Poor Man's Pultec EQP1-A

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buschfsu said:
any chance of getting two boards?
thanks

All the current order are spoken for I am afraid but there's a list in the Black Market for those who want to place an order for the second run. It's up to over 100 PCBs already so your best bet is to express your interest on that thread and I'll add your order to the rest.

Cheers

Ian
 
The 210 PCBs have arrived!! I have just soldered the switch into one of them to make sure it fits and the connections are correct and all is OK. So I shall start shipping tomorrow. Below is a copy of the list of purchasers and I will change paid to shipped as  I ship each one:

Code:
  Handle             Quantity        Price (gbp)
ej_whyte              2 sets            shipped
Joechris              2 sets            shipped
Albrebreton           2 sets            shipped
chrispbass            4 sets            shipped
culteousness1         2 sets            shipped
strangeandbouncy      2 sets            shipped
michalk               1 set             shipped
mylesgm               4 sets            shipped
zebra50               2 sets            shipped
tomugli               2 sets            shipped
Kamel                 4 sets            shipped
Audiohammer           2 sets            shipped
guze                  2 sets            shiooed
Andreas Pfeiffer      2 sets            shipped
noulou                2 sets            shipped
mrclunk               2 sets            shipped
Holger                2 sets            shipped
Matthew Jacobs        4 sets            shipped
danijel               4 sets            shipped
Grooveteer            4 sets            shipped
kante1603             4 sets            shipped
0dbfs                 4 sets            shipped
3nity                 2 sets            shipped
Hank Dussen           2 sets            shipped
Citrus Hill          10 sets            shipped
baadc0de              4 sets            shipped
bovox                 2 sets            shipped
menigu                1 set             shipped
Michael Tibes         4 sets            shipped
Ptownkid              2 sets            shipped
Davo                  1 set             shipped
tzman                 2 sets            shipped
MathisD               2 sets            shipped
benlindell            4 sets            shipped
hodad                 2 sets            shipped
peterc                2 sets            shipped
desol                 2 sets            shipped
creal                 2 sets            shipped
   


Cheers

Ian
 
My boards arrived this morning! Looking very nice :)

Like to say thanks to Ian for all the effort you put in, and all those envelopes you have to post :eek:

Cheers
 
OK, I have shipped all the first round PCBs now except for guze and gevermil.

Edit: guze I have your shipping address now and your boards have been shipped.

gevermil has unfortunately had to drop out.

gevermil dropping out means I have two spare sets so Davo it is your lucky day because I have shipped you the 2 sets you wanted all along. It also means there is a set for me so I can build the circuit and check it out myself.

Enjoy!

Cheers

Ian
 
Hi Ian,



  you bloomin marvel . . . I hope you used self-sealing envelopes, that glue really tastes disgusting after just a couple of envelopes . . .



  I think i speak for one and all, Thank You, and we are all very excited . .



    ANdyP
 
So, know that i have the boards  :) let me just clear up the jumpers/resistors.

Hi Switch:
R1 & R2 in
R3 Unconnected
Jumper L1 (assuming i don't want the inductor)

Low Switch:
Jumper R1 & R2
R3 = 56k
Jumper | near to R3
Jumper L1

Correct?

Also, here are my updated values for using stepped gain pots. I used 40dB as you suggested, and the graph curves seem much better.

Thanks again for the boards

Cheers,
 

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ej_whyte said:
So, know that i have the boards  :) let me just clear up the jumpers/resistors.

Hi Switch:
R1 & R2 in
R3 Unconnected
Jumper L1 (assuming i don't want the inductor)

Low Switch:
Jumper R1 & R2
R3 = 56k
Jumper | near to R3
Jumper L1

Correct?

Yes, that seems right to me.

Also, here are my updated values for using stepped gain pots. I used 40dB as you suggested, and the graph curves seem much better.

Yes, they look good to me, the resistance is about 10% at the half way point as expected.

Just a note about capacitors. The PCB is laid out for 5mm pitch capacitors and I have checked that WIMAs are available in this spacing at the values required and at suitable voltage ratings (50 to 100V). However, where two capacitors are required, if one is a high value (say 330nF) it may not be possible to fit both side by side. Fortunately, the PCB is double sided so you can one on the other side of the PCB. I would like to claim I thought of this when I designed the PCB but I have to admit it only occurred to me later.

Cheers

Ian
 
ruffrecords said:
ej_whyte said:
So, know that i have the boards  :) let me just clear up the jumpers/resistors.

Hi Switch:
R1 & R2 in
R3 Unconnected
Jumper L1 (assuming i don't want the inductor)

Low Switch:
Jumper R1 & R2
R3 = 56k
Jumper | near to R3
Jumper L1

Correct?

Yes, that seems right to me.

Also, here are my updated values for using stepped gain pots. I used 40dB as you suggested, and the graph curves seem much better.

Yes, they look good to me, the resistance is about 10% at the half way point as expected.

Just a note about capacitors. The PCB is laid out for 5mm pitch capacitors and I have checked that WIMAs are available in this spacing at the values required and at suitable voltage ratings (50 to 100V). However, where two capacitors are required, if one is a high value (say 330nF) it may not be possible to fit both side by side. Fortunately, the PCB is double sided so you can one on the other side of the PCB. I would like to claim I thought of this when I designed the PCB but I have to admit it only occurred to me later.

Cheers

Ian

Ok cool, thanks for the clarification.

I was just looking up all the caps on mouser, they have them all in stock except the 2.2nF and 330nF :/ Also, most of the caps are 63 or 100v, but with the smaller values they only had 630v in. I know its perfectly fine to have a higher value than required, and i thought the only disadvantage to larger voltage ratings was physical size, but i just wanted to check there wouldn't be any significant noise increase or any other disadvantage?

With 2 sets of caps for stereo, they come in at £23.65 by the way.

Cheers
 
ej_whyte said:
Ok cool, thanks for the clarification.

I was just looking up all the caps on mouser, they have them all in stock except the 2.2nF and 330nF :/ Also, most of the caps are 63 or 100v, but with the smaller values they only had 630v in. I know its perfectly fine to have a higher value than required, and i thought the only disadvantage to larger voltage ratings was physical size, but i just wanted to check there wouldn't be any significant noise increase or any other disadvantage?

With 2 sets of caps for stereo, they come in at £23.65 by the way.

There should be no noise issues with higher voltage caps.

You did not mention what tolerance and make of caps you were looking up on Mouser.

I tend to use Rapid, which has the 2n2 in a WIMA but also is lacking the 330nF


Cheers

Ian
Cheers
[/quote]
 
ruffrecords said:
There should be no noise issues with higher voltage caps.

You did not mention what tolerance and make of caps you were looking up on Mouser.

I tend to use Rapid, which has the 2n2 in a WIMA but also is lacking the 330nF


Cheers

Ian

WIMA MKS4, 5% when they had them, otherwise 10%, did they have them all in 5% at rapid?

Cheers
 
ej_whyte said:
WIMA MKS4, 5% when they had them, otherwise 10%, did they have them all in 5% at rapid?

Cheers

No, they only have the 10% at Rapid.

They have 5% by other manufacturers but not WIMA.

Cheers

Ian
 
MKS2 i meant sorry.

RS has the 330nF in, but something wierd is going on with their website, whenever i try to add them to my cart it says 1 item in cart, price £0.00, and the cart is empty when i view it :s

Cheers
 
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