LM308 and OP07 - the plot thickens

Youtube demos are great - except for evaluating a tone.

Actually a while ago a friend came around to listen to two pedals I had built. As I played them the differences were night and day. So I got him to play and I couldn't hear any difference at all. He was playing and saying things like man they are so different! When I played he couldn't hear a difference and when he played I couldn't. But as the player it was apparently apparent! I guess it was how they reacted to playing which was the key.

Sometimes I doubt my sanity with this hobby.
 
Thats a thing for real! Some years ago some vintage guitar guys met and brought their vintage guitars. There was also a blind comparism held between vintage and replicas. A famous player hid behind a wall and played them randomly. The listeners had to guess. The results were not more than slightly above random results. But the player was sure he always heard a clear difference.
 
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Youtube demos are great - except for evaluating a tone.

Actually a while ago a friend came around to listen to two pedals I had built. As I played them the differences were night and day. So I got him to play and I couldn't hear any difference at all. He was playing and saying things like man they are so different! When I played he couldn't hear a difference and when he played I couldn't. But as the player it was apparently apparent! I guess it was how they reacted to playing which was the key.

Sometimes I doubt my sanity with this hobby.

I remember noticing something similar to this back in college. One my my roommates got a pod XT and when he played it, I thought it sounded really good. Then I tried and it felt and sounded weird, kind of had a ‘rubber band’ feeling, which later I realised was a bit of perceptible latency with the pod XT.

More recently I remember recording an on/off clip of an overdrive pedal into a high gain amp, when playing it was night-and-day, much more saturation and attack with the pedal on. In the recording? Hardly noticeable difference.

recordings tell less than half the story, all ‘x doesn’t make a difference!’ YouTube influencer videos are a grift and they know it.
 
Feel is something that YouTube demos obviously cannot convey. And while I don't want to belittle anyone and it sounds super corksniffy, not everybody has good ears for guitar tone. Some don't even care about different types of distortion, they will just play the exact same whether it's through a Muff, Rat, HM-2, Mesa Dual Rectifier, Line 6 Insane channel or Marshall fridge.

That being said, the LM308 is the "correct" chip for a Rat just like the JRC4558DD is the "correct" one for the TS. The circuits were constructed with these first and foremost and that's why they usually just sound right. Although as we know preferences can vary...
 
Youtube demos are great - except for evaluating a tone.

Actually a while ago a friend came around to listen to two pedals I had built. As I played them the differences were night and day. So I got him to play and I couldn't hear any difference at all. He was playing and saying things like man they are so different! When I played he couldn't hear a difference and when he played I couldn't. But as the player it was apparently apparent! I guess it was how they reacted to playing which was the key.

Sometimes I doubt my sanity with this hobby.
Quantum guitar playing. The observation (and the playing) affects the sound of the instrument or pedal. Real phenomenon, I swear!
 
Done and the results are... interesting. I've been using the pedal a bit with the OP07 in it so I'd be familiar enough to notice a change.

Did it change (EDIT: when I installed the LM308)? I believe so. With the distortion pot between about 10% and 30%, it's a lot more usable. It's still not an overdrive, it sounds pretty Ratty until there's zero gain and the sound drops out, but at lower gain settings it's a cleaner Rat with a bit more definition. Which is a good result, I'd say. Worth the cost? I'd say so, it makes the pedal a bit more versatile.

I tried measuring it as Chuck suggested, but it read around 100µA, so either I did it wrong or my DMM is not that sensitive. Probably the second one, it's a cheapy, though it does work well for my needs and seems pretty accurate at other tasks.

EDIT: Tried the pedal with different guitars, and it really does seem to sound nicer all through the range of the Dist knob. It's less obvious with higher gain but I do think I can hear a subtle difference there too.
 

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Done and the results are... interesting. I've been using the pedal a bit with the OP07 in it so I'd be familiar enough to notice a change.

Did it change? I believe so. With the distortion pot between about 10% and 30%, it's a lot more usable. It's still not an overdrive, it sounds pretty Ratty until there's zero gain and the sound drops out, but at lower gain settings it's a cleaner Rat with a bit more definition. Which is a good result, I'd say. Worth the cost? I'd say so, it makes the pedal a bit more versatile.

I tried measuring it as Chuck suggested, but it read around 100µA, so either I did it wrong or my DMM is not that sensitive. Probably the second one, it's a cheapy, though it does work well for my needs and seems pretty accurate at other tasks.

EDIT: Tried the pedal with different guitars, and it really does seem to sound nicer all through the range of the Dist knob. It's less obvious with higher gain but I do think I can hear a subtle difference there too.
💯
 
Done and the results are... interesting. I've been using the pedal a bit with the OP07 in it so I'd be familiar enough to notice a change.

Did it change? I believe so. With the distortion pot between about 10% and 30%, it's a lot more usable. It's still not an overdrive, it sounds pretty Ratty until there's zero gain and the sound drops out, but at lower gain settings it's a cleaner Rat with a bit more definition. Which is a good result, I'd say. Worth the cost? I'd say so, it makes the pedal a bit more versatile.

I tried measuring it as Chuck suggested, but it read around 100µA, so either I did it wrong or my DMM is not that sensitive. Probably the second one, it's a cheapy, though it does work well for my needs and seems pretty accurate at other tasks.

EDIT: Tried the pedal with different guitars, and it really does seem to sound nicer all through the range of the Dist knob. It's less obvious with higher gain but I do think I can hear a subtle difference there too.

The way your post is worded, you're saying the OP07 is a "lot more usable", "it's a cleaner Rat" etc.
It's not until the "Worth the cost?" comment that I'm lead to believe maybe you're talking about the LM308. (maybe "LM308H")

And then I saw the picture... 😹
 
The way your post is worded, you're saying the OP07 is a "lot more usable", "it's a cleaner Rat" etc.
It's not until the "Worth the cost?" comment that I'm lead to believe maybe you're talking about the LM308. (maybe "LM308H")

And then I saw the picture... 😹
I was referring to my earlier post in this thread, on the previous page. But fair enough, it wasn't obvious.
 
The metal can LM308Hs I had were/are horrible, way too fuzzy and messy. Plastik ones I like better usually but there are way too many fake ones.
 
The metal can LM308Hs I had were/are horrible, way too fuzzy and messy. Plastik ones I like better usually but there are way too many fake ones.
Maybe the metal can ones were fake.

There's a quick & easy test to see if an LM308 is legit. It's close to 100% accurate at spotting fakes. Measure the DC current flowing into pin 7. Should be around 250μA. Most opamps are over 1mA.
 
The most noticeable difference between LM308 and other opamps is the note decay when DIST is above noon. To my ears anyway. It's one of those things that once you hear it, you can't unhear it. My hearing is not great. They say hearing is the 1st thing to go and I forget what the 2nd one is.

Plastic & metal can LM308's should sound the same because it's the same die inside. Metal cans have Mojo, or so they say.

black cat bone 03.jpg
 
Youtube demos are great - except for evaluating a tone.

Actually a while ago a friend came around to listen to two pedals I had built. As I played them the differences were night and day. So I got him to play and I couldn't hear any difference at all. He was playing and saying things like man they are so different! When I played he couldn't hear a difference and when he played I couldn't. But as the player it was apparently apparent! I guess it was how they reacted to playing which was the key.

Sometimes I doubt my sanity with this hobby.
This is exactly how I feel about gear in general! I can only trust myself to decide how something sounds. The player is a huge variable and the way the guitar responds under the fingers is often the biggest factor for me.
 
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