Madbean Loophole (mobius looper), IC-change? ISD25xx 40sec Mod?

[PereatMundus]

Hey
I just built the loophole and I LOVE it.

http://madbeanpedals.com/projects/index.html
http://madbeanpedals.com/projects/Loophole/Loophole.pdf

I don't know why but its fidelity is far superior to what I've heard on youtube clips 
Spent over two hours  tweaking knobs and getting to know it with Isolated headphones.
Dunno if its a mix of pedals but it really didn't feel all that lo-fi to me.

But then I mostly..  used it in conjunction with about ten pedals..

and well I like the lo-fi and noisy sound.. so , irrelevant observation probably.

I wonder a bit how close the Loophole is to the tone gods Payback
http://tech.thetonegod.com/payback/payback.html

and If it could be modded to use the ISD25xx  IC chip instead for a full 40sec loop

What do you think?



Pinouts don't look all that different, and from what I can tell from the literature the ISD25xx is an updated version of the obsolete ISD1000A series.

The pins: differences

   ISD10xx                      ISD25xx
22: NC                             OVF
7:   NC                              A6
8:   NC                              A7
9:   A6                              A8
10:  A7                              A9

Oh, and searching ebay and the net you can get ISD10xx and ISD25xx chips  here and there for cheap.

seems its a question of the mobius or payback style of DIY looper.
I dont really understand if the IC's are interchangable thou.
did see theToneGod says payback can only use ISD25xx chips etc. and yea the pinouts dont really match fully, but can the loophole (mobius based) use the 40s ISD25xx chips? *with pinout correction done ofcourse.

[Jaicen_solo]

Unfortunately, the 1000 series is not 100% pin compatible. Personally, I'd just build a payback v1, well, I did. Why reinvent the wheel?

[PereatMundus]

Unfortunately, the 1000 series is not 100% pin compatible. Personally, I'd just build a payback v1, well, I did. Why reinvent the wheel?

Read the whole post,before you reply.  my question is mostly about the pins and they are listed at the end.

Because Like stated above, the pins do not vary that much and the ISD25XX have a longer built in storage.
40s vs 20s if I understand correctly.

So doubling the loop, isn't really reinventing the wheel..  >.>
Hell changing an IC and re-routing 2 pins for a doubled "capacity" is no big deal. IF there isn't anything else to change, wich I dont seem to find
and why I'm asking.

(and the buffers, noise control etc. in the mobius Loophole madbean layout, works so damned well I rather use that.)

[Jaicen_solo]

Ok, read the datasheets before you start a thread.

[PereatMundus]

Ok, read the datasheets before you start a thread.

ok, so I missed something?
re-reading. any chanse you can hint as to what I missed?
//
Listen, I'm looking for a simple answer if the original premiss is correct or not.
If so, It would be good for anyone having built the GGG mobius or the madbean Looper. so they get a better product with just an easy mod.

Reading the Datasheets only get you so far unless you really know what your doing. sure Ive done some 50 stomp-boxes.
However a looper-pedal and this kind of thing gets advanced fast when your talking about the IC (the analog wrapper is simple enough)

I did get a bit agressive in my responce there cause I hadnt have my coffee yet and you pretty much just wrote what I had already stated in
the original post, as well as critique'ing the premiss as a whole.

Not looking for reasons NOT to build it this way It's already built. just looking to see if the Idea of a modification on this layout is possible.
It's not a question if its better or worse place to start from scratch.


Perticularly since The datasheets differ from one another and there is no nice guide to ISD10XX as there are made by the tone god for the ISD25xx
And in actuality seeing build reports that wary from 8-10s recording to 40-50s recording.

[edit: ISD2540 = 40s recording ISD2564 = 64s recording and so on.. , thing is the ISD1020 is pretty much the only ISD10xx series you can buy ]

And I'd rather get an honest opinion by someone else before I order a couple  of chip for 10-20 US$

Edit: and ofcourse I asked this question on specific forums first before asking here in the general diystompboxes forum.  
aswell as searching the forums reading payback and mobius threads.
(noone knew for sure on other places, but they did try and help)

[Jaicen_solo]

Ok, lets start again then shall we.

Having looked at it a bit further the Madbean pedal seems to be using the operational mode for looping purposes.
It should work if you plug in a 2560 provided that you also ground the unused address pins. You will not be able to use multiple messages with this design.

The reason I mentioned that it is not 100% pin compatible, is that in looping mode the  25xx series address pins are locked out for a fraction of a second on startup, and then read.
Depending on the timing delay inherent in the Madbean design, this may or may not be long enough for the 25xx series to work.
At the minute, I don't really have time to work out what's going on with the Madbean design, but if I get time I'll go through it and get back to you.

If you can source the chips, you may as well see if it works, as you only need to solder in a couple of pins to ground.
If it doesn't work, you can always use the chips to build a payback.

[dorrisant]

Did anyone ever verify if the 25xx chips could work here? Has anyone tried it?

Tony

[EDIT] After further review... It does work. Look here:

www.madbeanpedals.com/forum/index.php?topic=2172.15