Yamaha M1516/PM2000 Discrete op-amps?

I'm picking one of these up today & wondered if there's any components of value that could be used for some good DIY pre's or whatever?

It's supposed to have the NE-80200 discrete op-amps on every channel for the mic pre's + a few output tranny's on the master section.

Some call it the little brother of the PM2000.

I took some pics of mine for you.


Here's the channel card...

http://img86.imageshack.us/img86/4530/m1516card2ca.jpg

Some more transformers on the inside...

http://img111.imageshack.us/img111/5251/m1516trafos7yb.jpg

Tamura transformer count...

GA80980-Mic input transformers 300:2.7k: 16
GA81720-Output transformers: 13
GA81710: Smaller input transformers for foldback, echo, talkback, etc: 13

...plus 16 80200 discrete opamps.

I've always liked this desk. Now I know why after opening it up. The input trafos look to be similar quality to the PM-1000 trafos. The board looks to be almost entirely discrete except for 2 6552s in the eq section--which coincidentally is the only part of the console I don't particularly like the sound of. If you don't have to pay for shipping these things are a steal for what they go for on ebay.

-Ben

I opened the board up yesteday & it is loaded :shock:

Do you think those OT's are the same as in the PM2000? What do you think they'd be good for?

I racked 2 PM1000's & they are absolutly killer, headroom out the ass.

I also have a single PM2000 strip & thought about doing a single rack ... I have the FULL schematic (about 4 feet x 4 feet :shock: ) but don't know if it's worth it or even were to start - like with the power supply & where in the circuit to pull the final output :?:

I'd like to use the I/O tranny's & the discrete 80200's to make an API like mike pre... is this possible?

I'd like to use the I/O tranny's & the discrete 80200's to make an API like mike pre... is this possible?[/quote]

Yes, you can...
You could go with a different input trans, or use the one thats in the console.
The output transformers have a nice warm sound.
Same pin out as the API 2520.

[quote author="Kevin"]I'd like to use the I/O tranny's & the discrete 80200's to make an API like mike pre... is this possible?[/quote]

[quote author="Mike Keith"]Yes, you can...
You could go with a different input trans, or use the one thats in the console.
The output transformers have a nice warm sound.
Same pin out as the API 2520.[/quote]

Hey Thanks,
I think the OT's I have (GA81720) are 600:600

When you say different input tranny are you reffering to a higher ratio for more up front gain or just something better?

Can you or anyone recommend a specific pre that would work with these components? & possibly post a link.

The API (312 I think it is) looks very simple... I was also checking out the JLM stuff - Dual 99v, etc...

I think I'm sitting on a nice stack of parts here & would love to put them to good use. I will share my build info & findings because these old Yamaha board are loaded with good parts for DIY & can be had fairly cheap :green: I may also sell some of the extra discretes & trannys.

Kevin

Yes, you can build a nice 312-type design with the Yamaha parts. I've done it, and they sound very good. The problem is that the overall gain of the circuit is much less than a 312. The Yamaha input transformer is a 1:3 (9dB gain) instead of the 312's 1:10 (about 20dB -- an 11dB difference) and the output transformer is a 1:1, with no gain, as opposed to the 6dB step-up of the 312's 1:2 output wiring.

That's about -17dB difference for the total gain of a 312 made with the Yamaha components. So there's not enough gain for quiet things, particularly when using ribbon or other low-output mics. It's a nice-sounding circuit, and certainly worth building considering the cost of the parts, but I really miss the extra level that it can't provide.

The PM2000 mic preamp design actually uses a second opamp, a toshiba IC package (I forget which model). the design is rather complicated (like a 5 or 6-pole gain switch), but I've considered building a variation of a 312 that basically adds a BB OPA604 opamp, after the Yamaha, with a fixed gain to provide the additional level that is missing from the circuit as a result of the lower ratio transformers. I really like the OPA604 sonically, and it can run on +/-24v rails just like the Yamaha opamp does, and it can drive the 1:1 transformer too, so I'm confident it'd be a good match.

I haven't tried this yet, however, and it'll be another few months before I get around to it, I'm sure (I've got Marinair reissues and Neve on the brain at the moment :grin

JC

I have some UTC 150/500:60k input tranny's...

Could I use them?

The primary seems ok but the secondary... :? ???

Might have a Zobel nightmare?

Why not use an API 2503? Approx. 9db of gain and sound very good...
You can get more gain out of the OP amp, I have of few of those I could check for noise..

I have no problem with that except I'm trying to build some pre's out of what I already have. Maybe I should be looking at using 2 gain stages (NE-80200) with these tranny's I have?


What is an API 2503... a tranny?

Yup, an output transformer... used for API 325, 312, 512, etc.

[quote author="khstudio"]Maybe I should be looking at using 2 gain stages (NE-80200) with these tranny's I have?[/quote]

Exactly.

[quote author="mattmoogus"][quote author="khstudio"]Maybe I should be looking at using 2 gain stages (NE-80200) with these tranny's I have?[/quote]

Exactly.[/quote]

What's the story with the JLM stuff... will these work in the dual 99v or baby animal or what?
I guess the later isn't ready for sale yet?


Thanks for helping :thumb:

ANY other opinions on what I can make out of this stuff would be GREAT.
I'd like to keep it simple, cost effective & have some pre's that kick ass .:green:

I'll also say that I'm pretty good but not the best at this stuff... especially after my friend died... he had ALL the answers.

I'd be willing to sell or trade some of the input & output tranny's & a few of the NE-80200 discretes, if I only new what they're worth.

I could use:
boards, parts, power supplies or trannys that I could use for my mic pre adventure :wink:

[quote author="khstudio"]I have some UTC 150/500:60k input tranny's...

Could I use them? The primary seems ok but the secondary... :? ???
Might have a Zobel nightmare?[/quote]

WELL TRY IT!!!! :roll:

Don't expect to get all the answers served on a platter. The fun part is experimenting and learning.

You have parts - start building - NOW! :grin: :grin:

[quote author="cuelist"][quote author="khstudio"]I have some UTC 150/500:60k input tranny's...

Could I use them? The primary seems ok but the secondary... :? ???
Might have a Zobel nightmare?[/quote]

WELL TRY IT!!!! :roll:

Don't expect to get all the answers served on a platter. The fun part is experimenting and learning.

You have parts - start building - NOW! :grin: :grin:[/quote]


I'll quote myself

I'll also say that I'm pretty good but not the best at this stuff...

Click to expand...

Look, I've seen some people on these forums really get out of hand with beating people up asking a lot of questions about super basic shit, & in my opinion, transformers aren't basic shit, &/or these discrete & how to implement them.

Also, I'm gathering as much info as I can before I start because I don't have any power supplies & I'm really not sure if I'm going 2-ch or 8-ch or going to use the JLM boards or just etch my own... maybe an API, but after what I've learned in this thread, my gains might be too low...so right there is my point - I only have a few of the UTC's so an 8 channel, as oppossed to a 2ch, is out of the question, cause if I go 8ch I want them to match. + it would go over my budget$$$.

I'm learning man, bear with me :wink:

I also don't have tons of spare time so I like to see a project in my head or on paper from start to finish, then I can dive in with confidence.

Kevin

rascalseven,

About the API 312 with Yamaha Parts:

I have some 48 volt center tapped power tranny's I was thinking about using & wondered what voltage you used for yours when you tried it?

Since the NE-80200's can handle 24v instead of the API's 18-20v... I was thinking the extra voltage might help the gain loss a little.

Would this be ok or is there something better or easier?
http://www.forsselltech.com/gerbers/MikePrePS1.PDF


Thank again,
Kevin - KHStudio

24 volts will likely increase headroom, not gain. An IC after the Yamaha would take care of the extra gain needed. Just make sure the one you use can drive the output transformer properly (a 600:600).

Yes, that PSU will work fine.

JC

I'm gettign ready to place an order with JLM for some power supplies... they look killer :green:

My heads spinning with all these projects. I'd REALLY like to know if the NE-80200's will work in the Dual 99v boards, as another option.
Since I have several discretes I'd like to use 2 stages of those instead of an IC... I've got enough stuff with IC's.

As soon as I get a power supply I've got a PM2000 ch strip to try out also. I'll definitly post the results of that + it will give a idea of how these Yamaha op-amps sound. I think the EQ section has a bypass switch but the channel still doesn't look totaly discrete... oh well.

Is there ANY info available on the Tamura Output Tranny's?
The output trannys look pretty PHAT... I wonder if their gaped, also, there's 3 taps per side but Yamaha only uses the outers on both sides, without touching the middle... what the center pin for?


Kevin

Here's a thread at Klett's old place that might help.

HERE

Yamaha discrete op-amps:
NE-80200's & a few 80100's

BTW, These 2 op-amps are NOT the same under the hood... I had a bad 80100 & opened it up (you can see thru the bottom, filler is clear) & the 80100 has a few different components than the 80200. For 1, it looks like it uses 2 regulators next to the 4 pin side.

I started a new topic about using these part for a pre if anyone's is interested or can help :wink: :
http://www.groupdiy.com/index.php?topic=174335#174335