Eternity build - lower gain?

[DJPsychic]

Sorry to start another Eternity thread, but digging into this build

How can I lower the amount of gain, or at least widen the sweep?

Gain pot at "1" is already pretty saturated. This pedal would sound much better with the ability to boost at lower gain levels.

[idy]

That 1k attached to pin 2 and the 220n... raise it to 10k. Now minimum gain is around unity. If 5k, then minimum gain around 2....

[iainpunk]

That 1k attached to pin 2 and the 220n... raise it to 10k. Now minimum gain is around unity. If 5k, then minimum gain around 2....

he wants less gain, not more

raise the resistance of the 1k resistor that comes off of pin 2 to a higher value, i think starting with 10k would be alright, and go higher for less gain. the 220n cap that the other side of the resistor connects to should be made smaller at the same rate as well, to maintain the frequency response. resisor x10 means cap :10.

cheers

[DJPsychic]

Excellent, thank you so much! Will give that a try!

[Mark Hammer]

Getting ready for bed at the moment.  I'll give you a full response to Both threads tomorrow after breakfast.  Sleep tight.

[DJPsychic]

Getting ready for bed at the moment.  I'll give you a full response to Both threads tomorrow after breakfast.  Sleep tight.

Sounds good Mark,

I'll add "more volume" to my list of inquires...

I'm assuming lowering the 470R before "volume 1" wire  would give me more output?

To recap: I'm looking for More volume, less gain (or at least wider sweep), and functioning treble pot.

(Pretty standard diystompbox tone quest lol)

[Mark Hammer]

Okay, this is the schematic I'm working from.  I am assuming it is accurate.  If it isn't, my bad, and please ignore.



I assume you are working from this stripboard layout.  http://tagboardeffects.blogspot.com/2012/02/lovepedal-eternity.html

Right away, I see that the tagboard layout indicates a 2+1 diode complement, while the schematic I posted here is a 2+2, making it more like a Timmy.  That 2+2 arrangement, however, will yield a slightly louder maximum output, by raising the clipping threshold for both halves of the waveform, rather than just the one.  It will also reduce how intense the clipping can get.

The schematic I show uses a 100nf cap on the ground leg of the clipping stage while the tagboard one uses 220nf.  A 100nf cap provides bass rolloff starting around 480hz, while 220nf, in tandem with 1k, rolls off starting around 720hz.  Since bass content is usually higher amplitude, moving the rolloff downward results in a bit more clipping.  A TS-9 rolls bass off around 720hz, so 480hz provides a little more meat.  I did a similar mod to a buddy's TS-9 and he likes it.  Your choice.

A smoother tone will be achieved by putting a smallish cap in the feedback loop of the clipping stage; e.g., 68pf.  A TS-9 uses 51pf, but I think we can move the treble rolloff down a little.  Note that it really only has impact as the gain control gets set to max or near.  Below that, the impact on treble content is negligible.

A TS-9 will use 1k/220nf on the output of the clipping stage, while this one uses 1k/150nf.  A 150nf value provides a treble rolloff around 1060hz, while 220nf starts around 720hz.  This is partly why I suggest the 68pf feedback cap - to compensate for what the 150nf doesn't do.  As well, the Eternity Tone control uses a 330R resistance to ground, while a TS-9 uses 220R.  The difference is not huge, but it does mean that, when you combine that with the use of 150nf on the output of the clipping stage, and the lack of feedback cap, there's a lot of treble that's NOT being rolled off.

The circuit actually doesn't aim for much gain.  At least the one I show.  By my calculations, the schematic I show has a max gain of 158x, while the tagboard layout provides for a max gain of of around 520x.  So, using 3k3, like the schematic I show, moves you in the direction of less gain, and presumably a less twitchy gain control.  Along with the 2+2 diodes, that should get you a milder drive with plenty of volume on tap.

[DJPsychic]

Thank you mark!

Lots of great info I appreciate it.

I believe the schematic you posted might be closer to the Eternity "Burst" version? Except I don't see the 2k2 so maybe not. (Lots of versions hard to keep track)



I actually like the way my build sounds overall, just wish I could have some more headroom. And like I said the gain is pretty saturated very early in the pots rotation. Will have dig into the mods you suggest.

Not to totally back track on every thing you just explained, but is there a way to achieve a bit more volume on my original layout, without the 4x diodes configuration?

[DJPsychic]

Here's another schematic I found

[iainpunk]

replace the diodes with red LED"s

it will increase headroom and volume. the perceived gain will be about half, and the volume would be just under twice as much.

cheers

[DJPsychic]

Here's a clip of my lowered gain TS/Eternity/SoS thingy. Recorded on handheld ZOOM recorder. It's set up across the room from amp.

https://soundcloud.com/user-809000973/od1?si=a9ecf6a5d78142c7ab7f0192b4a587f3

Not the best quality. Playing is terrible as well lol - but I think you'll get what I'm after. Boost, transparency, a little warmth.

Fender Strat neck PU > Fender Blues Deluxe

I swapped the 3k3/100nf as suggested by @mark
Increased input cap to 100nf as well

Settings on the pedal (1-10)

VOL - 9 (almost dimed)
GAIN - 4ish
TONE - 0  - almost unusable. Still need to do more digging on this via the links provided by @druid and others. Might just delete.

Tempted to leave as is, but would like to work on the output level, even if it's for aesthetic purposes. Not keen on having a pedal I need to have VOL maxed and TONE at 0 to be usuable.

[DJPsychic]

replace the diodes with red LED"s

it will increase headroom and volume. the perceived gain will be about half, and the volume would be just under twice as much.

cheers

Definitely an interesting idea, thank you!

I'm afraid the LED's might change the sound too much. Really happy with what I have dialed in, just needs more headroom on the VOL pot.

[iainpunk]

i suggest putting in sockets so you can experiment with diodes
some pairs will sound different shades of different and every pair will have a slightly different volume. the tonal difference probably won't be as different as some people on the www would have you believe.

cheers