setup, but they are rarer. The way Trident kept using the same input boards layout, you can actually swap back out the 5532 and repopulate the input board with a tl072 and the discreet components for the "early 80b" discrete output.
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Quote:
Originally Posted by phelbin
My series 80 has the small faders as return volume and the red knobs are the bus outputs. Would that be a mod on mine too?
My 80B has short faders for the returns. In place of those little little red knobs you speak of are trim pots that adjust the level of all 24 bus outputs. I mean there is no knob to accidentally bump with your hand. You have to get a screw driver down in there.

Mine's got a fair amount of mods that were probably from the factory. It's got isolation transformers on all 24 busses and PPM meters.

Quote:
Originally Posted by Lynn Fuston
I never pulled mine to look but was told by the Trident dealer (Wally Wilson was his name) that the faders were Alps.
I don't think they were alps. Trident used Audiofad faders on the 80 and 80B and possibly the 80C, although I don't know that for sure. Audiofads are great faders. They don't make them anymore. Apparently the taper is some odd size too, like 110mm. If I ever need to replace mine, I'll need to have the plates machined to accomodate a "standard" sized fader.
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Quote:
Originally Posted by studio1117
For all intents and purposes the 80c is by far the most useful in a modern recording setup, but they are rarer. The way Trident kept using the same input boards layout, you can actually swap back out the 5532 and repopulate the input board with a tl072 and the discreet components for the "early 80b" discrete output.
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Don't do that! The 5532 and tl072 are dual package opamps, they will blow. Use the single package opamps, the tl071/lf351/5534.

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Of course Jim is right, it's a 5534 in there.
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Quote:
Originally Posted by BrianT
Pop out a channel strip and see if the opamps are LF351 instead of the (stock)TL071 or (some people's)NE5534. The LF351 was the coolest sounding in most of our opinions.
My input modules have 16 TL071's and 1 NE5534 on the mix amp. And there are 40 TL071's on the return modules. I'd really like to get the LF351's. What kind of difference are we talking about? Do I put them on all the opamps or just certain ones? And where would I even get ahold of them?
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Well Jim seems to be the guru on this in many peoples opinion so he can probably answer better than I can, but usually, people just change the Mic pre op-amp in my experience. I always left my boards stock. I figure John and Malcolm knew better than I did how the circuit should be run.
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Here's how I handle the mic pre cards. These are a dual opamp inverter design that causes a secondary transformer impedance shift with gain variation.
At low gains the transformer sees 120k ohms, at high gains it sees 22k ohms. This causes damping at low gains and overshoot at high gains, constantly changing with the gain setting.

To fix this, set the first stage into a non inverting configuration.

Cut the trace from IC 13 pin 3 to ground. Cut the trace from R101 (22k) that goes to the transformer yellow wire. Connect the yellow transformer wire to pin 3, connect R101 to ground. Add a 100k resistor from pin 3 of IC 13 to ground. Reverse the red and black wires on the XLR connector to retain phase. Add a 10 pf mono ceramic NPO cap into that empty feedback spot next to the second opamp, IC 12. Change C38, the 22 uf tantalum cap to a Panasonic FM 220 uf 25 v cap. Use another one for C36. Add a pair of .1 uf mono ceramic caps from pin's 4 and 7 to ground on one of the opamps for power supply decoupling.
For air, add a Wima MKP-2 .01 uf 630v caps across C36 and C38.

Now you can play with opamps. Fet opamps are the rule here as bipolar input opamps with their high bias currents will cause scratch across the gain pot when turned. I like the OP134, the OP627, OP-42, and AD825 in this location.

For even better sonics, replace the transformer with a Jensen JT-115KE and change the 100k resistor from pin 3 to ground with a 150k ohm resistor.

BTW, similar work can be done to the rest of the module, although this much re-work isn't necessary. This was done to fix the Oram/Toft mic pre "mistakes".

Jim Williams
Audio Upgrades
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