Rothwell - Love Squeeze Compressor

WhiteKeyHole · Post by **WhiteKeyHole** » 20 Mar 2011, 13:39

Yes, I have built it using the layout I posted. Worked just like the original. The unit I traced from did distort a bit at higher compression settings but nothing crazy. You must have made a mistake somewhere.

Ripdivot · Post by **Ripdivot** » 20 Mar 2011, 19:28

OK thanks, I'll double check my connections again. Do you think the slightly different fet and op-amp have anything to do with the problem? What diodes did you use?

WhiteKeyHole · Post by **WhiteKeyHole** » 20 Mar 2011, 19:48

No, they shouldn't cause any problem. I used 1N5818 but any low Vf diode will produce similar results.

Check the rectifier, the distortion is probably a result of no action at the FET VCR.

WhiteKeyHole · Post by **WhiteKeyHole** » 20 Mar 2011, 19:50

improper action*

Magnus290 · Post by **Magnus290** » 21 Mar 2011, 06:38

Hi Whitekeyhole!

You mentioned something about wrong values for som caps and a missing connection. Is this fixed on the schematic and your layout???

Im Planning to build this compressor because I have heard from a friend that i sounds good. Would be nice to know if its working as it is or if I have to try out some values.

Regards Magnus

WhiteKeyHole · Post by **WhiteKeyHole** » 21 Mar 2011, 12:46

Yes, the connection is fixed on both. Many of the cap values are unknown -- unit wasn't mine so I didn't remove them for measuring.

As I said, C12 is not 10nF. I just left it out. Based on the feel of the compressor and its response to low notes, C3 may be 1nF. C1 is any value allowing full-range. C2, 100pF would work.

mictester · Post by **mictester** » 21 Mar 2011, 13:17

Ripdivot wrote:I bread boarded this pedal tonight but I thought it sounded more like a crappy overdrive than a compressor. I didn't have the "1n5817" diodes so I tried Bat41's, 1n4148"s and germanium. I also didn't have a 2n5457 fet with the "T" designation, mine just says "2n5457". I'm not sure if these changes would make the pedal not function properly. I found that it really distorts when you turn the compression up which makes sense with the LED's in the feedback loop so I remove them and it still distorted. I really wasn't hearing a whole lot of compression. Also my op-amp is a TLO72CP not a TLO72P as shown in the schematic. Has anyone else built this with any success?

A few minutes with a search engine would answer your questions!

The 1N5817 diodes are ordinary Schottky types, though you could use almost anything else if you could accept different a onset of compression. There's nothing magic about the part (and they're not in the signal path).

The 5457 has a fairly wide range of specification (though smaller than some of the cheaper FETs). The "T" doesn't really matter. Just be certain what ever FET you use is connected the right way 'round (even a 2N3819 would work).

The TL072 CP and P versions are identical for our purposes. You could use an LF353 (for example) and get exactly the same results.

There is no reason to ever get hung up about using exactly the same components as an original. A Tubescreamer (for example) will give the same results (with differing amounts of hiss) with ANY dual op-amp. Learn to read and understand the data sheets, and you'll save time, money and frustration by understanding how you can substitute parts!!

Ripdivot · Post by **Ripdivot** » 22 Mar 2011, 06:32

OK so I got it working...I had forgot the ground connection on the pos side of C10. So I like it at the lower compression settings but as I have read elsewhere it distorts at higher compression settings even if you remove the LEDs. Depending how you want to use it this could be a good thing. I have tried several types of diodes in the rectifier circuit that controls Q1 and didn't notice a whole lot of difference between them. It is quite transparant as you can't really notice it is on until you shut it off. I have a Flatline Compressor as well and at the end of the day I think I like the Flatline better because it is cleaner at the higher compression settings. At lower settings they are pretty even.

kbibs · Post by **kbibs** » 01 Apr 2011, 00:58

I was just wondering if there was any update to the cap values for this? I'm thinking of breadboarding it.

Thanks!

WhiteKeyHole · Post by **WhiteKeyHole** » 01 Apr 2011, 01:08

Why not experiment until you find something you like? I already gave informed suggestions about what the values may be, start from there.

kbibs · Post by **kbibs** » 01 Apr 2011, 11:24

That's what I plan on doing, I was just curious.

Thanks for all the upfront work on this!

WhiteKeyHole · Post by **WhiteKeyHole** » 04 Apr 2011, 07:58

Updated: Removed incorrect value for C12. Schottky diodes now show true part (SOT-23 package). No circuit/structural changes.

WhiteKeyHole · Post by **WhiteKeyHole** » 04 Apr 2011, 08:00

Please merge.

seedseed · Post by **seedseed** » 04 Apr 2011, 08:21

great job but i can't spot the new values on those caps on the schematic unless iam not looking in the correct spot

WhiteKeyHole · Post by **WhiteKeyHole** » 04 Apr 2011, 08:36

C12 was notated with an incorrect value, there is no new value to replace that incorrect value.

The only unknown value where specificity is of any great importance is C3. This will affect the action/onset of compression relative to the frequency of the note(s) played. I suppose this value to be 1nF as a result of playing guitar through the unit and making note of where (on the neck) the compression became evident.

Alternatively, C3 can be made any value allowing for full-range and the value of C7 can be altered to the same end.

guycapuano · Post by **guycapuano** » 01 Sep 2011, 20:14

WhiteKeyHole wrote:600 DPI

this is excellent, thanks, is there are parts list?

guycapuano · Post by **guycapuano** » 02 Sep 2011, 14:53

Nevermind, I see the schematic

Anyone ever confirm the unknown values of C12 and c3?

guycapuano · Post by **guycapuano** » 03 Sep 2011, 03:38

just released I need to manually check the notify box

must be new

engineelite · Post by **engineelite** » 05 Sep 2011, 17:30

I've got the real Rothwell Love Squeeze and it doesn't distort even with the compression maxed. I'm running a tele with the CS no caster pickups in it. I'd love to be able to clone the love squeeze and put it in a multi-circuited box with overdrive and reverb but if the clone is distorting then I guess I'll wait until that is sorted out. Keep up the good work guys!

WhiteKeyHole · Post by **WhiteKeyHole** » 05 Sep 2011, 17:48

There's nothing to sort out. The distortion was observed while using the real Rothwell Love Squeeze that the schematic was traced from. Your pedal may be a newer revision having changes to reduce/eliminate that distortion.

Post pictures and we'll find out.

Rothwell - Love Squeeze Compressor [traced]