5003 eq building and help.

[dandeurloo]

Bump?????????????

OK,

I did the best I could on this.

Here's a Mouser cart with the parts that weren't included in Peter's kit. Save the pots:
http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=546ee9f29d

Please anyone feel free to make suggestions/alter this if something won't work, it would be much appreciated.

I tried to size the caps to work, some of them may be too big, but it's all they had in stock.

My other question was about the IC. I put TL071 and 5534 on there (assuming they are the correct parts) and some 39pf caps for the option cap. But, what's the difference?? I'm assuming 5534 is better because it's more expensive? I'm probably going to take the TL071 off the list, but just for reference.

Jeff, will the switch caps you stock work for the switch? What about your PCB mounting hardware?

cheers all
Eric

Try this one.  I haven't fit everything yet but all the caps should fit and are slightly larger.  So, its kind of an upgrade to Johnnyscotch list. Not sure if it will matter.  Still looking for Pots that will work the best.  Also, its got enough stuff in the cart for 4 kits.  

http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=21fbc5f721  

OPA604:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=OPA604AP-ND&itemSeq=89381535&uq=634171267002373997&cshift_ck=2024025388cs511524484&client_id=5042

Possible pots:

http://www.mouser.com/ProductDetail/Alpha-Taiwan/RV16AF-10-15R1-B10K-0C/?qs=vCz78MyBKmrtgpyLTT%2fC9Q%3d%3d

 

[johnnyscotch]

Bump?????????????

OK,

I did the best I could on this.

Here's a Mouser cart with the parts that weren't included in Peter's kit. Save the pots:
http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=546ee9f29d

Please anyone feel free to make suggestions/alter this if something won't work, it would be much appreciated.

I tried to size the caps to work, some of them may be too big, but it's all they had in stock.

My other question was about the IC. I put TL071 and 5534 on there (assuming they are the correct parts) and some 39pf caps for the option cap. But, what's the difference?? I'm assuming 5534 is better because it's more expensive? I'm probably going to take the TL071 off the list, but just for reference.

Jeff, will the switch caps you stock work for the switch? What about your PCB mounting hardware?

cheers all
Eric

Try this one.  I haven't fit everything yet but all the caps should fit and are slightly larger.  So, its kind of an upgrade to Johnnyscotch list. Not sure if it will matter.  Still looking for Pots that will work the best.  Also, its got enough stuff in the cart for 4 kits.  

http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=21fbc5f721  

OPA604:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=OPA604AP-ND&itemSeq=89381535&uq=634171267002373997&cshift_ck=2024025388cs511524484&client_id=5042

Possible pots:

http://www.mouser.com/ProductDetail/Alpha-Taiwan/RV16AF-10-15R1-B10K-0C/?qs=vCz78MyBKmrtgpyLTT%2fC9Q%3d%3d

WOW, thanks a ton!!

I'll repost it over in that other "mouser order" thread in case anyone wants to use it.

I'm going with the TAW "pots kit". It's reasonably priced I think, for such a PITA part. I got an email from Laura saying they just got a bunch of them from Omeg. If it drives me crazy not having the center detent, I might change them out if you guys get a group buy going.
Just tired of sitting on this, it's been too long. I want to hear them!!

thx again

Eric

 

[fazeka]

I just ordered a set. I'll let you know how it turns out.

 

[dmp]

I just started soldering and noticed the pcb has some differences from the schematic
For the MF band, the component values on the pcb (three caps in parallel for each one) add to 38.7nf and 56nf, while the schematic says 39 nf, and 27uf. The schematic over in the lab thread had a 56nf as a 2 kHz band though
The caps around the 2520 (c3,c4) are 180pf on the schematic but 100pf on the pcb. Looking up the API 553 schematic, should probably be 180pf. Also, the C6 on the LF band looks like 47uf, not .47 uf, but maybe that is to raise the LF corner.
And a minor difference, the layout of the bands are slightly different - the switch lifts R8,9,10 from ground instead of the pot to the inductor...
Now - off to learn about these "swinging input, opamp-based L-C equalizers"

 

[darnell]

Just got mine today.  2 5003's with inductors, trannys, and metal and parts kits.  Very excited!!! 

Any thoughts on adding an additional freq to the mid and low bands?  Or is that beyond the scope of what this is designed for?  I realize it may just take a new switch, cap, and resistor. But will it muck up what this is intended for, freq wise?  I have to admit, the mid freq are not a range I really use too often  :

Anyway, very excited to get going on these.

d.

 

[Joechris]

A nice thing with this project is that there is a lot of posibilities to experiment with different caps/freq. If there was space enough I would like a rotary for the mid eq. But it isnt that hard to implement a toggle with midle stop to add three frequensis. Take a look at the quad8 or Opamp labs schems, and this http://www.opamplabs.com/cfl.htm
Any news on the pots?
j

 

[pjdiy]

Pots are here,

http://www.audiomaintenance.com/acatalog/om-01-057_extended_info.html

 

[johnnyscotch]

I just started soldering and noticed the pcb has some differences from the schematic
For the MF band, the component values on the pcb (three caps in parallel for each one) add to 38.7nf and 56nf, while the schematic says 39 nf, and 27uf. The schematic over in the lab thread had a 56nf as a 2 kHz band though
The caps around the 2520 (c3,c4) are 180pf on the schematic but 100pf on the pcb. Looking up the API 553 schematic, should probably be 180pf. Also, the C6 on the LF band looks like 47uf, not .47 uf, but maybe that is to raise the LF corner.
And a minor difference, the layout of the bands are slightly different - the switch lifts R8,9,10 from ground instead of the pot to the inductor...
Now - off to learn about these "swinging input, opamp-based L-C equalizers"

I noticed some differences in the schemo as well, but not being an EE, I just attributed it to different revisions.

Can anyone confirm that it will work properly and with minimal problems using only the values printed on the PCB??
PeterC, maybe??

cheers
Eric

 

[dmp]

I just tried Omeg ECO 10k lin pots that I had leftover from another project and they fit perfectly.
Just took the afternoon off and soldered one up - and... it's working!
Because the bypass turns off the EQ filters, I don't think I'll go out of my way for center detent pots.
I couple more things I noticed - to ground the L bracket to the chassis pin, I'm going to run a wire to a lug on one of the connecting bolts. Also, I don't think R6 will typically be installed, which connects chassis to audio ground. This connection is typically in the psu, unless I am wrong.

 

[mylesgm]

The Eq works perfectly following the pcb parts designation, I've got two working here.  Only issue is that there is an 8db gain reduction from unity and I'm not sure wether that is my opamp choices (yamaha 80200 and signetics 5534) or a gain setting in the eq.  Sounds fine and until peterc gets back to me about it I'm not bothered.

M

 

[dandeurloo]

are we suppose to use the optional cap with the OPA604's?  Anyone using it?

 

[peterc]

I dont think there is an issue with the 604. It is only the 5534 that is unstable at unity gain.

Peter

 

[mitsos]

You definitely don't need the compensation cap with the 604.  Pin 8 on the 604 has no internal connection. But if you already soldered it, you don't have to remove it, and with it installed you could test both the 5534 and 604 to see if you prefer one or the other.

 

[dandeurloo]

mitsos, good point about comparing!

 

[dmp]

I have unity gain with mine, but I used a line input transformer instead of the active balanced input.

 

[jsteiger]

I have unity gain with mine, but I used a line input transformer instead of the active balanced input.

Ah ha...cheater! 

 

[mitsos]

I have unity gain with mine, but I used a line input transformer instead of the active balanced input.

which one? what ratio?

 

[dmp]

Cinemag CMLI-15/15b (1:1)
I wasn't sure if it would work because I thought some eq circuits need to be driven from a buffer, but it seems to be fine.
I haven't drilled holes to mount it to the pcb yet, but it will fit.

 

[dmp]

Myles,
I think you have two of the secondary leads swapped on the output transformer, which would explain your reduced output.
I think the output should be (from top to bottom)
red
gray
green
blue
yellow
purple
The picture you posted looks like yellow and purple are swapped.
The primary is, from top to bottom (to have in-phase output)
red
brown

 

[mylesgm]

Thanks dmp I'll fix that.

Who is Laura at TAW and what contact details?  I'd love to get the correct pots...

M