3D "AIR" EQ - "Night EQ" PCB's Complete!
- Thread starter khstudio
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Harpo
Well-known member
[quote author="khstudio"]
I was hoping the resistor had something to do with the Linear supply.
Could you recommend a Value & Voltage for this? I'm not sure how important this would be to add or not?
[/quote]
The reason for this resistor is to set the min load for the switching supply.
On page 1 you linked to the answer :wink:
[quote author="khstudio"]
Here is the (pre-made) power supply they use:
(I will be upgrading to a Linear PS)
http://www.ipdpower.com/catalog/product.asp?id=378 [/quote]
This supply is most probably SRW-45-2007, +18V/1,5A on output 1 and -18V/1A on output 2. Scrolling down the Application note mentioned a min load of 10% on output 1. (18V/150 ohm=120mA + load of the eq-circuit to archieve this min load of 150mA).
For your non switching power supply with regulators 7818/7918 or lm317/lm337 you don't need this resistor. It will only pull power and heat up your room. Just leave it out.
Your load caps 1000uF/35V will be fine. Rule of thumb was 1000uF per 1A load. This 5 OPamps will hardly draw that much current, so you're on the safe side.
I was hoping the resistor had something to do with the Linear supply.
Could you recommend a Value & Voltage for this? I'm not sure how important this would be to add or not?
[/quote]The reason for this resistor is to set the min load for the switching supply.
On page 1 you linked to the answer :wink:
[quote author="khstudio"]
Here is the (pre-made) power supply they use:
(I will be upgrading to a Linear PS)
http://www.ipdpower.com/catalog/product.asp?id=378 [/quote]
This supply is most probably SRW-45-2007, +18V/1,5A on output 1 and -18V/1A on output 2. Scrolling down the Application note mentioned a min load of 10% on output 1. (18V/150 ohm=120mA + load of the eq-circuit to archieve this min load of 150mA).
For your non switching power supply with regulators 7818/7918 or lm317/lm337 you don't need this resistor. It will only pull power and heat up your room. Just leave it out.
Your load caps 1000uF/35V will be fine. Rule of thumb was 1000uF per 1A load. This 5 OPamps will hardly draw that much current, so you're on the safe side.
khstudio
Well-known member
It's post like that, with complete answers, that help me really learn.
I'm starting to feel a piece of mind about this project now with most questions answered (except for the Filter Cap types):wink: & the test board complete, tested & sounding great as is.
Now that that resistor isn't needed the board can be cut down in size :green:
What needs to happen (for this cut down version at least) is for one of us to find a way to make the PCB drawing available outside of the software I created it in... but how :?: Some of you guy are on Macs & I'm not sure the software will work on them?
My session just got canceled so I'm going to refine all the files & parts list tonite.
O... anybody know what brand caps (BOX Type) are white with AV printed on the side???
Still would like to know CAP TYPES??? I'm ordering parts very soon & need to figure this out ??????:green:
Thanks, everybody
Kevin
I'm starting to feel a piece of mind about this project now with most questions answered (except for the Filter Cap types):wink: & the test board complete, tested & sounding great as is.
Now that that resistor isn't needed the board can be cut down in size :green:
What needs to happen (for this cut down version at least) is for one of us to find a way to make the PCB drawing available outside of the software I created it in... but how :?: Some of you guy are on Macs & I'm not sure the software will work on them?
My session just got canceled so I'm going to refine all the files & parts list tonite.
O... anybody know what brand caps (BOX Type) are white with AV printed on the side???
Still would like to know CAP TYPES??? I'm ordering parts very soon & need to figure this out ??????:green:
Thanks, everybody
Kevin
[quote author="khstudio"]
O... anybody know what brand caps (BOX Type) are white with AV printed on the side???
Still would like to know CAP TYPES??? I'm ordering parts very soon & need to figure this out ??????:green:
Thanks, everybody
Kevin[/quote]
I don't know what brand those caps can be :? but I'm pretty shure you'd be fine with a polyestercap like WIMA MKS2 1UF +/-10% 63V.
Polypropylene caps are said to have better highs and used in hi-fi stuff...
so for this application they might be the best. They're usually more expensive than polyester...
More on this in the Meta - forum
Check this out:
http://www.groupdiy.com/index.php?topic=2287
http://www.groupdiy.com/index.php?topic=7239
Just my 2 cent....
O... anybody know what brand caps (BOX Type) are white with AV printed on the side???
Still would like to know CAP TYPES??? I'm ordering parts very soon & need to figure this out ??????:green:
Thanks, everybody
Kevin[/quote]
I don't know what brand those caps can be :? but I'm pretty shure you'd be fine with a polyestercap like WIMA MKS2 1UF +/-10% 63V.
Polypropylene caps are said to have better highs and used in hi-fi stuff...
so for this application they might be the best. They're usually more expensive than polyester...
More on this in the Meta - forum
Check this out:
http://www.groupdiy.com/index.php?topic=2287
http://www.groupdiy.com/index.php?topic=7239
Just my 2 cent....
peterc
Well-known member
I think the sound of the circuit will dominate the sound of the individual components. The types of caps might make a difference, but I think that it will be minimal in comparison to the circuit topology.
The caps on the board look like bulk polys to me (could be polyprop, polyester/mylar or polycarb) but given the subtle nature of the cct, start with a Wima polyester, they are good caps.
Peter
The caps on the board look like bulk polys to me (could be polyprop, polyester/mylar or polycarb) but given the subtle nature of the cct, start with a Wima polyester, they are good caps.
Peter
mick
Well-known member
Hi Kevin I too would like to say a big thank you for all the work your putting into this project, and sorry that I'm of no help to you at this stage, can I just ask which brand of IC's you went with in the end.
Mick
Mick
Purusha
Well-known member
Or Polystyrene (Styroflex). M@anley uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.
khstudio
Well-known member
[quote author="Purusha"]Or Polystyrene (Styroflex). M@anley uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.[/quote]
WIMA can come in different flavors so...?
- But that is interesting... Styrene for the higher bands :idea:
They would be .47 (20k) & .22 (40k)
I'm GUESSING the originals are just Metalized Polyester... so I guess I'll find those in the WIMA's for my clones.
I'm getting some files ready for you right now :wink:
If it wasn't 10 damn degrees outside I'd be in the shop building
Kevin
I also put them in my Pultecs and they do sound more silky than the WIMAs.[/quote]
WIMA can come in different flavors so...?
- But that is interesting... Styrene for the higher bands :idea:
They would be .47 (20k) & .22 (40k)
I'm GUESSING the originals are just Metalized Polyester... so I guess I'll find those in the WIMA's for my clones.
I'm getting some files ready for you right now :wink:
If it wasn't 10 damn degrees outside I'd be in the shop building
Kevin
khstudio
Well-known member
x
khstudio
Well-known member
[quote author="peterc"]I think the sound of the circuit will dominate the sound of the individual components. The types of caps might make a difference, but I think that it will be minimal in comparison to the circuit topology.
The caps on the board look like bulk polys to me (could be polyprop, polyester/mylar or polycarb) but given the subtle nature of the cct, start with a Wima polyester, they are good caps.
Peter[/quote]
Actually the 1uf in mine are Panasonic "Stacked Metal Film"... not sure the film type http://dkc3.digikey.com/PDF/T071/P1377.pdf
I just had these in stock, they're surprisingly small :wink:
The new board is MUCH smaller 3.5 x 4.5. I was able to knock off an inch or so.
Kevin
The caps on the board look like bulk polys to me (could be polyprop, polyester/mylar or polycarb) but given the subtle nature of the cct, start with a Wima polyester, they are good caps.
Peter[/quote]
Actually the 1uf in mine are Panasonic "Stacked Metal Film"... not sure the film type http://dkc3.digikey.com/PDF/T071/P1377.pdf
I just had these in stock, they're surprisingly small :wink:
The new board is MUCH smaller 3.5 x 4.5. I was able to knock off an inch or so.
Kevin
Harpo
Well-known member
[quote author="Purusha"]Or Polystyrene (Styroflex). M@anley uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.[/quote]
Nothing wrong with styroflex, but pultecs are another circuit. Styroflex most often are in the pF range. For the 2.5kHz airband you need 4uF in this design. The largest styroflex I could find was 6.8nF, so you would need 588 caps in parallel to get 4uF. Lots of space and bucks for just 1 band (with all 5 airbands you have a total of 7.7uF).
I'd try the WIMA's (MKS-4-100) as peter_c suggested in a previous post. Maybe all a matter of taste, size and $.
Harpo
I also put them in my Pultecs and they do sound more silky than the WIMAs.[/quote]
Nothing wrong with styroflex, but pultecs are another circuit. Styroflex most often are in the pF range. For the 2.5kHz airband you need 4uF in this design. The largest styroflex I could find was 6.8nF, so you would need 588 caps in parallel to get 4uF. Lots of space and bucks for just 1 band (with all 5 airbands you have a total of 7.7uF).
I'd try the WIMA's (MKS-4-100) as peter_c suggested in a previous post. Maybe all a matter of taste, size and $.
Harpo
Purusha
Well-known member
Yes, good point Harpo.
Kevin, I am always re-drawing the layouts for home etching in Corel Draw.
Can you export your PCB layout in such a way one can see also the element
placement and their ID? I don't need the software layout. A simple PDF would be better for me.
Kevin, I am always re-drawing the layouts for home etching in Corel Draw.
Can you export your PCB layout in such a way one can see also the element
placement and their ID? I don't need the software layout. A simple PDF would be better for me.
khstudio
Well-known member
[quote author="Harpo"][quote author="Purusha"]Or Polystyrene (Styroflex). M@anley uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.[/quote]
Nothing wrong with styroflex, but pultecs are another circuit. Styroflex most often are in the pF range. For the 2.5kHz airband you need 4uF in this design. The largest styroflex I could find was 6.8nF, so you would need 588 caps in parallel to get 4uF. Lots of space and bucks for just 1 band (with all 5 airbands you have a total of 7.7uF).
I'd try the WIMA's (MKS-4-100) as peter_c suggested in a previous post. Maybe all a matter of taste, size and $.
Harpo[/quote]
Yea... forget the Styrene :thumb:
OK, I worked all night to get these files ready in a package for you guys.
I have compiled a master list of emails of all of you interested to send files to.
PM me to be added
ENJOY :green:
Kevin
I also put them in my Pultecs and they do sound more silky than the WIMAs.[/quote]
Nothing wrong with styroflex, but pultecs are another circuit. Styroflex most often are in the pF range. For the 2.5kHz airband you need 4uF in this design. The largest styroflex I could find was 6.8nF, so you would need 588 caps in parallel to get 4uF. Lots of space and bucks for just 1 band (with all 5 airbands you have a total of 7.7uF).
I'd try the WIMA's (MKS-4-100) as peter_c suggested in a previous post. Maybe all a matter of taste, size and $.
Harpo[/quote]
Yea... forget the Styrene :thumb:
OK, I worked all night to get these files ready in a package for you guys.
I have compiled a master list of emails of all of you interested to send files to.
PM me to be added
ENJOY :green:
Kevin
clintrubber
Well-known member
[quote author="khstudio"]
ENJOY :green:
Kevin[/quote]
:thumb:
BTW, these 'staggered' shelves remind me of the 'transparency'-mod for the SWR SM-400 bass amp. You got the normal bass & treble & four semi-param mid-bands. You could then add a 'second' treble-control set for another corner frequency. The topology used there (common topology, so also 'API-EQ alike') made it very easy to add bands: the transparency-mod was just another pot, one knob, one hole, one R, one C, some wire.
FWIW...
ENJOY :green:
Kevin[/quote]
:thumb:
BTW, these 'staggered' shelves remind me of the 'transparency'-mod for the SWR SM-400 bass amp. You got the normal bass & treble & four semi-param mid-bands. You could then add a 'second' treble-control set for another corner frequency. The topology used there (common topology, so also 'API-EQ alike') made it very easy to add bands: the transparency-mod was just another pot, one knob, one hole, one R, one C, some wire.
FWIW...
Purusha
Well-known member
Got the files. :grin:
Thanks again Kevin for doing this. :thumb: :thumb: :thumb:
My home studio gets better day by day with all this nice DIY projects.
Thanks again Kevin for doing this. :thumb: :thumb: :thumb:
My home studio gets better day by day with all this nice DIY projects.
khstudio
Well-known member
DON'T USE THE PCB FILE I SENT OUT!
I WILL RESEND IT>
I made changes that won't match the other files.
Hang on
kevin
I WILL RESEND IT>
I made changes that won't match the other files.
Hang on
kevin
My luck with making PCB's has been tragic, I'm hoping someone might be able to make a couple extra that I am so willing to pay for. I absolutley fell in love with this EQ from the first turn of the airband. If interested please PM me, I have PAYPAL!!!!
gar381
Well-known member
If someone is making PCBs for this project
I could use 2 channels worth as well. Please
let me know.
thanks
GARY
I could use 2 channels worth as well. Please
let me know.
thanks
GARY
jho-audio
Well-known member
me too.. thanks, jason
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