IJR's 2254/33609!

[chrissugar]

I was looking to some of these diode limiter schematics, including the one posted by Wonderlandaudio and I'm tempted more to find a transformerless silicon variation, something that does the diode compression but has no real connection to the old Neve comps.
Maybe we can start a new thread and discuss the posibilities.

chrissugar

 

[clintrubber]

[quote author="chrissugar"]I was looking to some of these diode limiter schematics, including the one posted by Wonderlandaudio and I'm tempted more to find a transformerless silicon variation, something that does the diode compression but has no real connection to the old Neve comps.
Maybe we can start a new thread and discuss the posibilities.

chrissugar[/quote]
If any resemblance to the 33609 is not required as far as TX'n'sound is concerned I figure we could still get a quickstart by using the upcoming boards of Wonderlandaudio but add a little board that replaces by TXs by silicon. I expect the balancing could be made good enough.

What do you think ?

But let me add that I do want to try TXs; I don't want to run the risk that Wonderlandaudio doesn't want to provide boards for such blasphemous TX-less actions :wink:

Bye,

Peter

 

[chrissugar]

[quote author="clintrubber"]
But let me add that I do want to try TXs; I don't want to run the risk that Wonderlandaudio doesn't want to provide boards for such blasphemous TX-less actions :wink:
[/quote]

Don't worry Peter, no risk at all. :grin:

My idea, is not to replace the transformers in the 33609, but to start a new, clean silicon only project. New sidechain with opamps. No need for all that 33609 mess. :green: (blasphemy!)

chrissugar

 

[clintrubber]

[quote author="chrissugar"][quote author="clintrubber"]
But let me add that I do want to try TXs; I don't want to run the risk that Wonderlandaudio doesn't want to provide boards for such blasphemous TX-less actions :wink:
[/quote]

Don't worry Peter, no risk at all. :grin:

My idea, is not to replace the transformers in the 33609, but to start a new, clean silicon only project. New sidechain with opamps. No need for all that 33609 mess. :green: (blasphemy!)

chrissugar[/quote]
Ehh, oops, I see. :thumb:

It'd be interesting to hear your result, since I'm not sure what people like best of the 2254/33609/...: the very diode-action itself or the TX-treatment.

I actually liked that 33609-sidechain; lots of simple & easy parts (apart from the switches). Together with a signal-path with a dual CFP after the diode-bridge it all looked very interesting.

BTW, I arrived at the 33609 because I wanted to do something with some matched diodes (six on the same die: NOS CA3019). A Korg VCF was the other option.

Cheers,

Peter

 

[clintrubber]

[quote author="kubi"][quote author="clintrubber"]I recall that Rafa had plans to attack this design with OEPs. No idea about his progress.[/quote]

Most of the sound derives from the multiple transformers in the path. I'm not sure if you really want to replace the iron with OEPs or silicon.[/quote]

Hmm, we've both just been here:
http://www.groupdiy.com/index.php?topic=245514

I vaguely recall I read somewhere here that Belclere went on to become OEP in some way.
And the pics there look not unlike present day OEP-stuff.
But we shouldn't judge a TX only by its looks of course.

Bye,

Peter

 

[Igor]

This compressor deserves good iron. It is the sound.
One guy ordered from me two of these comp's and we used
choke+ungapped out trafo, line in's old round ones, and by the reason
it was impossible to find any original mic inputs, I just re-wound same line in (to use same iron).
Choke + ungapped trunny sounds killer (in good sence) for drums, and compared to original 2254, there's same character of sound and compression.
Original by unknown reason sounded very tiny bit more distorted on highs.
Choke+ungapped gave very "neevish" lows on drums/bass (we preferred this combination).

 

[mikeyB]

Having heard the UAD 33609, I want the real thing! Big up to Igor and all involved in this thread :thumb:
Having a hatred for interwiring, and being cheap(well - skint!) I'm going to have a crack at re-CADing the PCB - if thats ok with Igor and co.
I plan to incorporate the BA283 onto the same PCB and where possible, any of the controls. This will most likely end up a main PCB and Front panel PCB carrying the switches and pots. Would like to use Lorlins where possible. Are the switches bigger than 12 way replaceable with pots. Would the resulting scale/action be usable/unusable - I've not plotted out the resistance/rotation graph to see if it would be too "lumpy" or not :!:
Would also try and cad in for alternative transformers - anybody let me know about alternatives such as OEP, Ive seen the sowter alternatives.

Anymore input on this would be much appreciated.

Should imagine a there'll be group buys to come.

Igor - would you be willing to help on setup procedure
:?: :wink:

 

[mikeyB]

[quote author="kubi"]Any progress here?
Does anybody have a PCB layout without the component overlay as hosted by igor?[/quote]

Hello Kubi - I had a try of the Sprint-Layout 5.0 Demo software as recommended by sonicwarrior :thumb: :guinness:
and liked it. played it for a couple of hours and then took me less than an hour to trace over Igors green board. As soon as I buy the software i'll be straight onto it - all being well with no objections from anyone :grin:

 

[babyhead]

[quote author="mikeyB"]
Igor - would you be willing to help on setup procedure
:?: :wink:[/quote]

It's just nice seeing a post!

Igor does the best work.

:guinness:

 

[mikeyB]

[quote author="kubi"]Mikey, are you designing a layout for the original circuit or the "mixed-up-circuit" by IJR?
Anyway, I keep my fingers crossed for your project![/quote]

I like the sound (or should I say description) of IJR's hybrid. looking at the possibility of switching output sections - I need to study the ccts some more and see what can be done :razz:

 

[mikeyB]

Just been looking at the 33609 schem - has anybody got specs/info or an alternative for the output tran TF12009. Also trying to hunt down 1N4153 - Farnell list but they are out of stock - any available in europe, pref UK?? How many 1N4148 would be needed to get close enough match and how close do they have to match ie, Vf to within 1 or 2 mV??

 

[Tekay]

The 33609 manual partlist says "selected 1N4148 diode low VF" so I guess it doesn't matter if you use 1N4153 or 1N4148, it just takes more to match the 1N4148. They're only matched in pairs.
TF12009 is an 8dB step up transformormer, LO1173. If you use another outputstage and an outputtransformer with a different ratio the limithreshold will not track is it's contructed to be feeeded with a signal that is 8dB below the balanced outputlevel

 

[mikeyB]

Thanks Tekay - that helps to clear things a little. How "close" do the diodes have to match?
Kubi - I'm tempted to go with a "do all" PCB. If I'm not being too adventureous, I'll try and track in both signal paths, components - the sidechain is the same. Then on what ouptut you decide on determines the transformer. Anybody point me to the mechanical specs for transformers used in this project?

 

[matthias]

instead of the matched diodes ams neve used a zdx 1R and zdx 1F in their 33609 re-issue

 

[Tekay]

I match them down to 1mv.
ZDX1R / 1F sound like obsolete parts? If so, I wonder what AMS uses today as obsolete parts ain't RoHS compliant :?

 

[clintrubber]

[quote author="matthias"]instead of the matched diodes ams neve used a zdx 1R and zdx 1F in their 33609 re-issue[/quote]

How about (pin-incompatible) stuff like the CA3019 diode-array etc ?

I have a few NOS of that type (six diodes on a single die); when looking for an application for them I stumbled upon the 33609. Dunno if they're 'correct' w.r.t. V/I, but that could be tuned I expect.

 

[mikeyB]

Thanks Tekay - time to make a jig (to test diodes - other type of jig at the end - when I have built a 33609!!).
Clintrubber - CA3019 is obsolete so would rather use current products. 1N4153 out of stock so going the matched 4148 route. :grin:

 

[nrgrecording]

[quote author="mikeyB"]Clintrubber - CA3019 is obsolete[/quote]

What about the CA3046?

 

[clintrubber]

[quote author="mikeyB"]Clintrubber - CA3019 is obsolete so would rather use current products. 1N4153 out of stock so going the matched 4148 route. :grin:[/quote]

Hi,

Sure, I wouldn't advise other people using the CA3019 ! :thumb:

Bye,

Peter

 

[mikeyB]

Anybody got mechanical specs on the 10468 and 31267 transformers.
I'm looking at the PCB layout and mechanics and also collating and proof reading :? what we got so far :!:
Well actually, I've been doing this all day so it's time for :guinness: :guinness: :guinness: :guinness:

ps read earlier of igor doing a pure 33609 clone and the 31267 and 10468 are same as in his hybrid - is this correct as the 33609 circuit has the windings wired differently - parallel in some case :!: Can anybody verify this.
I would REALLY like to make a PCB that can be pure 33609 OR Igors Hybrid.

pps Whats the opamp on the BA640 :?:

:guinness: time - nighty-night