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DIY Stompboxes => Building your own stompbox => Topic started by: glenn.b on May 06, 2012, 08:24:32 PM

Title: Self contained small DIY spring reverb- wiring help..mostly
Post by: glenn.b on May 06, 2012, 08:24:32 PM
Hi folks!
    I saw THis:   http://www.diystompboxes.com/smfforum/index.php?topic=87780.0 / last night and was amazed! I've been wanting a reverb besides my ggg reverb.  As it is, I already have some 3 inch springs leftover from a reverb unit that was in my first car, a '69 Dart GT.  The springs are very light , and I also have transducers, though not completely certain at this point if I need them for this or not. (?? )
(http://i895.photobucket.com/albums/ac158/glenndude/101.jpg)
(I hope the pic comes out :-\ :icon_confused)
Anyhow I was hoping the wiring could be made a bit more clear.  Thanks in advance!
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: joelindsey on May 06, 2012, 10:44:07 PM
Quote from: glenn.b on May 06, 2012, 08:24:32 PMhave some 3 inch springs leftover from a reverb unit that was in my first car, a '69 Dart GT.

Cars had built in reverb back then? That's amazing!

When you say you have transducers, do you mean the two yellow ones that are already on the spring assembly or other ones? I'm not really sure what your question is.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: glenn.b on May 06, 2012, 11:14:17 PM
My first car was a '69, but I first drove it in'86!   :icon_biggrin:  But yes, what I am calling transducers ( perhaps even wrongly!) are the 2 little yellow things on the end of the springs.   As far as the reverb system in the car, the"audiophile" driver insisted on not only be 1 speaker in the dash, but a special extra speaker and the rear of the vehicle. If They were really into music They would have a reverb system installed in the back as well.  The amount of blend was controlled by a knob in the dash.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: glenn.b on May 06, 2012, 11:34:21 PM
I just read my post, and it lacked clarity.   The below layout is where I want to employ my springs ;)


(http://i895.photobucket.com/albums/ac158/glenndude/11gqf0yjpg.png)
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: petey twofinger on May 07, 2012, 12:21:09 AM
i wonder if that circuit would work with a "real" spring tank ?
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: Earthscum on May 07, 2012, 12:29:01 AM
I think the transducers are going to be needed. One drives the springs, and the other picks up the resulting reverberation. All you're gonna need to do is look up a spring reverb driver (LM386, as you're thinking, has been done, and should be a good option). Do the transducers or the unit have any numbers on it, any indication of any ratings?
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: joelindsey on May 07, 2012, 12:32:47 AM
For what it's worth, a few months ago I built the reverb circuit here: http://sound.westhost.com/project34.htm (http://sound.westhost.com/project34.htm) ... I cut out the mixing section (leaving nothing but wet signal) because I didn't need it and added a tone control. It's sounded very nice with guitar, organ and voice so far. I used an accutronics 4AB3C1B, which is an 8 ohm input impedance and 2250 ohm output impedance.



... One thing I will say is the lm386 will distort pretty easily if you don't keep tabs on the input level. I've wondered if instead of the 368 something like an FET booster going into one of those $3 audio output transformers from radio shack would be better.

http://www.radioshack.com/product/index.jsp?productId=2103254&CAWELAID=107597296 (http://www.radioshack.com/product/index.jsp?productId=2103254&CAWELAID=107597296)
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: Earthscum on May 07, 2012, 01:15:55 AM
You could try a BTL with a TDA2822. It should be a pretty clean chip, and you're still only looking at an 8-pin DIP. And if you WANT it to distort, well... it does that, too.  :icon_biggrin:
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: glenn.b on May 07, 2012, 12:35:29 PM
Thanks for all the ideas & comments! :)
QuotePosted by: Earthscum
Insert Quote
I think the transducers are going to be needed. One drives the springs, and the other picks up the resulting reverberation. All you're gonna need to do is look up a spring reverb driver (LM386, as you're thinking, has been done, and should be a good option). Do the transducers or the unit have any numbers on it, any indication of any ratings?
Posted on: Yesterday at 10:21:09 PM Posted by: petey twofinger
Agreed on the need part.  No markings to speak of. So if I have transducers, it eliminates the need for a pieazo pickup, like in Top Tops' build?

QuotePosted by: joelindsey
Insert Quote
For what it's worth, a few months ago I built the reverb circuit here: http://sound.westhost.com/project34.htm ... I cut out the mixing section (leaving nothing but wet signal) because I didn't need it and added a tone control. It's sounded very nice with guitar, organ and voice so far. I used an accutronics 4AB3C1B, which is an 8 ohm input impedance and 2250 ohm output impedance.
I did see that while searching the ends of the earth for a simple reverb, and there is no doubt that one is simple.   But of late money has gotten extremely tight in my household, which means, no ordering a Accutronics spring assembly(s).  So I'm trying to be very practical and get the most bang, er..I mean "boinggg" outta what springs  I have on hand.

QuotePosted by: Earthscum
Insert Quote
You could try a BTL with a TDA2822. It should be a pretty clean chip, and you're still only looking at an 8-pin DIP. And if you WANT it to distort, well... it does that, too. 
:icon_twisted:    Noooo!  I want distortion from somewhere down the line of effects/and/or the amp, but not the reverb!   But then, you say it can run clean?  Cleaner the the 386?

...I'm still clueless about the wiring of the above posted "MiniSprings" reverb.   Shoot, maybe I'll post a pic of the whole reverb from my car-as it sits next to me on my kitchen table.  Maybe someone with some true experience would know how to retrofit it to a guitar effect...Need someone like R.G.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: Mark Hammer on May 07, 2012, 01:32:07 PM
Quote from: joelindsey on May 06, 2012, 10:44:07 PM
Quote from: glenn.b on May 06, 2012, 08:24:32 PMhave some 3 inch springs leftover from a reverb unit that was in my first car, a '69 Dart GT.

Cars had built in reverb back then? That's amazing!

When you say you have transducers, do you mean the two yellow ones that are already on the spring assembly or other ones? I'm not really sure what your question is.
http://www.swtpc.com/mholley/PopularElectronics/Feb1966/PE_Feb1966.htm
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: Earthscum on May 07, 2012, 01:34:45 PM
Well, heck... Take a shot of the whole unit. I think you'd be fine running the driver that was in there. Think about it this way: battery driven reverb is going to suck some power, so you probably want a wall wart. A car's electrical system is 12V, and 12V adapters are quite common. You may find that you just have to apply juice and figure out how to squeeze it into a stompable enclosure.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: joelindsey on May 07, 2012, 02:30:03 PM
Quote from: glenn.b on May 07, 2012, 12:35:29 PM
I did see that while searching the ends of the earth for a simple reverb, and there is no doubt that one is simple.   But of late money has gotten extremely tight in my household, which means, no ordering a Accutronics spring assembly(s).  So I'm trying to be very practical and get the most bang, er..I mean "boinggg" outta what springs  I have on hand.

it's possible that your spring assembly would work if the impedance was close. I've tried a small 600 ohm input tank with it and it works, but it just doesn't sound as good as the larger tank.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: glenn.b on May 07, 2012, 10:26:35 PM
Thank you Mark for the input!  That is going way back, but that is pretty close to what I have.  I wonder, if that was built, what more would be needed to use it for guitar playing?

QuotePosted by: Earthscum
Insert Quote
Well, heck... Take a shot of the whole unit. I think you'd be fine running the driver that was in there. Think about it this way: battery driven reverb is going to suck some power, so you probably want a wall wart. A car's electrical system is 12V, and 12V adapters are quite common. You may find that you just have to apply juice and figure out how to squeeze it into a stompable enclosure.
Yeah Earthscum, I have several 12 V DC warts.  Thing is, I had posted this on another board, but struggled to figure out how in the world it worked.  I would be glad to use it as is, if I only knew how to make it work.  Here is what it looks like altogether:
(http://i895.photobucket.com/albums/ac158/glenndude/2012-05-07_18-06-50_627.jpg)

And Please don't laugh, one of my weaknesses is schematics, so I did not understand this as I drew it, nonetheless I drew it out as best as I could, using AppleWorks.   :icon_eek:  The six lines at the bottom right represent all the lines in,  but I was at a loss which one was which.  ???
(http://i895.photobucket.com/albums/ac158/glenndude/IKAgUR.jpg)
So I guess I figure out how this thing works (inputs/outputs/power/switchin/pots etc.., or scavenge the springs and use them to build the MiniSprings, if I knew the wiring for it..

Quoteit's possible that your spring assembly would work if the impedance was close. I've tried a small 600 ohm input tank with it and it works, but it just doesn't sound as good as the larger tank.
Posted on: Today at 11:34:45 AM Posted by: Earthscum
That's true, the Springs assy. that was in the link that Mark posted was 8 ohms input by 2000 ohms output.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: zambo on May 11, 2012, 04:42:16 AM
has anyone tried a fet boost with the 3 dollar 1k to 8 ohm transformer?  I just built one with a set of lpb1's one as a buffer for the dry signal and one into a 1 or 2 watt vellman amp ( 9 dc) into a 8 ohm in  tank 2250k out . Output goes into a SHO and rejoins the dry signal. Would be nice to get rid of the amp in the front and just use a fet boost. could it be a SHO with that transformer?
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: zambo on May 11, 2012, 05:44:52 PM


here is what i got so far with this 8 ohm tank. The lpb1's that i am using for buffers are coloring the signal to much. losing a lot of highs . Its killin my high man.....yeah.. other than that i really like this thing. worth exploring more for sure. anyone got a cleaner boost or buffer? Ideas ?

http://www.youtube.com/watch?v=PldsLFUN0vQ&feature=youtu.be
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: zambo on May 13, 2012, 04:29:06 PM
no takers on this one?
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: glenn.b on May 14, 2012, 12:14:55 AM
 zambo!    Love it.... that's about what I'm talkin bout!  Reverb done easy... I am going to watch that again tomorrow when I'm not tired.  So far my mind is wrapping around that  pretty easily.  Got yur springs, 2/3 watt amp,a buffer,on the "other" side a SHO,(Gee wonder if a "crackle NOT ok" will work in lieu of an actual SHO circuit. ;)   actually how to build a little two watt amp using a LM386??like a headphone amp I think.  More tomorrow ....nice catch!!!
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: zambo on May 14, 2012, 12:48:56 AM
well I plugged it into my hi gain amp today and got some really strange results. When the crackle ok knob is at its loudest I get a fuzzy, bad solder joint kind of sound. If I turn it down I can kind of tune it out to a degree but it sounds like I can hear white noise in the background. Also if I push the amp to hard I get a sound like a blown voic coil will sound sometimes. Like a rattly squeak sound that happens when you play a muted low note. I am thinking its starving for voltage? maybe? I dont know what the crackle pot is doing, That might be oscilations? I have no idea. Is not as affected on a clean amp though. The whole thing is out in the open and I am wondering if sheilding will take care of some of it. Maybe I need another buffer at the output side of the dry signal to seperate the outputs of the reverb recovery (sho) and the input dry signal buffer ( lpb1). I am a little clueless and would love some help. The lm386 amp configured as a constant current amp (?) I hear works with 8 ohm tanks. I chased around all the links in this and a few other threads. It says 9 volts isnt really enough to push a higher ohm tank. you can run it on 12 or so though and it does better. Its around 1/2 watt at 12 volts I think. I really would like to get this sorted. I love the reverb sound from that tank. so surfy!! I still cant get the highs to come through on the dry side either. More buffers?
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: zambo on May 14, 2012, 12:53:07 AM
glenn - did you figure out what ohms your tank is? thanks for reply btw. I really want to build these. I have like four tanks of various ohms etc.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: glenn.b on May 15, 2012, 12:47:27 AM
QuotePosted by: zambo
Insert Quote
well I plugged it into my hi gain amp today and got some really strange results. When the crackle ok knob is at its loudest I get a fuzzy, bad solder joint kind of sound. If I turn it down I can kind of tune it out to a degree but it sounds like I can hear white noise in the background. Also if I push the amp to hard I get a sound like a blown voic coil will sound sometimes. Like a rattly squeak sound that happens when you play a muted low note. I am thinking its starving for voltage? maybe? I dont know what the crackle pot is doing, That might be oscilations? I have no idea. Is not as affected on a clean amp though. The whole thing is out in the open and I am wondering if sheilding will take care of some of it. Maybe I need another buffer at the output side of the dry signal to seperate the outputs of the reverb recovery (sho) and the input dry signal buffer ( lpb1). I am a little clueless and would love some help. The lm386 amp configured as a constant current amp (?) I hear works with 8 ohm tanks. I chased around all the links in this and a few other threads. It says 9 volts isnt really enough to push a higher ohm tank. you can run it on 12 or so though and it does better. Its around 1/2 watt at 12 volts I think. I really would like to get this sorted. I love the reverb sound from that tank. so surfy!! I still cant get the highs to come through on the dry side either. More buffers?

Whew!!   Lots going on there,  but I think your correct, at least partially :   A little more power 12/18 volts, perhaps.  I say this because if I am not mistaken,   the " Hot Springs" that Paia offers are meant to / capable of running at 18v, where there is more headroom.  White noise?  Yeah, that should improve with the addition on an enclosure-no tellin how much radio Freq. your picking up....anyway these are my guesses :-\ :icon_biggrin:
but YES, Surf stuff is what I am hoping for!  Gotta have it!

Quoteummary
Posted on: Yesterday at 10:53:07 PM Posted by: zambo
Insert Quote
glenn - did you figure out what ohms your tank is? thanks for reply btw. I really want to build these. I have like four tanks of various ohms etc.
I'm pretty sure....  I say that because I have not measured it per se,   but I think have identified it : It is a Gibbs Type 5G or 7G Reverberation Unit, 8 ohms input, 2000 ohms output.  This things is like circa 1950-60...To be honest I have not ever measured the ohms on this or any other reverb, so if you know the procedure I am all ears.
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: zambo on May 15, 2012, 01:59:39 AM
I found it on one of the many links that started in this thread. I will see if I can find it again. just looked and could find it. Did find this  http://www.tubesandmore.com/scripts/foxweb.dll/extpage@d:/dfs/elevclients/cemirror/ELEVATOR.FXP?page=TECH_REVERB  it looks like you can estimate it by measuring dc resistance. so if your s measures 1 ohm input more or less with a volt meter you have an 8 to 10 ohm tank. 25 ohms = 150 to 190 ohm tank . So you could get away with an lm386 driver then you just have to put a volume knob in front of it ( and a buffer in front of that to stop signal loss when you split the signal at input ) so it doesnt distort. You just need a sweet recovery amp then. I think the SHO will work but I do need to run sheilded wire and enclose it before I can make any real determination. I was chopsticking it tonight and I am picking up all kinds of junk when I move the signal runs. I did add another buffer/booster where the signals meet again and it made an improvement. I think this could work alright. will post more results tomorrow. Sorry about the novel  :icon_redface:
Title: Re: Self contained small DIY spring reverb- wiring help..mostly
Post by: mister707 on May 16, 2012, 07:37:43 PM
The "blue IC1" is not an integrated circuit, is a unit of couldplate (resistors and capacitors) are usually used in the control stage of the preamp tone, the mid-60. I do not understand the diagram you posted, the input and output signals, as he connected the button on the dash?  :icon_eek: