EHX - Low Frequency Compressor [schematic]
- gigelmargel
- Resistor Ronker
Any chance for a PCB?
I am very curious how it sounds
Thxa all for your work!
I am very curious how it sounds
Thxa all for your work!
- gigelmargel
- Resistor Ronker
No news?
- mictester
- Old Solderhand
Information
The use of the OTA in the feedback loop actually improves the S/N and bandwidth of the op-amp as the attenuation is increased, because you're increasing the negative feedback! It's quite a good approach to a voltage (or current) controlled amplifier, but has a few problems - limited range of control, small range of input voltages before it runs into distortion, and so on.PierreBPSFSB wrote: - BlackFinger: also, following the post, i have seen the Morley (ProComp PCBmod), and it has the same clever use of OTA (attenuation inside the feedback loop, to keep the S/N # constant), but the CA3080 both inputs was "grounded": here the input are signal feeded, so it is more a signal "negative feedback" (with careful phase e- pin2 on µA741) than an output variable conductance.
It is just a remark
"Why is it humming?" "Because it doesn't know the words!"
- gigelmargel
- Resistor Ronker
Anyone has a PCB for this compressor?
- seedseed
- Breadboard Brother
Is there a vero layout somewhere for this one? I think it would work fine with a lm13700 also just use half the ic or make a blackfinger and a low frequency compressor with one ic on the same board would be cool also. Depends how keen you are on this pedal i guess. What is the software called that everyone makes the vero designs on and where can i get it? i usually do mine on paper and pencil but a program would be good also. Thanks
- pedalgrinder
- Cap Cooler
Hi everyone,
I am new to this whats the easiest way of cloning a pcb picture. do you invert the picture or is there software you can use. obviously there would be a few of you guys who have done this. I was trying to save myself some pain and learn the easy way of doing it through someone else's experience. Thanks any advice would be much appreciated.
I am new to this whats the easiest way of cloning a pcb picture. do you invert the picture or is there software you can use. obviously there would be a few of you guys who have done this. I was trying to save myself some pain and learn the easy way of doing it through someone else's experience. Thanks any advice would be much appreciated.
What's the best thing about fat chicks and scooters? There both fun to ride around until your mates find out!
- JiM
- Diode Debunker
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Do you want to etch a PCB, or to draw a layout ?pedalgrinder wrote:Hi everyone,
I am new to this whats the easiest way of cloning a pcb picture. do you invert the picture or is there software you can use. obviously there would be a few of you guys who have done this. I was trying to save myself some pain and learn the easy way of doing it through someone else's experience. Thanks any advice would be much appreciated.
You may want to look into those forum subsections :
https://www.freestompboxes.org/viewforum.php?f=45
https://www.freestompboxes.org/viewforum.php?f=51
https://www.freestompboxes.org/viewforum.php?f=21
Your questions are very likely to be answered there already. And don't forget to use the search feature!
I only give negative feedback.
- Scruffie
- Opamp Operator
Alot of people (my self included) use DIY Layoutcreator for Vero layouts, there are a few other options but i'm not sure what there names are.seedseed wrote:Is there a vero layout somewhere for this one? I think it would work fine with a lm13700 also just use half the ic or make a blackfinger and a low frequency compressor with one ic on the same board would be cool also. Depends how keen you are on this pedal i guess. What is the software called that everyone makes the vero designs on and where can i get it? i usually do mine on paper and pencil but a program would be good also. Thanks
It probably will work with an LM13X00, it might need an adjustment or two though... i'd be more interested in getting it to run off a single supply or atleast adding a charge pump on board if you want the extra headroom.
- phibes
- Transistor Tuner
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I use to redraw them into Illustrator but shit, that would take all day. Just download ExpressPCB and redraw it in there. You can adjust lead spacings and what not in the program so you can end up with a pretty close layout. I also like ExpressPCB for exporting the file as a vector image for printing. Better traces and pads. I know I should learn eagle but I've really never been let down with ExpressPCB. Once you fuck around with it enough it becomes second nature.pedalgrinder wrote:Hi everyone,
I am new to this whats the easiest way of cloning a pcb picture. do you invert the picture or is there software you can use. obviously there would be a few of you guys who have done this. I was trying to save myself some pain and learn the easy way of doing it through someone else's experience. Thanks any advice would be much appreciated.
This would be a fun one to convert to single power supply though. Everybody and their brother has built a Ross and Dyna already.
Mictester, anything you'd improve on the design?
GuitarlCarl - "TGP = The Gear Polishers"
Ken
Ken
- pedalgrinder
- Cap Cooler
Does anyone know in this compressor which resistor or capacitor's in the the first low frequency compressor where it's using the transistor as the attenuator which resistor or capacitor would be the time constant's for the attack and release??? It would be good candidate for playing with these particular options. Cheers
What's the best thing about fat chicks and scooters? There both fun to ride around until your mates find out!
- seedseed
- Breadboard Brother
i'd love to build one of these also. has anyone done one. Would be good for a nice vintage sound. I would think it would clip a bit using a transistor as the attenuation method. But thats not always a bad thing anyone cloned one??????
- phibes
- Transistor Tuner
Information
I think there's a layout in this thread. The Black Finger is the same as the LFC from what I remember. Try er out.
https://www.diystompboxes.com/smfforum/ ... ic=25952.0
I don't think anyone has ever really dived into due to the power supply. A bipolar power supply can easily be integrated.
https://www.diystompboxes.com/smfforum/ ... ic=25952.0
I don't think anyone has ever really dived into due to the power supply. A bipolar power supply can easily be integrated.
GuitarlCarl - "TGP = The Gear Polishers"
Ken
Ken
- pedalgrinder
- Cap Cooler
Here we go threadjacked hahhaha
What's the best thing about fat chicks and scooters? There both fun to ride around until your mates find out!
- pedalgrinder
- Cap Cooler
is there any track side pics of the low frequency compressor using transistor attenuation rather than the ota. The schematic is there but has anyone got some gust shots of that particlular one especially the track side. I reckon the transistor one would sound better than the ota one. Cheers
What's the best thing about fat chicks and scooters? There both fun to ride around until your mates find out!
- mictester
- Old Solderhand
Information
I can assure you that it doesn't! The transistor attenuator introduces a lot of distortion, and completely destroys any dynamics that the guitar has!pedalgrinder wrote:is there any track side pics of the low frequency compressor using transistor attenuation rather than the ota. The schematic is there but has anyone got some gust shots of that particlular one especially the track side. I reckon the transistor one would sound better than the ota one. Cheers
The 3080 version is MUCH better and has a better frequency response and lower distortion than the MXR. The minor problem of dual rail operation shouldn't really put you off!
"Why is it humming?" "Because it doesn't know the words!"
- pedalgrinder
- Cap Cooler
it's not that at all dual power supply i prefer. i disagree with you i think it sounds better on a bass maybe a guitar you may find that but for a bass the transistor would give better attenuation sound even with the bit of distortion than the hissing ota. I can't say iam a big fan of transconductance amplifier compressor they just don't do it for me. So if anyone has a track side to the transistor version i would love to see it. Cheers
What's the best thing about fat chicks and scooters? There both fun to ride around until your mates find out!
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- Posts: 2
- Joined: 05 Jun 2013, 22:45
Hi,
Thank you very much for your schematic, this is a good work.
But, I don't understand, were are the tubes on the scheme? I thought that this model is a tube compressor and that's what I am searching.
Regards,
Alex.
Thank you very much for your schematic, this is a good work.
But, I don't understand, were are the tubes on the scheme? I thought that this model is a tube compressor and that's what I am searching.
Regards,
Alex.
Information
- Posts: 2
- Joined: 05 Jun 2013, 22:45