for rebote delay(2) builders

[tam]

hello,
regarding the rebote 2- do you guys expirience this hushi noise coming from the repeats-(only at longer delay settings)?
is that the chip making this noise?
thanks

[Triffid]

I recently put this together on bread board and had the same question... so i'll bump.   The repeats don't exactly seem to be same quality of signal as the original.  I guess this makes sense since it is a copy.  For me it seems to add a slight distortion...  more noticable at longer delay settings.  It isn't that bad and is probably useable for me in it's current state, but does any ideas on what to try to make a more pleasing echo?

Thanks

[tam]

seems like this subject is a taboo..... :?

[strungout]

...or there already plenty of info about the quality of delays and how to fix it in the forum if you do a search?  :wink:

[Triffid]

there is always someone who assumes the other guy didn't do a search... to bad...  I read every post on rebote 2 and all i could find is people saying the pt80 was better... which doesn't answer my question

i mean really why post just to say search for it... does that give you cool points or something?

If you would look at the dates on the post you would realize that i was searching when i came across this thread

[geertjacobs]

PT2399 is the cause of the noise at longer delays.
Try a search on PT2399 for more info  :wink:

[Fret Wire]

Cutting treble and adding a little dirt to the repeats is how these digital delays emulate anolog delays. Perfect, sterile sounding repeats is what turns some people off on digital. It's pretty simplified explanation, so read up on what Scott Swartz (PT-80 has to say on the subject.

http://www.generalguitargadgets.com/index.php?option=content&task=view&id=48&Itemid=80

[Rob Strand]

Cutting treble and adding a little dirt to the repeats is how these digital delays emulate anolog delays.

There's nothing magical about analog delays.

Analog delays cut the hi's with filters too.  If you want a digital delay to sound like the analog it stands to reason you have to use the same filtering!  The same applies to chorus and flanger units.

A lot of people think the Boss CH-1 is digital because it sounds sterile - it's actually analog.  It's essentially an analog unit without filtering and hence sounds like the "perfect" digital units (which don't use much filtering).

[Triffid]

Thanks for the help guys, for what it is worth i am now completly happy with my rebote 2.  I made the following simple changes to my liking...

1.  Remove the 0.01 cap from the 15k, 10k resistor junction near the input to the pt2399... this seemed to give me a more pleasant echo (to my ears of course)

2.  The max wetness was too much for me so i added a 15k resistor from the 1uf, repeat pot lug junction to the wet pot lug.  Max echo volume is now just slighely louder then the original.

3.  The min wetness turned up some oscillation so i swapped the ground connection from the wet pot with a 1k resistor to ground... solved that problem

4.  I changed the 100k pot for repeats to 50k, gives a good range... from single slap back to many repeats

5.  I swapped the 50k delay time pot to 100k, more gritty with longer delays, but suitable for my needs.

I will now be completing the build and am looking forward to a finished box  I really love the sound with a good fuzz in front of it, good pink floyd sound.  I can post some samples if anyone is interested.

Thanks again for the help.

[tam]

try recording one sample with the longest delay time,and with a clean sound.....

thanks

[Triffid]

Well, i think it is unrealistic to try to get anything real clean from the pt2399 after a 500ms delay.  But i actually enjoy the not so perfect echo.  It doesn't take control of the sound like other delays.  I will do some recording when i get home from work.  I had fun playing with my si fuzz --> rebote2 --> cheap tube amp for a couple of hours last night ... holding the notes and bends were very pleasing.

[tam]

i wonder how does the new chips from small bear (PT2395,PT2396)
react to longer delay times....anybody tried?

[Triffid]

I have one of the pt2395 chips i pulled out of a broken dan electro delay.  Though it may be the chip that was broken.  Maybe i'll check out the data sheet to see if it would be difficult to merge the 2 designs

[Triffid]

Lol, second hit on google...

//http://www.cgs.synth.net/modules/cgs44_ddb.html

Seems like the same sort of design as the pt80... though it is some sort of development board

[Triffid]

Ok, at least one person is reading so here are my recordings.  These are just recorded with my computer mic so sorry for the bad recordings.  The first 2 came out a bit muddy, i repositioned the mic for the second 2.  I realize it is pretty pointless to try to show of lo fi echos with this setup  but i think you can still tell.  

Here is just my strat to my tube amp... delay bypassed
http://castagno.org/clean.mp3

Shorter delays, still clean...
http://castagno.org/s1.mp3

Here is one with longer delays then speced... you can here the grittyness a little
http://castagno.org/long3.mp3

Here is my si ff through the rebote2
http://castagno.org/ff.mp3

Again, sorry for the bad recordings

[tam]

hi triffid,
thanks for the recordings.
your si ff sounds great.the rebote 2 sounds just like mine.....
its impossible to use with longer delay times - cause the sound is terible....but its defintly useble with shorter delays....as a slap delay-or for running vocals through it and getting this "elvis" sound....

[Triffid]

One thing that i noticed that if i turn the treble down on my amp, the longer repeats become less gritty, of course they don't have much treble either.  So I think I might try adding some sort of variable low pass filter at the ouput of the pt2399 (before the mix) to see if i can get a usable signal with long delays.  They will have much of the highs rolled off, but might still sound ok.  I'll let you know how it goes.

[HrD]

hi!
i've ultimated...the reboote 2 delay..five minute ago...and i've the same problem of distortion on log delay time ...the efx is great until it distorce..
please find a solution  :roll:

[geertjacobs]

Check this other thread with some great comments of Mark Hammer.
http://www.diystompboxes.com/sboxforum/viewtopic.php?t=30710&start=0&postdays=0&postorder=asc&highlight=
He explains some possible mods for the PT-80 in regard to this problem , the mods are also valid for the Rebote 2.

G.