MN3007 ADA Flanger Clone Questions

[moosapotamus]

Back when I built the SAD1024 version, I only initially used the frequency counter in my DMM to set the sweep range. Using the freq counter also helped me see what the trim pots were really doing. But eventually I ended up tuning the sweep by ear to get it exactly where I liked it.

~ Charlie

[StephenGiles]

Back when I built the SAD1024 version, I only initially used the frequency counter in my DMM to set the sweep range. Using the freq counter also helped me see what the trim pots were really doing. But eventually I ended up tuning the sweep by ear to get it exactly where I liked it.

~ Charlie

That's the whole point, "exactly where I liked it" - which is where I come from.

[Tantalum7]

Well, further inspection revealed that my DMM does have a frequency counter.  So "where I like it" will be about the best I can do until I track down one of my colleagues with a scope (I won't track them down with the scope, but you get my point)   Since I'm not about to go on tour or record a major album this week, that should do fine.

[Paul Marossy]

OK, so as suggested by some other builders of the MN3007 ADA Flanger clone, to get a much better sounding and more useable unit, I changed R65 from an 82K to 150K, added a 22K resistor in series with C37 and changed the Threshold pot from 10K to 100K.

Last night I followed the ADA calibration procedure, did the frequency counter thing and looked at the waveforms on the scope to make it as symmetrical as possible and all that. I thought I had it sounding pretty good doing everything by ear, but when I followed ADA's original calibration procedure, it went from sounding OK to sounding fantastic! 

I didn't think flanging could be so good.     

[StephenGiles]

OK, so as suggested by some other builders of the MN3007 ADA Flanger clone, to get a much better sounding and more useable unit, I changed R65 from an 82K to 150K, added a 22K resistor in series with C37 and changed the Threshold pot from 10K to 100K.

Last night I followed the ADA calibration procedure, did the frequency counter thing and looked at the waveforms on the scope to make it as symmetrical as possible and all that. I thought I had it sounding pretty good doing everything by ear, but when I followed ADA's original calibration procedure, it went from sounding OK to sounding fantastic! 

I didn't think flanging could be so good.    

I'd love to hear a sample or two if you have the time. I have the house to myself on Sunday afternoon so it won't matter if I make setting up noises

[Paul Marossy]

OK, so as suggested by some other builders of the MN3007 ADA Flanger clone, to get a much better sounding and more useable unit, I changed R65 from an 82K to 150K, added a 22K resistor in series with C37 and changed the Threshold pot from 10K to 100K.

Last night I followed the ADA calibration procedure, did the frequency counter thing and looked at the waveforms on the scope to make it as symmetrical as possible and all that. I thought I had it sounding pretty good doing everything by ear, but when I followed ADA's original calibration procedure, it went from sounding OK to sounding fantastic! 

I didn't think flanging could be so good.    

It's lots of fun, this MN3007 flanger clone! 
I'd love to hear a sample or two if you have the time. I have the house to myself on Sunday afternoon so it won't matter if I make setting up noises

I'll see if I can record something this weekend that shows all the variety of sounds possible. I even found one setting that has a bit of a sitar-ish quality to it, which is really cool.

I think a lot of the music I have listened to in the past has made use of the ADA Flanger, there are a lot of familiar sounds which I can't quite put my finger on when it comes to naming tunes or who did them, but the same textural quality is there. Anyway... when I'm playing thru it, there's a very familiar and pleasant quality to it, and it's a sound that I haven't been able to get until now.

[StephenGiles]

Many thanks

[Tantalum7]

OK, so as suggested by some other builders of the MN3007 ADA Flanger clone, to get a much better sounding and more useable unit, I changed R65 from an 82K to 150K, added a 22K resistor in series with C37 and changed the Threshold pot from 10K to 100K.

Last night I followed the ADA calibration procedure, did the frequency counter thing and looked at the waveforms on the scope to make it as symmetrical as possible and all that. I thought I had it sounding pretty good doing everything by ear, but when I followed ADA's original calibration procedure, it went from sounding OK to sounding fantastic! 

What did you end up changing when you actually did follow the calibration procedures?  Could you list your rough trim pot settings now that it's sounding great?  I won't have access to a scope for a bit, and I'm hoping that I can get something decent with just the frequency counter.  Thanks.

[Paul Marossy]

OK, so as suggested by some other builders of the MN3007 ADA Flanger clone, to get a much better sounding and more useable unit, I changed R65 from an 82K to 150K, added a 22K resistor in series with C37 and changed the Threshold pot from 10K to 100K.

Last night I followed the ADA calibration procedure, did the frequency counter thing and looked at the waveforms on the scope to make it as symmetrical as possible and all that. I thought I had it sounding pretty good doing everything by ear, but when I followed ADA's original calibration procedure, it went from sounding OK to sounding fantastic! 

What did you end up changing when you actually did follow the calibration procedures?  Could you list your rough trim pot settings now that it's sounding great?  I won't have access to a scope for a bit, and I'm hoping that I can get something decent with just the frequency counter.  Thanks.

I didn't really change anything on the calibration procedure, I pretty much followed it exactly. You really need a scope to get the waveform as symmetrical as possible when adjusting the BBD bias as there's a very small range where you hit the "sweet spot", where it sounds like it really comes alive.

[Tantalum7]

Thanks.  I guess I'll have to track down someone with a scope then.  Just knowing how good it could sound is enticing enough to want to do it right. 

[Paul Marossy]

I uploaded an off-the-cuff soundclip of my flanger clone here: http://improvisingguitarists.ning.com/profiles/profile/show?id=28c2tt8oagi7d - It's #42 on the music player, at the very bottom. A bad patch cord made the stereo signal cut out on the left channel a couple of times, sorry about that. 

One thing about my build is that the effected output level seems to be a little low, IMO. I changed out the two resistors R41 & R42 to 33K as suggested in the build notes, but the output level compared to the bypassed singnal level still seems a bit low to me. Is this something that is common to all flangers?

[neil411]

Paul, I changed R41 and R42 to 27K and added the A10k pot as a volume knob. I can turn the volume down to nothing, and up to better than unity, but it's still not a loud pedal.

[Paul Marossy]

Paul, I changed R41 and R42 to 27K and added the A10k pot as a volume knob. I can turn the volume down to nothing, and up to better than unity, but it's still not a loud pedal.

OK, then it sounds like it's probably "normal" then. For the ADA Flanger clone at least.

[StephenGiles]

How nice to hear an undistorted guitar Yes, the sample sounds perfectly normal for an ADA - I must have good ears!!

[Paul Marossy]

How nice to hear an undistorted guitar Yes, the sample sounds perfectly normal for an ADA - I must have good ears!!

Cool, sounds like I am on the right track then. I haven't played around with real ADA Flangers much, I've only tweaked and/or repaired them for other guitarists...

[StephenGiles]

How nice to hear an undistorted guitar Yes, the sample sounds perfectly normal for an ADA - I must have good ears!!

Cool, sounds like I am on the right track then. I haven't played around with real ADA Flangers much, I've only tweaked and/or repaired them for other guitarists...

NO, I'm just going on the two I built and the two I breadboarded - very nice sample/

[Paul Marossy]

How nice to hear an undistorted guitar Yes, the sample sounds perfectly normal for an ADA - I must have good ears!!

Cool, sounds like I am on the right track then. I haven't played around with real ADA Flangers much, I've only tweaked and/or repaired them for other guitarists...

NO, I'm just going on the two I built and the two I breadboarded - very nice sample/

Oh, OK. Thanks!

[Tantalum7]

I finally got my A/DA clone wired up, but something odd seems to be happening.  Every time I begin to power it up, R62 starts to burn up.  This is a resistor that seems to be part of a voltage divider from V+ along with the max clock trim pot.  It's attached to pins 4 and 10 of the IC3 LM324 op amp.  About the only thing I was able to measure before the resistor started smoking was the voltage of pin3 of the voltage regulator.  I had a full 18VDC going in and pin 3 was reading just under 15VDC so IC7 seems to be doing it's job.  Any suggestions?  I replaced the resistor and guaranteed that the replacement was the correct value (47R) and it burned up just as fast.  Thanks.

[mdh]

Burning up resistor = too much current flowing through the resistor.  From looking at the schematic, it seems that this can only be due to the series resistance to ground being really small (or nonexistent), or IC3 sourcing too much current for some reason.  I would remove IC3 (if it's convenient), and measure the resistance to ground from the junction of R62 and R63.  With the IC out, it should read about 60k.  If it's a dead short, there's your problem, and you should look for solder bridges.  Other than that, I don't know if electrolytic caps or op-amps can fail in such a way as to produce a short, but if so, C26 and IC3 would seem to be your best candidates.

[Tantalum7]

Since I had written my question, I noticed that I had omitted the SPDT switch.  I'm not sure if this could contribute directly to the problem, but it can't help.   I just installed that switch and replaced R62 again.  I'll try your suggestions and see what I get.  Thanks again for the rapid response.  I ordered duplicates on every component just in case anything got fried from my mistakes. 

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