[BUILD] CAPI LC53A~500 Series~Love Child EQ Kit~Official Support Thread

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Wow,congrats Chuck!

I´ve only done 2,wish I had the money to fill up to a full rack with them ;D
Please post what you think about the different DOAs (mine have gar2520s).

Cheers,

Udo.
 
kante1603 said:
Please post what you think about the different DOAs (mine have gar2520s).

I'm curious to hear your thoughts about the DOA differences too.  About to start a build soon  ;D
I have enough DOAs on the way to test a few different configs but curious to hear your report on the results between the two.
 
sadly i'm deaf, and can't hear the difference as of yet.  Also, my room has too much outside noise for me to hear anything clearly, to be honest.  but soon i'll pull the AC out of the window, and be able to close the window and listen without all of that outside noise pollution comin' thru.   
 
Hello,

I'm super excited to have this eq completed soon! I have my power supply pcb build to the point of needing to calibrate the cmrr and was hoping someone might be kind enough to verify my method before I dive in. I've garnered information from the assembly aid, the vc528 cmrr guide and from this thread to devise the following plan:

- Connect "special cable" to signal generator with +/- 500Hz sine wave. I'm assuming I can use a plug in my DAW as a signal generator.
- Adjust output for 1 volt AC as measured using a DMM with red probe to pin 2 and black pin to pin 1 of special cable.
- Connect special cable to card edge (input) of power supply pcb: I plan to use my API 500V as a power supply with the pcb inserted into the first slot and simply connect the cable to the xlr input. I'll empty it of all other modules and position it for the "easiest" access to the pcb. Please let me know if this is bad.
- Connect to input of DAW via XLR with other end of cable altered with aligator clips, etc... to connect pin 2 to negative side of C2 and pin 1 to the common terminal of A2, being sure to have installed a known-good op amp into A1. It's my understanding that I may have to also connect pin 3 to the common terminal of A2 if I don't see a signal.
- Power up and follow adjustment instructions.

I'd be grateful if anyone could give me the thumbs up on this approach or point out any flaws/suggestions.

Thanks!

Jason 
 
Thought I'd share my completed build :)

Definitely my most intense build to date but it works perfect right out of the gate! Sounds superb! HF section, especially, is clean and musical. Even extreme boost levels maintain a usable/musical timbre. Can't wait to patch it into a mix!

Props to chunger for his excellent build guide in this thread; saved me a ton of time. Of course, thanks to Jeff for such a well engineered kit! (btw - when do we get a 525 or 527 clone?  :D)

Cheers!

Jason
 

Attachments

  • lc53a_down_res.jpg
    lc53a_down_res.jpg
    97.6 KB · Views: 62
I had a VP25 on 10/2011 and I bought a LC53A EQ kit on 11/11/2012 and Jeff asks me to share my experience.
It took 10 days to have the EQ at home in the South of France with 127$ of custom fees.
It took me around 8 hours to have evrything built.
I do not have real difficulty. The documents Jeff sent to me are very precise, everything is explained.
I can just confirm the problems with CTO5 and DF.2 amps sockets. It may be easier with largerpads to warm first the pad. I have the feeling that the control of the soldering would be easier. For GND sockets, they may be easier to solder if the pad is connected to GND with a 5mm conductor instead of several very short conductor around the pad. The heat may not go into the GND as fast. Those are just ideas, not fully sure that they would work. Let me know your advice.
I confirm also that a CHP-170 cutter is mandatory. I bought an equivalent here in France and I added also pieces of protective paper on both sides to avoid any contact between the PCBs and the metal cover.
2 last minor points:
- I know it is a lot of work to do but I'd like to have schematics. I like to understand what I am doing and it helps also in case of problems.
- My old eyes hardly read the blue on dark writings on the face plate. Please, don't suggest a 500++ format just like those big phones with big numbers for very old people...

Now the best: the sound!!!!!..... It is simply perfect to me. I do not know the right words in english. Anyway, even in French, I have difficulties to explain... Let say clear and punchy.

I have to say thank you to Jeff for that very good job you do.



 
alrighty... here's an example of these EQs in action... they were used on the drum bus in this mix. (if i remember correctly). probably a push at 3k and 50hz. love 'em!!

http://www.youtube.com/watch?v=HqybvZdLUZY


-pete
 
I think it would be great to see some frequency plots of this EQ using different OpAmps so we can see the sonic differences, since I pretty much can't hear the differences between the 2520 and 1731 in this.  I have 2 configured with 2 2520s, and 2 configured with a 2520 and 1731.  :-/ 
 
Chuck, I would guess that freq. sweeps would essentially look identical. I can currently only print out one B&W sweep result at a time with my AP Portable One. As soon as the System One arrives I will create some nice color pdf's for ya. I have been wanting to do this for some time now. Maybe not hearing a dif is a product of your monitors? Just wondering....dunno what you use.
 
i use Focal Solo6Be's and a symphony I/O.  it's pretty top notch!  however, i live in NYC with drafty windows and noisy streets and above a chinese restaurant, where the ventilation fan for their kitchen sits above my apartment, shaking the place at roughly 70hz from 11am til 11pm, 7 days a week, except for friday and saturday, when they're open from 11am - midnight lol
 
Hey Chuck, do you like chinese food? Hey, why don't you swap the1731 and 2520 from the pertinent 2 units and make a fully loaded 1731 eq? see what she sounds like, and report back at 0-800 hrs soldier! ;)
 
Just wanted to say that currently, my favorite uses for these guys are on the mix bus in a Mid/Side config feeding a pair of VC528s. 

Also, once I figure out how to do overlays with SpectraFoo, i'll post some pics of how the OpAmps compare, frequency-wise
 
Spectrafoo:  snapshot, that opens a window that lets you select which to display where.  Manually drag them around.  Clicking on one in the window again lets you change ID, etc. 

I charted these and the TB550A, the extreme low end is pretty different between those two types, both using GAR2520's.  Chart in next post!

I doubt you will see frequency difference in a response chart.  If any, likely small difference on the bottom end below 20-30.  I'd look at noise and harmonics, which is tougher to separate. 
 

Latest posts

Back
Top