Echo Base - a new PT2399 delay

[Taylor]

Oh for sure. I mean, by conventional and proper terminology, PT2399 is digital, no doubt about it. So I'm not disagreeing at all, I was just proposing a bit of a new way of thinking about it.

But as far as how guitarists think about it, many guitarists think having any IC in a circuit means it's digital, so I don't think we should worry too much about their perspective... 

[El Heisenberg]

Hey can anyone tell me what lifting the 1N914 diodes will sound like? My board is face down and it be a hassle to try it out and put in another switch not knowing if id wanna keep it.

[slacker]

The diodes are mostly to limit the volume when the repeats pot is cranked right up, they don't do much if anything at lower settings of the repeats pot. If you hit the pedal with a hot enough signal they may add some slight distortion at lower repeat settings.

[slacker]

So maybe rather than 2 bins, analog and digital, we have a continuum.

tape - BBD - PT2399 - general-purpose DSP

The basically how I look at it, there's 2 types of digital delay. The first is where you have an analogue signal path and the only digital bit is what ever is producing the delay. This includes PT2339 based pedals and things like Boss DD3s, and a whole bunch of other older digital delays.
Then you have DSP based delays where the whole signal path is digital, like you get in multiFX pedals or newer EHX stuff. I don't really like these, not for the sound, some of them sound great, but because they don't have analogue controls, so you often can't mess with delay time in real time or they won't go into feedback for example. That's the main reason I stopped using a multifx board and went back to pedals and got into this whole business.

When people say they don't like digital delays I'm never really sure which sort they're talking about.

EDIT: Doh, just noticed that's basically what Phil said

[slacker]

 Due to the super simple wiring (I assume the bypass is just a open / closed switch for on / off?),

Yeah that's right one switch can control more than one board.

To do ping pong you would put 2 delays in series with both set to the same time, you could do this by using a dual pot for the time control or just set them both the same. Then you take feedback from the output of the second one back to the first. The output of one goes to the left and the output of the other goes to the right.
There's a ping pong delay at Build Your Own Clone, you could look at that for ideas.

[chromesphere]

Hey Slacker, thanks for the response, i think i'll look into doing this, doesnt sound to complicated. 

Thanks for your help!!!

Paul.

[tasos]

hey...i found a lot of pdf's for this pedal...which one is the latest please?

[slacker]

If you mean layouts then I think this is the one most people use http://blogs.yahoo.co.jp/anonymousfacelesscoward/23693577.html this is based on the version 1 schematic on the first page of this thread.

As far as I know the only layout for the latest version is the one Taylor sells.  

[tasos]

If you mean layouts then I think this is the one most people use http://blogs.yahoo.co.jp/anonymousfacelesscoward/18854450.html this is based on the version 1 schematic on the first page of this thread.

As far as I know the only layout for the latest version is the one Taylor sells. 

ok thanks!pdf was not clear enough sorry! i mean layout-schematic-wiring and so...!thanks again...

[Jerem]

I want to know how wiring of the footswitch? I believe we have to connect +9v on it?

[poodlebra]

hi all.

anyone help with an echo base build that isn't going into bypass mode? i assume it'll be something to do with the 2N5809, though only as that seems the logical place. i won't pretend to know much about what i'm doing 

i've measured the voltages on Q1:

On:
E 0, B 0.57, C 4.7

Off:
E 0, B 0, C 7.6

if that gives any clues i'd greatly appreciate any help, as this thing sounds pretty good, but isn't much use right now!

cheers

[slacker]

Looks like that's where the problem is, the collector voltage when On is too high, it should be about 1 volt or less. With 4.7 volts on the collector the switching will be on all the time.
Double check the connections and value of all the components around the 2N5089 and make sure the transistor is the correct way round.

If you want to check that everything else is working then touch the middle pin of the tails switch to ground and that should bypass the effect.

[Groovenut]

Ian

I am debugging an Echo Base that was built on one of Taylors boards by someone else. He has managed to install 1.5R instead of 1M5 resistors. I dont have any 1M5 on hand, only 1M. I am pretty sure the differences in the switching circuit are negligible, but what effect will putting a 1M in the feedback of U1B have verses a 1M5?

BTW, Taylor, you have the wrong pin numbers on your schematic vs the pcb. U1A 1, 2, 3 should be 7, 6, 5 and U1B 7, 6, 5 should be 1, 2, 3. Feel free to correct me if I'm wrong.

Thanks,

Law

[Taylor]

what effect will putting a 1M in the feedback of U1B have verses a 1M5?

It will slow down and increase the amplitude of the LFO.

BTW, Taylor, you have the wrong pin numbers on your schematic vs the pcb. U1A 1, 2, 3 should be 7, 6, 5 and U1B 7, 6, 5 should be 1, 2, 3. Feel free to correct me if I'm wrong.

You might be right that they don't match, because the schematic was drawn by Slacker, independently, after the PCB was already designed. I'll check it out, thanks.

[Groovenut]

Thanks Taylor! I appreciate the input

[slacker]

Yeah Lawrence you're correct using 1M instead of 1M5 in the audio sections won't make any difference. There was no particular reason I used 1M5 other than I wanted a high value and I had a load of them to hand.

[BitBum]

I just recently ordered the kit for a Thingamagoop 2. Me and a friend of mine who have an interest in electronics recently put it together. The only experience I have in electronics myself is I  just recently finished a course on electrical automation. I enjoyed assembling the Thingamagoop 2 so much that I instantly went looking for another electronics project so I could further educate myself. I decided on building this delay pedal and have being trying to compile the parts for this pedal from the schematics. I've got most of them but am having a hard time finding the non polarized capacitors and when I go to order them online I'm finding the variety of capacitors a little overwhelming. I was hoping someone might be able to give me some guidance on how to properly order these following components. 100n, 1n, 470p, 15n, 47n, 4n7, 220n, 1u, 1n. I hope this question isn't too rudimentary for this forum but this is the only way so far that I know how to learn this stuff. So far it feels like I might have bitten off more than I can chew but I'd really like to see this thing come to fruition. It seems like this is a really great pedal and would be lots of fun to build.

Thanks.

[Taylor]

smallbearelec.com carries the caps you need, and they have a small and focused enough selection that it won't be maddening to search through it all.   When I buy caps from there, I get the Topmay TCM07 series.

Http://www.smallbearelec.com/Detail.bok?no=892
Http://www.smallbearelec.com/Detail.bok?no=894
Http://www.smallbearelec.com/Detail.bok?no=896

Now, for values below .001uf, which is also called 1n, my suggestion would be to go with ceramic caps. There are film caps in those smaller values, but Small Bear doesn't carry them anymore. People argue sometimes over whether ceramic caps sound different from film - without getting into it, my personal belief is that, at least for a first pedal, I really don't think it matters.

[BoxOfSnoo]

I just recently ordered the kit for a Thingamagoop 2. Me and a friend of mine who have an interest in electronics recently put it together. The only experience I have in electronics myself is I  just recently finished a course on electrical automation. I enjoyed assembling the Thingamagoop 2 so much that I instantly went looking for another electronics project so I could further educate myself. I decided on building this delay pedal and have being trying to compile the parts for this pedal from the schematics. I've got most of them but am having a hard time finding the non polarized capacitors and when I go to order them online I'm finding the variety of capacitors a little overwhelming. I was hoping someone might be able to give me some guidance on how to properly order these following components. 100n, 1n, 470p, 15n, 47n, 4n7, 220n, 1u, 1n. I hope this question isn't too rudimentary for this forum but this is the only way so far that I know how to learn this stuff. So far it feels like I might have bitten off more than I can chew but I'd really like to see this thing come to fruition. It seems like this is a really great pedal and would be lots of fun to build.

Thanks.

For the "non-polarized" capacitors, just get Film (polyester film) capacitors.  They're always non-polarized.  You may be trying to get non-polarized electrolytics, which are harder to find and also unnecessary for this project.

Note also that smallbear uses "mf" in his product listings where projects will typically say "uF".  In this case, they're the same (but don't presume they're the same anywhere else).

Capacitor markings and types are always needlessly complicated... unfortunately.

[BitBum]

Thanks so much guys! that's a big help.