DEMO Magnetron Delay (Keeley Magnetic Echo)

This post contains an audio or video demo
owlexifry

owlexifry

Well-known member
Build Rating
5.00 star(s)
Always liked the mad prof deep blue delay (seabed delay), it’s been on my board since i built it.

until today.

IMG_2577.jpeg

hot damn, the added modulation controls just makes this a clear step above a three-knobber.
yeah its still got the lofi qualities of the PT2399, but tbh i love how this sounds for such an easy and economical build.
should’ve tried this one sooner tbh.
highly recommend.

IMG_2574.jpeg


IMG_2581.jpeg

One thing I would criticize, it's definitely no issue, but it feels like the modulation depth control (linear) doesn't really do much until 2o'clock or more. maybe that's intended to bring in a very subtle amount at a lower intensity (depth) range, but in the higher intensity range it feels like there's comparably less travel. or maybe im just a modulation fiend.
 
I like the disaster transport a lot, out of the pt2399 stuff, because the modulation on the tails can be on a switch and you can adjust the rate and depth, it can get pretty spooky if you want. And pt2399 delays are fun to put an adjustable momentary feed back mod on,
 
jjjimi84 said:
Looks great and love the demo! The sea machine is a good bag of weird
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useable weird? or just fun weird? I enjoy a bit of chorus, even for some high gain clown behaviour

Paradox916 said:
I like the disaster transport a lot, out of the pt2399 stuff, because the modulation on the tails can be on a switch and you can adjust the rate and depth, it can get pretty spooky if you want. And pt2399 delays are fun to put an adjustable momentary feed back mod on,
Click to expand...
had a look but it appears only 4-knob Jr version PCB available (cataclysm delay) but the full size 6-knob one looks awesome
 
owlexifry said:
useable weird? or just fun weird? I enjoy a bit of chorus, even for some high gain clown behaviour


had a look but it appears only 4-knob Jr version PCB available (cataclysm delay) but the full size 6-knob one looks awesome
Click to expand...
You could probably mod the cataclysm but effects layout gatekeeper is the Disaster Transport
 
owlexifry said:
cheers \m/

what else is good for a PT2399?

these are looking pretty tempting..
www.pedalpcb.com

Pitch Witch - PedalPCB.com

Compare to MidFi Pitch Pirate Deluxe
www.pedalpcb.com www.pedalpcb.com
www.pedalpcb.com

Sea Horse - PedalPCB.com

Compare to EQD Sea Machine
www.pedalpcb.com www.pedalpcb.com
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I don't know about the Seahorse, but the Pitch Witch is all kinds of weird too. It's fun one, but I'd call it more of a special effects pedal. It does give you the ability to blend in your dry signal, so you can use it subtly, but I don't feel like it wants to be played that way.
 
i love my magnetron, one of my favorites so far. the modulation sounds awesome, it really does feel like a proper tape warble (to the degree that it can).

love the enclosure and thanks for a great demo!
 
jjjimi84 said:
A little bit of a and a lotta bit of b.
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chris.knudson said:
I don't know about the Seahorse, but the Pitch Witch is all kinds of weird too. It's fun one, but I'd call it more of a special effects pedal. It does give you the ability to blend in your dry signal, so you can use it subtly, but I don't feel like it wants to be played that way.
Click to expand...

on second thought, perhaps these are not for me 😅
1710896667979.png

airbud said:
i love my magnetron, one of my favorites so far. the modulation sounds awesome, it really does feel like a proper tape warble (to the degree that it can).

love the enclosure and thanks for a great demo!
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heck yeah, im all about that modulation!
thanks - tayda matte army green is always a win
 
airbud said:
the enclosures are what interests me least about the whole thing.
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I get it man -- It's stressful enough plugging it in and praying it works -- but before you can even do that you gotta make it pretty. I must have 6 or 8 completed boards on my bench waiting for graphics and an enclosure.
 
airbud said:
ah i might try tayda then! i've been drilling my own from bare aluminum and just recently spray painted a few gold, but the enclosures are what interests me least about the whole thing.
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same. tayda is a godsend for me. i hate painting. fumes, mess, and bs aside, i'm just not good at it.
powdercoating is superior, and an enclosure from tayda costs less than literally anywhere else in the world. it's a no brainer.
 
Cracking demo!

I love mine and I also noticed the Modulation knob doesn't do much until the end of the sweep.

I try not to use delay. When I do it's slapback with a bit of warble.

Is there a way to mod the circuit to reduce the delay time so it becomes a chorus?
 
Lorence_Customs said:
What value do you set the Trim Pot to? Do you set it in the middle and adjust to sound?
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I would adjust to sound. It's for the gain of the signal going into the input--too low and your dry and repeats will sound quieter than your bypass. You can boost the signal if you want it to jump up a bit when you turn it on, but too high and it might distort the delay, so I try to get a unity between bypass and effect.
 
Lorence_Customs said:
What value do you set the Trim Pot to? Do you set it in the middle and adjust to sound?
Click to expand...
yep. pretty much exactly what @spi said.

andare said:
Cracking demo!

I love mine and I also noticed the Modulation knob doesn't do much until the end of the sweep.
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cheers 🤙🏻
yeah it’s weird, i don’t understand why it’s that weak, when compared to the dark rift where the modulations on that are wild and awesome but very controllable.

andare said:
Is there a way to mod the circuit to reduce the delay time so it becomes a chorus?
Click to expand...
probably, i wouldn't know though.

Alright, well since this build report got bumped, I have an update to provide regarding FAKE OPAMPS.

So when i was testing out the FX loop in the recently finished xenotron, i thought i'd try this magnetron in there.
well, HOLY CRAP, check out this noise when activating the loop:
https://soundcloud.com/alexshriffs%2Fsuspect-origin-opa2314pa-ic
plugged directly into audio interface/DAW, starts with the 'action' (depth) control on the xenotron at 'zero' and then dials it in..

i tried a couple other delay builds, and none of them were making this noise.
i suspected the unique factor here was the OPA2134 in the magnetron (tayda-sourced).

so I pulled it out and put in a trusted mouser-sourced TL072.
noise gone. how about that.

i curious, so then i reluctantly unsealed a mouser-sourced OPA2134 and tried that out.
yep, no worries all good.


IMG_8750.jpeg
tayda 'OPA2134' or whatever the fuck it actually is...

vs.

IMG_8751.jpeg
mouser-sourced OPA2134

i probably should've just left the TL072 in there and saved this OPA2134 for something else, but the sockets have copped it enough already.

but at least it's actually getting used though - the other guitarist in the band i'm playing in seems to prefer this over the (vero) seabed/deep blue delay
 
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owlexifry said:
yep. pretty much exactly what @spi said.


cheers 🤙🏻
yeah it’s weird, i don’t understand why it’s that weak, when compared to the dark rift where the modulations on that are wild and awesome but very controllable.


probably, i wouldn't know though.

Alright, well since this build report got bumped, I have an update to provide regarding FAKE OPAMPS.

So when i was testing out the FX loop in the recently finished xenotron, i thought i'd try this magnetron in there.
well, HOLY CRAP, check out this noise when activating the loop:
https://soundcloud.com/alexshriffs%2Fsuspect-origin-opa2314pa-ic
plugged directly into audio interface/DAW, starts with the 'action' (depth) control on the xenotron at 'zero' and then dials it in..

i tried a couple other delay builds, and none of them were making this noise.
i suspected the unique factor here was the OPA2134 in the magnetron (tayda-sourced).

so I pulled it out and put in a trusted mouser-sourced TL072.
noise gone. how about that.

i curious, so then i reluctantly unsealed a mouser-sourced OPA2134 and tried that out.
yep, no worries all good.


View attachment 99568
tayda 'OPA2134' or whatever the fuck it actually is...

vs.

View attachment 99563
mouser-sourced OPA2134

i probably should've just left the TL072 in there and saved this OPA2134 for something else, but the sockets have copped it enough already.

but at least it's actually getting used though - the other guitarist in the band i'm playing in seems to prefer this over the (vero) seabed/deep blue delay
Click to expand...
That noise is seriously cool. Make music with it!
 
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