DC Uni-Q. Bugagaga!!!!

[Igor]

Start guessing

The hint: after freakin' with switches and Sontec, I took absolutely different direction.

Ordered 2 ugly proto boards just to check the idea. f**k it up, it works!!!!

Still have to fill some... gaps! Program is 90% ready, we are at truth tables filling stage.

Sorry, no funny features like USB (yet)

Will post the pictures of stuffed boards soon. These boards are just proto, the final thing will look different.

 

[tomas1808]

AD/DA Converter? 

 

[deuc224]

beat me to it!!! ;D

 

[grantlack]

sorry guys, not an adc.  my eye tells me it's a mastering eq with ic and relay-based switching of the resistor network and other bells and whistles.  as always igor, well done and excited to find out more details.

 

[goldvasser]

Rhaaa ! Relay-based-pic-controlled EQ .....
:-* :-* :-*

Just IRRESISTIBLE !!!

 

[Igor]

Yep. Here are the news.

For now, I got 2 working "bands".

First, VSF-based, which can be LPF, BPF, HPF; cut up to -35, boost up to 14 db;
HP/LP can be from 4db/oct till resonant 22 db/oct; like a plugin, but analog.
Second  - Sontec low band. 18...800 Hz, LP/BP.
8 steps of Q; 31 steps of gain (and "band off"); 28 frequency's.

Have to test the rest of Sontec bands; than Neteq/ISA110. Maybe, will do filter of SSL channel EQ.

This final EQ will be done at universal motherboard which can handle 2 channels, up to 7 filters each one,
"summing" boards, input/output boards, and MS/level board delivered from K-1.

Trying to keep it flexible as possible but not overcomplicate.
The idea is to combine different EQ's as well.

Say, Sontec and Neteq are "parallel" design but different filters types, different gain control;
however, one glance at both schematics and we see, there are many common things!

I want to keep everything in 2RU. User interface will be simple:
not like Bettermaker (I cannot understand what goes here, besides I sure it is good), but like Max BCL.
All parameters can be seen at same time.
Each band has its GAIN, FREQ, Q control, displayed on corresponding 7-seg. LED display.
2 EQ channels can be linked or separated.
This way, up to 7 bands, level/MS (optional), memory's.
CUT filters (LPF/HPF) can fit at one band's slot.

Audio wise, there are lot of benefits of use of relays over "traditional" ELMA's.
More steps and total recall; hermetically sealed contacts; no wires fron audio to front panel
(relays can be placed as close as possible to filter they control).

For 2 bands of stereo EQ, the mathematics are next:

32 relays plus microcontroller, LED displays and other stuff aprox. $90
2 dual, 2 single ELMA's and something less fancy for Q control: about EUR160.

Complicity - yes, control board with uP/displays/rotary encoder added, but soldering resistors/relays bit less work than in case with ELMA's.

Well...stay tuned. Will upload some new photos soon as I got the camera to workshop.

 

[radiance]

Interesting ...would it be possible to make the relay footprint so it would accept both smt and trough hole relays?

 

[Nobru]

Wonderfull!!! 

 

[e.oelberg]

This all sounds great Igor ! This is going to be my next project!! I love the idea, allready wanted to do it with a kleine + hummel ue100 design.
With clever resistor networks you may even not need so many relays though !  how have you implemented it ?

nicholas

 

[dagoose]

sounds really interesting!
Count me in!  8)

 

[ptron]

Me too!

Is this a "noob friendly" project? Probably not but i like to be optimistic

Sounds like an amazing project as usual igor we are not worthy! thank you very much

 

[detonator]

Just love the idea

 

[Marcocet]

Igor, you really don't screw around. I'm very in to this one.

 

[DOMC Mastering]

Chuck in a niveau filter

 

[Sylvain D.]

What can I say

 

[cstella]

Very cool! 

 

[creal]

very nice, count me in.

 

[Igor]

And...

Here are some photos and front panel design!

The front will look kinda:

Hi-res:

http://i251.photobucket.com/albums/gg291/diy33609/DC_UNI_Q_PRELIM/front.jpg

With freaky switches, digital control ready - until we fixing last bugs in software and me getting red-eye syndrome
filling the truth tables with 11000101100100100100111,

Uni-Q Filter under test:

Meanwhile, we get program working on proto board, it still has no communication with memory chip,
sometimes even hangs on, but we'll fix it soon:

Ah yep, what is the thing causing red-eye syndrome? Yep, right answer is "Coding!!!", not cannabis:
(with showing off the programmer's - Vladi Kulikov's - thumbnail!!!!!)

Than, progress on front panel:

Half of motherboard:

(not finally routed yet)

Sontec Filter with 16 relays:

(not finally routed yet)

 

[Igor]

Interesting ...would it be possible to make the relay footprint so it would accept both smt and trough hole relays?

I used 5V DPDT relays guaranteed for 500000 cycles.
They are arround $1.40/relay for 100pcs in local electronics supplier store, price falls to $1.10 for 1000 pcs.

SMD relays are more expencive.... however, if you stacked with thousands of good quality relays and need to get rid of them, I can adapt the boards for both types.

 

[Igor]

This all sounds great Igor ! This is going to be my next project!! I love the idea, allready wanted to do it with a kleine + hummel ue100 design.
With clever resistor networks you may even not need so many relays though !  how have you implemented it ?

nicholas

Hm. Say, for 31 steps of gain + off we need 5 of DPDT relays, to make kinda lin centertap centerdetent pot.
For 24 steps of FREQ, we need at least 6 DPDT relays, this way, 64 steps lin pot approximated down for log pot characteristic.
For 8 steps of Q, 3 of DPDT relays used.
For Filter TYPE and OFF, 2 DPDT relays are used.