NPD - Morley PFL pro flanger

[lars]

I recently was able to get a 1978-79 Morley PFL flanger, and I can tell you, these things may be the best modulation pedal ever made...once you get them adjusted correctly.
I figure to lead off with the good stuff, an inside shot:

Thankfully, the SAD1024 was intact and working perfectly. Huge sigh of relief when I opened it up!
Here's the outside. It doesn't look too bad for being 40+ years old:

Now the part that can be scary at first. When I first powered it up, it worked, but it didn't sound good at all. It was nothing like the one Andy Martin demos in his youtube video. Mine didn't do any kind of oscillation. The flanging was shallow and lifeless.
I'm sure you noticed all the trimpots all over this thing. That's the key. Somebody had really messed this thing up at some point. The 100k and 25k pots in the upper left control the low and high limits respectively. The 100k pot was adjusted so there was no bottom end in the sound. Once I adjusted that...boom, there was that thick/syrupy/watery flange that really only an SAD1024 can produce. I've never owned an SAD1024-based pedal, but there is definitely some special mojo in that chip. The 25k "high limit" pot can be adjusted to taste, but that 100k "low limit" pot is critical to the overall sound. The other thing to mention here:  this thing is quiet! How is that possible? The SAD1024 is supposed to be a noisy beast. Credit Ray Lubow for designing an excellent circuit here. It's more quiet than any BBD-based effect I've ever used. Very, very minimal hiss and absolutely zero clock noise of any kind even at the most extreme settings. And no 60-cycle hum despite the fact there are TWO AC transformers in there. Amazing design.
Next was the 25k pot located pretty much dead center in the board. That controls the harmonic emphasis (feedback). It was adjusted way too low, so no oscillation was possible even at the max setting on the outside control. A bit of clockwise turning and I was right in that crazy oscillation territory that can then be controlled with the foot control. It's great.
Some of the sounds these can create are not for everyone. The physical size of this beast certainly does you no favors on pedalboard space either. But if you like being able to push modulation to it's limits with that classic 70's flanger sound, there is hardly another pedal-format flanger that can beat these.

[matmosphere]

Very nice... I think we're gonna need some audio clips

[Scruffie]

Ah! You signed up in the end.

It actually shares a lot in common with the A/DA flanger in design, seemingly too much to be a coincidence but different enough that it's definitely not a copy...

Did you take a reading of the actual clock frequencies?

[gordo]

I'm SO jealous. 

[lars]

Ah! You signed up in the end.

Actually, I had found this one and bought it before I saw that JLA one. I wasn't even looking for one of these and just stumbled onto it, saw the price, and said "yes, please". That being said, that other JLA one is still available, and it's definitely worth it.

Did you take a reading of the actual clock frequencies?

I have no way to do that (I wish I had the equipment and know how to do real tuning). I'm sure this thing could be dialed in even better, but I'm really liking where it's at right now. It can even do some "through zero" sounds when you run heavy distortion through it. The SAD1024 seems to be run in a unique way in this circuit compared to the A/DA or the 18v Electric Mistress. All the outputs are run in parallel (pins 5,6,11,12), instead of just using 5 & 12. Maybe that's what takes the Morley over the top?

[Scruffie]

I have no way to do that (I wish I had the equipment and know how to do real tuning). I'm sure this thing could be dialed in even better, but I'm really liking where it's at right now. It can even do some "through zero" sounds when you run heavy distortion through it.

It was less about the set up (although you might find you're able to squeeze a bit more out of it) more tells us about the actual circuit and the sound you're getting. The A/DA also does those 'through zero' tones because of how big the sweep is and how short the delay can get. A cheap VC97 multimeter will let you take clock readings.

The SAD1024 seems to be run in a unique way in this circuit compared to the A/DA or the 18v Electric Mistress. All the outputs are run in parallel (pins 5,6,11,12), instead of just using 5 & 12. Maybe that's what takes the Morley over the top?

Nothing magic in it, instead of improving the sampling rate it's improving the S/N.

[lars]

A cheap VC97 multimeter will let you take clock readings.

Thanks for the heads up. The VC97 looks like a great candidate to give me some more features, although I really should invest in some kind of scope. It would be nice to have some precision instead of always tuning by ear. It's also invaluable for troubleshooting. I've seen many an Uncle Doug video where his scope pinpoints issues that otherwise could be hours of headaches.

Nothing magic in it, instead of improving the sampling rate it's improving the S/N.

Ah, now that makes sense as to why this thing doesn't seem to be as noisy as I would expect.

[diablochris6]

That's a nice looking piece of equipment, especially for its age. Nice find!

[danfrank]

Necropost!! Lol!
I was given one of these to repair a while ago, I finally got it working the way it should be. This thing had problems!
First, it had to be converted from 240 volts in to 120. Bang, 2 new transformers right there. Someone had put in a 4047 where a 4007 should be, either the guy who had this before had bad eyesight or had no idea what was going on.
The "sockets" used for the BBD and CMOS ICs stink, so those were changed out along with a faulty LM324, so that got a socket too.
Bad electrolytic caps were changed out. I replaced a lot of 1uf electros for mylar.
Two trimmers were making intermittent contact, so those were changed also.

I never worked on one of these chrome Morleys before, they're kind of neat in their ingenuity. They use a small piece of black tolex to cover the photoresistors when the foot pedal is used!
This circuit is very similar to the old A/DA flanger circuit, but just a little bit different.
By the way, clock speeds go from 20kHz to 800 kHz, a 40 to 1 sweep ratio like the old A/DA. The clock can be adjusted to much faster but the flange effect really goes away any faster than 800kHz. Anything below 20kHz and it gets too noisy.