Official 33609 builder's tread. See 1st page for updates.

[kazper]

OA202 instead of 1n4153 is a good substitute here?

Or does anybody know a source for 1n4153? Didnt get them with the pcbs

http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/1N4153/?qs=sGAEpiMZZMtEwUVCuofpuIdIm5K%2fpoGrLpsAaw%252bSWv4%3d

 

[Biasrocks]

Still not sure where the offset came from, but the caps weren't shorted. Could have been chasing my tail for all I know.

I've got the beast put together with both channels functional, aside from a small wiring problem on the B channel comp threshold, which I'm sure is just a loose connection inside of one of those molex connectors. Did I mention I have a love/hate relationship with those damn molex connectors! Yes, they make life a bit easier for servicing, but those pins are a bit tricky to get 100% seated so they
don't pop out on re-insertion.

I still have a minor issue with not being able to get the limiter to track a 4db level, I'm actually getting around 6.4db on the output with the limiter fully engaged. I'm assuming it has something to do with the LO1166 having an extra 2db of level and the gain switch resistor choices. Hopefully Igor will chime in with a suggestion on the output gain resistor ladder for a +10db output transformer.

Tomorrow I'll hunt down that last little gremlin, tidy it up, seal it and start punching tracks through it.

A very cool project that I'm sure will see a ton of use.

It was by far the most challenging build so far.

Thanks for all the help and support guys!  8)

Mark

 

[tomcat]

OA202 instead of 1n4153 is a good substitute here?

Or does anybody know a source for 1n4153? Didnt get them with the pcbs

http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/1N4153/?qs=sGAEpiMZZMtEwUVCuofpuIdIm5K%2fpoGrLpsAaw%252bSWv4%3d

Oh, thanks a lot, sometimes i forget the good old mouser

 

[Biasrocks]

I'm having a heck of a time getting my hands on 1% 820R 1/4W resistors.

Newark in Canada doesn't seem to have them, and when I did find them I ordered SMT's by mistake! No workie.

Does anyone have any spare 820R's they could send my way?

Mark

 

[Biasrocks]

I found the best way to fasten the transformers is to use cable ties, but not too tightly, & then use some hot melt glue to stop the transformer slopping around.   I tend to use hot melt glue with all larger caps too.  I like that type of glue because it is pretty secure, but in the event of needing to change a component, its is also quite easy to remove.

Great tip, I'll try that.

Thanks Rob.

Mark

 

[Igor]

Curious if there was any consensus on the value of R10'
(6K8 or 24K) in the compressor release section,

24k for compressor; one manual shows 6k8, another 24k for limiter section....
I'd use both 24k.

I'm having a heck of a time getting my hands on 1% 820R 1/4W resistors.

825R will work fine

Did I mention I have a love/hate relationship with those damn molex connectors! Yes, they make life a bit easier for servicing, but those pins are a bit tricky to get 100% seated so they
don't pop out on re-insertion.

Yes, they a bit tricky, some rehearsals recommended
In any case, just bent them a bit, to fit in crimp base. For me, it takes same time
to make crimp assembly as solder wires to board. All this is just matter of patience.

I still have a minor issue with not being able to get the limiter to track a 4db level, I'm actually getting around 6.4db on the output with the limiter fully engaged. I'm assuming it has something to do with the LO1166 having an extra 2db of level and the gain switch resistor choices. Hopefully Igor will chime in with a suggestion on the output gain resistor ladder for a +10db output transformer.

Why not +4 db? BA340 not supposed to drive 50 Ohm.

It was by far the most challenging build so far.

Yes, 33609 is not easy project. Requires many patience.

Or does anybody know a source for 1n4153? Didnt get them with the pcbs

1N4153 have no sub, imho, but easy to get them on farnell/mouser.

Way to go! I like to see those late night posts with a good result.
I'll be putting mine back together as soon as the Elma's arrive and can help with measurements then.
I don't see how there would be voltage on the primary with the BC214s to blame. It only points to the obvious for me - that there was a short somehow across one of the capacitors.

There are small PCB's with holes which supposed to be down the trunny's to isolate them from main PCB.

I found the best way to fasten the transformers is to use cable ties, but not too tightly, & then use some hot melt glue to stop the transformer slopping around.  I tend to use hot melt glue with all larger caps too.  I like that type of glue because it is pretty secure, but in the event of needing to change a component, its is also quite easy to remove.

Don't use the glue. It can cause contamination later.

I'm not 100% sure what the cure was but I ended up pulling both transformers off the
board, replacing the two BC241's right after the JFET which seemed to have gotten rid
of the 4V offset to the interstage, I'm now down to around .11v of offset which seems
much more reasonable. Lastly it seems that there were cold solder joints around the
primary transformer, probably as a result of over tightening the zip ties. Next time I'll
be more careful to get them secure but not too secure.

Small boards with holes should be placed down the transformers.
We already had this discussion here.

 

[dmp]

I'm having a heck of a time getting my hands on 1% 820R 1/4W resistors.

What about:
271-820-rc (mouser)
if you can't order from Mouser for some reason I could add them when I do another order.

 

[Biasrocks]

Thanks for the generous offer.  8)

I've managed to source some from Ebay for a decent price, should be here in a few days.

Also, Igor the BA340 sounds great driving a LO1166 at 50 ohms.

I'll post some sounds samples when I get a chance.

Mark

 

[Biasrocks]

I still have a minor issue with not being able to get the limiter to track a 4db level, I'm actually getting around 6.4db on the output with the limiter fully engaged. I'm assuming it has something to do with the LO1166 having an extra 2db of level and the gain switch resistor choices. Hopefully Igor will chime in with a suggestion on the output gain resistor ladder for a +10db output transformer.

Why not +4 db? BA340 not supposed to drive 50 Ohm.

Thanks for the clarification Igor.

The BA340 will drive an LO1166 with out issue. The BA340/LO2567 combination is used in the 1081 channel amplifier.

From Geoff Tanner

"The burning question is... where did you get that circuit info from? A genuine Neve EX10340 diagram or some illegally posted redrawn diagram off the web. It sounds like the latter because there is no way on the planet that you'd get enough current through a 100K resistor to drive a 50 ohm primary 2567! Too silly for words!"

http://www.auroraaudio.net/dcforum/DCForumID1/218.html

"I believe the 1081 reissue came out before the 1073 (someone correct me if I'm wrong) and the LO2567 in the 1081 has identical windings to the LO1166... the difference being that the lamination's are stacked differently."

http://www.gearslutz.com/board/1865536-post6.html


My ears verify that it sounds just fine too.

Mark

 

[Biasrocks]

Hey guys, finally got her up and running fully and I'm very happy with the results.

Transformers I used in this build are

Input: Marinair 31267
Interstage: St.Ives 10468
Output: Ed Anderson LO1166 Output, configured for 50:600 +10db

I've not had time to explore all the possibilities but here are a few sound samples I came up with.

16bit, 44.1kHz .wav files

Drum bus, Kick and Snare pattern
Comp: 4:1, 100ms release
Limiter: Slow Attack, 50ms release

Before: http://sharktankpro.com/GDIY/33609/DrumsSample-33609-Before.wav
After:   http://sharktankpro.com/GDIY/33609/DrumsSample-33609-After.wav

Drum bus
Comp: 3:1, 400ms release
Limiter: Slow Attack, 100ms release

Before: http://sharktankpro.com/GDIY/33609/DrumsSample2-33609-Before.wav
After:   http://sharktankpro.com/GDIY/33609/DrumsSample2-33609-After.wav

Mixbus, 3:1, A1 release

Before: http://sharktankpro.com/GDIY/33609/MixSample33609-Before.wav
After:   http://sharktankpro.com/GDIY/33609/MixSample33609-After.wav

Mastered: http://sharktankpro.com/GDIY/33609/MixSample33609-Mastered.wav

Really great sounding limiter and a nice addition to the arsenal.

Thanks again for all the help and guidance!!

8)

Mark

 

[tommypiper]

You have noise in the processed track.  I only listened to the first pair of tracks, and there is signficantly more noise in the compressed version.  I also heard noise in the original, so maybe if you have a lot of makeup gain that would explain it being noiser in the processed version.  Or is the compressor adding the noise?

 

[Biasrocks]

Sorry, not hearing it.

Of course, "noise" could be just about anything.

Keep in mind, there's 12 odd microphones with various levels of processing going into
what your hearing. Including some one giving direction to the drummer which is perhaps
what you're hearing.

Mark

 

[tommypiper]

It's the noise floor, hiss.  Seems too high. I'll repeat:  It's higher in the compressed file.  Is that coming from the 33609 or are you just adding a lot of make up gain which raises the original noise floor?

 

[Biasrocks]

It's the noise floor, hiss.  Seems too high. I'll repeat:  It's higher in the compressed file.  Is that coming from the 33609 or are you just adding a lot of make up gain which raises the original noise floor?

Sorry, not hearing the hiss, but I come from an analog world.

It could be the dithering that was added to the stereo samples to get them down to 16/44.1
from 24/96 that you're hearing. You said you heard it in the original clip, so the comp/limiting
with added make-up gain; there was easily 10db of gain reduction happening on the peaks, would
bring up the noise along with everything else. As far as the 33609 it's dead silent, I could not detect
any noise when I plugged my headphones into the back and cranked the gain.

Edit: Okay, I went back and listened, and yes the noise floor is present between the cycling of
the pattern. I had to CRANK my monitors to deafening levels hear it at all. Considering that
there's 12 microphones, mic-pres, eq's and various compressors feeding that drum sound. There's
also a tape sim plugin inserted on the drum bus before the compressor which adds a small amount
of "analog dither".

The noise is not coming from the limiter.

Mark

 

[mg73]

The lowest voltage I manage to get over R44 10R is 477mV??
I didn´t build this unit just trying to help a friend with the last
steps  it looks like all parts are  where
they should be.

NTE326(ordinary black) and NTE324(metal can) instead of 441 and 461
on the DOA

Any hints where to start?

 

[dmp]

Looks like the substitution should be NTE323 (PNP) & NTE324 (NPN). Check the datasheets, yes? The NTE326 doesn't look like the right part to go there at all.
A higher voltage drop indicates that the DOA is drawing more current. It is biased higher. 

 

[Biasrocks]

My xref shows

BC441 = BCX 40, 2N4238, 2SC2214
BC461 = BCX 60, 2N4236

The 2N423* parts are likely candidates.

Mark

 

[mg73]

Yep that what it.
Changed them to 2n4037 and now it reads fine,

Regarding meters this came with  a Sifam AL19 Vu scale
do they work? because I now that a sifam peak meter is used on the originals.

 

[dmp]

Huh?
The BC441/BC461 is a complementary pair used to drive the output, like push-pull. They need to be npn / pnp to work correctly, so changing

them to 2n4037

is not going to work.

 

[Wonderlandaudio]

Huh?
The BC441/BC461 is a complementary pair used to drive the output, like push-pull. They need to be npn / pnp to work correctly, so changing

them to 2n4037

is not going to work.

Best substitutes are 2n3053 / 2n2905, better the A versions.