Feeler: ez760 - Compressor/Limiter/Expander/Gate

[tonycamp]

Hi Steve,
  I am about to embark on a pair of these after ordering next week. I think you should pm Colin, if you can't get a response here, try him here  http://www.audiomaintenance.com  he's really good about answering emails, and has been helpful on his other stuff on other build threads. I really don't understand why this compressor hasn't gotten wheels yet??? It's only the same compression rig that was on the baddest drum track of all time..
[size=18pt][size=12pt] "WHEN THE LEVEE BREAKS"!!!! [/size][/size]  Hello??? Hello??? anyone Here??? :-\

Also, if i remember correctly(it's been a long time since i read the colouring book), its really important to step by step the calibration, i would zero(middle) everything out, and start over again?

Keep us posted, and good luck

T

 

[redmojosteve]

Thanks Tony. I'll follow your good advice. I bought the switches and transformers from Colin so I appreciate that he does reply quickly.
Like you, I can't understand why there aren't more of these out there compared to the GSSL and 1176, although the latter have been around on this fine forum for a while longer.
I'll get back to checking again soon.
Cheers
Steve

 

[tonycamp]

looking for some parts for this project? I'm gonna keep adding to this post, i'd rather give you guys some$, than parts houses. so here we go. Mostly fairchild transistors

I need 16 of these
http://www.mouser.com/ProductDetail/Honeywell/80555-01500150-05/?qs=%2fha2pyFaduh0WeltRahLM8FJCp%2fEe%2f%2fV7MMKKUI2t7iHfpJU1OpQCw%3d%3d

I need 22 of these
http://www.mouser.com/Search/ProductDetail.aspx?R=BC560BTAvirtualkey51210000virtualkey512-BC560BTA

I need 2 of these
http://www.mouser.com/Search/ProductDetail.aspx?R=2N3820virtualkey51210000virtualkey512-2N3820

I need 4 of these
http://www.mouser.com/Search/ProductDetail.aspx?R=2N3819virtualkey51210000virtualkey512-2N3819

I need 16 of these
http://www.mouser.com/Search/ProductDetail.aspx?R=BC184Lvirtualkey51210000virtualkey512-BC184L

I need 4 of these
http://www.mouser.com/Search/ProductDetail.aspx?R=BC184Cvirtualkey51210000virtualkey512-BC184C

I need 44 of these
http://www.mouser.com/Search/ProductDetail.aspx?R=BC182Bvirtualkey51210000virtualkey512-BC182B

 

[voitto]

Hi Tony,

I'm trying to source these parts also.

Farnell have a Multicomp BC182b order code: 1574375 - This is what I have installed in my board.

Banzaimusic.com have a BC549C (NPN 30V 0.1A 0.5W TO-102) part no: sku16579  Which I have purchased and was hoping to use as substitution for Fairchild BC184c

They also have 2N3819 - part no sku18397

perhaps someone with more experience could tell me whether these substitutions will work!

 

[tonycamp]

Excellent voitto, thanx for chiming in! I am working on these also, i've found some NOS on one item(not sure part # right now), but requires a 2000 piece purchase!

I'll report back once i figure it out, maybe we can get a few of us together to lighten the $ impact on being forced to buy mass quanities. I was not expecting these obsolete parts issues on this build?

thanx
T

 

[Dr Gris]

Hi folks,

Glad to see some interest in this. I don' t have the time or money right now for this beast,
but I' ll gladly take part in any kind of groupbuy of hard to get parts, that only sell in large quantities.
Or any hard to get parts. Let me know!

Do you guys get the cases and front panels from GroupDIY member "ddt"?
I' ve noticed that his front panel for this have changed from a square to a circular cutout for the meter :-\
I liked the square better...

Best
Magnus

 

[voitto]

Sounds like a good plan. I'd be up for chipping in for a group buy too. Perhaps Colin at AML has some of these parts in stock?

 

[tonycamp]

Voitto, whats your location?
I found these BC182b, not a bad price if we split them up, otherwise i'll have to build about 90 of these things! lol

http://components.arrow.com/part/detail/195445S9646499N7769?region=na

I'm going to dig in tonight again and see what else i can come up with?

 

[voitto]

I'm based in Finland. I'll also keep an eye out.
Thanks

 

[tonycamp]

(Best Ren voice)

Ok then Fella's,...........this post has been removed by "the history eraser button", because the part was wrong, and I am an EEEeeeeeeediot!!!

 

[voitto]

Hey Tony,
That's great news!
Looking at the link you posted I can't see this part in any of the BOM's I've been looking at. Maybe I'm missing something.

 

[touane]

Hello there, has anybody seen a datasheet for the VTB2311? This one does not seem to be included in the Carnhill design guide, and I have no idea on how to identify the wiring.

 

[tonycamp]

Hey Tony,
That's great news!
Looking at the link you posted I can't see this part in any of the BOM's I've been looking at. Maybe I'm missing something.

Good call Voitto! Ok, so i went through my BOM after stepping away for a bit, seems the above post,(deleted) was a phantom listing in my BOM??? :-[, I was tripping on what the "pressure switch" was going to be used for :?? I am going to order what is in my shopping cart for now, i know it isn't everything, but I'll have to make a subsequent order for what's left?

 

[voitto]

Hello there, has anybody seen a datasheet for the VTB2311? This one does not seem to be included in the Carnhill design guide, and I have no idea on how to identify the wiring.

The corresponding colors are marked on the PCB for this one and it looks like its matches with the VTB1847 in the design guide.

 

[shabtek]

got this back on the bench,
seems to be squashing nicely after initial calibration.
anybody have problem and need a reading/measurement while I got this opened up?

 

[0dbfs]

that's good news but not there yet. Certainly on the way though!

Cheers,
j

 

[Dr Gris]

got this back on the bench,
seems to be squashing nicely after initial calibration.
anybody have problem and need a reading/measurement while I got this opened up?

Could be a good thing for future builders......like me

How' s the gate/expander working? Useful??

Best
Magnus

 

[redmojosteve]

Just an update on my build.
Following a session with someone who is better at this than me, we noted some small but significant issues which have now been fixed. I had desoldered the input board some time ago but inadvertently damaged some through plating in the process! This has been corrected with a short wire link. I had a dry joint on one of the leads of the output transformer. It looked perfectly alright but resoldering it cured the problem. Finally one of the presets on the compressor board was wound right down to zero and this was stopping things. A useful tip I discovered here to set a starting point for a trimmer pot, turn it anticlockwise completely to its starting position and then wind clockwise about ten turns. This at least gets the trimmer within its working range so you get some useful signal through. Maybe everyone knows this but I obviously didn't and I'll know better in future. So there you have it, a problem at the front end, back end and the middle!
I ran through the calibration procedure a couple of times last night and I am getting good and sensible readings now. I'll run through it again tonight as it seems to be a process which converges on the correct setting after a number of sessions. It's then on to the second channel and fingers crossed for that one.
At last making real progress!
Cheers
Steve

 

[Slenderchap]

Excellent news.....

Colin
www.audiomaintenance.com

 

[redmojosteve]

Got the second channel working. I had made a mistake in placing an incorrect transistor in the input board (not the FET) and once this was replaced it worked satisfactorily. I haven't tried audio yet but that will happen in the next couple of weeks. Calibration doesn't seem too bad and makes more sense after you have done it a couple of times. To repeat something I mentioned earlier, unless the instructions advise otherwise, get any preset trimmers in a mid position otherwise you can be chasing your own tail wondering where the signal is! One of the practical problems I had was that my sig gen isn't so good a low levels. I could have set up a simple arrangement on a breadboard I guess but I have invested in more sophisticated audio signal generator (my current one was only £5 off ebay so I can't complain).
Thank you for the help and advice on this project as it has proved to be invaluable.

Cheers
Steve