Feeler: ez760 - Compressor/Limiter/Expander/Gate

[envelope]

Hi Colin, can you recommend possible part numbers/sources for these guys?

F1, F2 = Ferrite Bead (2)

CL1, CL2 = LC Network 100pF (2)

and

Are the 10K and 47K LOG P20 series pots, Omeg part number LA20BU? {photo below}. Cheers!

EDIT: thanks for the info update (see post below this one)

 

[Slenderchap]

Don't know why they are missing from the parts list...

The ferrite beads F1 & F2 are Farnell 9265236

The 3 terminal capacitors are Rapid 26-6182

However, they are only their to comply with EU EMC regulations (which don't apply outside the EU.... or for anything built for personal use).... so you can simply fit wire links instead.

The pots are LA20BU's.... they came in stock the other day (along with the Lorlin switches)... just haven't made it into the store yet.... they will be in a "kit" along with the output transformers (which are expected on Friday).

Colin
www.audiomaintenance.com

 

[Davo]

Hi Colin,

What parts will you not be supplying with your kit?.. switches, knobs etc.  and when do you think that it will
be available

Thanks!
Dave

 

[Slenderchap]

Dave,

It will only be a simple kit... transformers, rotary switches, pots, ribbon cables, knobs (I'll look into the toggle switches and LEDs)..... I would like to say that I'l do it tomorrow, but I know it won't work that way !

The colourbook has now got the calibration procedure in it at the end.

Colin

 

[Davo]

Thanks Colin, smart of you...  No point going mental counting resistors! 
I'm just gonna order the xformers and pots then.....  I'm not finding the VTB2311 on your site, is that in yet?

dave

 

[tomcat]

Me too. Xformers and Pots, rest seems to be easy to get.

Thanks Collins for this nice project!

 

[Infernal_Death]

Got some questions regarding this project.
- Is it possible to order only part of the stuff you plan to offer as a kit ? I don't need the switches and i want to use my selection of knobs, however i need the pots and transformers.
- BC212B and BC212L are not available anymore at Farnell. Any recommendations regarding substitutes ?
- Are the standoffs regarding the frontpanel really necessary ? Isn't it sufficent to mount the control board via the switches itself on the frontpanel ? Would make ordering a frontpanel much easier.

Oh and of course thank you for releasing this project. Layout on the boards looks very cool and i really like the building blocks on different, separate boards, connected together through one motherboard. Nicely done !

Flo

 

[lsskmki]

- BC212B and BC212L are not available anymore at Farnell. Any recommendations regarding substitutes ?

Various places to get the BC212L: futurlec, rapid, possibly RS or maybe there is some available in Ebay. It's possible to use BC212L instead of BC212B and just bend the legs to get the pinout "corrected".

Btw, just finished sourcing the last parts (not counting xfmrs) for this project and it seems Vishay BC 15uF caps are getting scarce. Only Farnell seems to have them.

 

[tomcat]

A few questions regarding the BOM:

1. Is there a reason for the brand/type of electrolytics in the bom? Most of them are series 2222030 which is rated +50% -10% tolerance. The other series 2222021 (like the 220uf) is rated +/- 20%.

Btw. the missing part no for the 100uf/25v is 1165423 (series 2222030)

---

2. Wima Poly: 2n2/5mm, 4n7/5mm

Both seem to be EOL (regarding to farnell) ... will 2.5mm (mks02) fit or just use FKP types?

---

3. The partnos for the Lorlins refer to "shorting types". Is this correct? Most of the time non shorting versions are required

---

4. Toby THS08RRAF 8pin R/A pin header ???

This: ?

 

[Slenderchap]

You should view the build guide as "this is the way we did it" rather than "you have to do it this way"..... the component choices are generally based upon the items we have in stock or what was easiest to get....

.... just use the parts that will fit/work.....

The right angle header is an 8 pin version of what you have there... if that photo is from Toby's website then I guess that they have just shown a generic photo for all sizes.

Rather than bothering with a kit we'll just put parts individually..... some are there already.

Colin
www.audiomaintenance.com

 

[tomcat]

Thanks colin. Do you have also an answer to question no3?

 

[Slenderchap]

Either shorting or non-shorting will be fine as all it is doing is adjusting the timing constants and levels in the sidechains..... the choice was based on ease of availability.

Colin
www.audiomaintenance.com

 

[tomcat]

Thanks Collin!

 

[pachi2007]

Is it ok to use 1/4w resistors? 0.6w is posted at BOM

Thx

Pachi

 

[Slenderchap]

0.6w is just a standard for 1% metal films ..... without actually measuring all the voltages involved I cannot say for sure..... but I would be very surprised if 1/4 was insufficient.... the powers involved are probably miniscule......

Colin

 

[reanimatorstudio]

Hi Colin,
I have the original version without tranny's. What would be the difference if I put those you suggested in?
Does it change the in and output gain?

 

[Slenderchap]

If you just want to add Carnhills to an original F760 etc you would use the VTB9071 (10k:10k) on the inputs and VTB2281 (600R:600R) on the outputs.

Colin
www.audiomaintenance.com

 

[gurkan75]

Reanimatorstudio: I think I have a technical note from ADR  of that somewhere.. If I remember correctly, you should wire the primaries on the output tx in paralell for a little step-up & more headroom, + remove a gain setting R.

Pm me your emailaddress and I can send it to you?

I believe equalizers and such used 1:1 on output.

/Johan

 

[envelope]

Here is a diagram,  from the 760 manual, regarding the 600Ohm output transformer step-up arrangement

 

[gurkan75]

Yes, thats the one, thanks envelope.