Barry Porter "Net EQ"

[dagoose]

knock knock.. king-rb.. you still there or are you too busy playing with your new eq. 

 

[kpearsall]

also curious about which parts will fit the boards for relays and inductors Let's keep this thread going!

 

[dagoose]

also curious about which parts will fit the boards for relays and inductors Let's keep this thread going!

I just ordered the relays from RS that i mentioned earlier and they will do the job. Nice and small relays.  8)
I didn't really check for the inductors to be honest but it's just a LC on the input, nothing spectacular.

 

[kpearsall]

Thanks I have to finish up some API's and u87's before I really get things going, but I'm ordering bits and pieces for it when I place order for repair work. Can't wait to finish it though. My Orban is really flexible but I'd never use it on the master!

 

[dagoose]

Getting there slowely. Boards are 80% stuffed and most of the parts are in. Working on the PSU, just need a board for the +/- 18v with lm337/317.
Now it's time to get working on the stepped switches and the rest.

 

[kpearsall]

I'm just going to use the PSUniversal from diypartssupply and not populate the 48V section. I'm deciding on my stepped switches right now. Might as well make this mastering quality.

 

[dagoose]

Just wondering about the 100uf and 1000uf caps in the audio path. They should be bipolair according to the schematic but i think that regular elco's will do the job as well don't they? Bipolair caps that will fit from 100 and 1000 are hard to find.

 

[kpearsall]

A lot of designs are like this. I've repaired a few pairs of Quested monitors that have these for the same purpose. I've heard everything as a reason. Most often I'm told it's something to do with Linearity of the AC signal.

I'm using these parts:

For 1000uF: http://www.mouser.com/Search/ProductDetail.aspx?R=ECE-A0JN102Uvirtualkey99990000virtualkey667-ECE-A0JN102U

For 100uF: http://www.mouser.com/Search/ProductDetail.aspx?R=UVP1A101MEDvirtualkey64700000virtualkey647-UVP1A101MED

the 100uF is a little under voltage but I think it would be ok there. If not I'll probably have to go polarized too.

The lead spacing on either isn't perfect, but it's close enough where it won't bother me

 

[dagoose]

I was checking out the stepped swithces for the frequencies using out the sheet that Harpo did but than i found out that it's not really easy to convert it from 11 steps to 23 steps, the way i want it.
Gain is no problem and so is q but the frequencies are out of my really bad excell skills.
Anyone? maybe Harpo can hop on?

 

[Harpo]

Hop  ;D

 

[dagoose]

Harpo, you are a hero!  8)

 

[kpearsall]

Very cool Harpo! I guess there is hope for having a stepped attenuator for lift/cut without needing a switch

 

[Harpo]

latest Hop updated for your +/-dB idea ...

 

[kpearsall]

Harpo I am in awe of your skills Thank you so much. This project has definitely hit the top of my personal build list!

 

[dagoose]

some progress here:

Boards stuffed, psu ready (ok.. need to mount it on some cooling), switches coming in this week and than the fun begins  8)

 

[kpearsall]

looking good! I don't even have the boards stuffed yet! Is that a three space rack unit? I was wondering about making mine bigger. It's gonna be a tight fit at 2U with all those knobs and switches.

 

[dagoose]

yep, 3u it is
I will make it fully stereo and with stepped switches it won't fit in a 2u anyway or will at least be really tight.

 

[kpearsall]

have you found any good quality/low cost switches? This is gonna become a very long term project if I have to pay 30 bucks a switch

 

[Harpo]

30 bucks (for a 2x24 rotary switch?) might already be low cost.
Below listed some manufacturers of >12pos.multideck/pole rotary switches, ask for quote/distributor.... (beware prices might get astronomic...)
electroswitch
cole
seiden
elma
shallco
chiefdom

 

[dagoose]

wow! never seen some of those switches before. Nice to know
I have used palazzo switches on my stepped sontec (http://www.dagoosemusic.nl/?p=ultimate-eq) and they are cheap and pretty good actually. Maybe not as good as elma's but they are about 20% of the price of an elma so it's a nobrainer for me. My switches came in yesterday so zen soldering time again  8)
http://www.uraltone.com/kauppa/product_info.php?products_id=1078
I posted somewhere on the board about modding those switches for setting the stoppoint without opening it up. Have to dig it up.