question about ac to bipolar 12vdc and shock hazard

[caress]

i'm building a spring reverb like this one:
http://solorb.com/elect/musiccirc/reverb2/index.html

i've added this circuit snippet in between the reverb recovery and the output stage for a reverb tone control:
http://members.tripod.com/roymal/ReverbTone.htm

i've used this power supply setup without the 9vdc regulators:

also, i'm taking the +12vdc tap and sending it to the proper vref as shown in the reverb schem.

-- so my problems are --

1.  using the right ac adaptor?  i've tried two different adaptors, both neg tip 9vac (one 100ma the other 830ma).  my meter is on its last legs so i was only able to check the ac volts really quick.  i was getting somewhere between 10-13v from the 100ma, closer to 16v from the 830ma.  I GOT A SHOCK through the meter lead while i was checking the voltage...?!   

2.  i triple checked my wiring after my first attempt where one of the 2200uf caps was in backwards.  it just started to smoke but i quickly took it out before anything serious happened.  i swapped it for a new cap and oriented it correctly.  could i have fried any ics, regulators, etc from this little mistake?

3.  while using an audio probe to check the signal path I GOT A SHOCK when i tested the middle lug on the 1st (input level) pot!  wtf.....  does this mean i have dc or ac in my ground??

i'm a bit nervous to keep trying so i won't until i get a new meter today...but i guess i was wondering if anyone could shed a little light on this situation.
also, the tone control circuit is wired to +/-12v, but is not in the signal path yet - i wanted to make sure the core circuit worked before i made the path more complex.

[CGDARK]

1.  using the right ac adaptor?  i've tried two different adaptors, both neg tip 9vac (one 100ma the other 830ma).  my meter is on its last legs so i was only able to check the ac volts really quick.  i was getting somewhere between 10-13v from the 100ma, closer to 16v from the 830ma.  I GOT A SHOCK through the meter lead while i was checking the voltage...?!   

1) Check your adaptor, because AC adaptors don't have negative or positive tip. They are just AC.
2) This circuit is a voltage quadrupler (be careful it can be dangerous) so it will need a high power AC adaptor in order to be able to drive the regulators properly and deliver the current output needed. Ohm's law?

CG

[caress]

1) Check your adaptor, because AC adaptors don't have negative or positive tip. They are just AC.
2) This circuit is a voltage quadrupler (be careful it can be dangerous) so it will need a high power AC adaptor in order to be able to drive the regulators properly and deliver the current output needed. Ohm's law?

CG

1.  oh yeah...they don't actually say neg tip, but i use them for my ms2000, which uses 9vac and above the jack shows a little neg tip picture.  they work fine with the keyboard...
2.  i'm trying to be as careful as possible.  i don't want to get shocked badly or killed just trying to make some sounds...   i'll brush up on my reading a bit more and maybe use a different supply.  one that uses 15v ac and no voltage quadrupler...i'll try this one?  - http://www.thesquarewaveparade.com/images/ac-to-dc-bipolar.gif

[Transmogrifox]

Why don't you just get a 12VDC wall wart and make a V/2 reference for the tone control?  It isn't a requirement to operate the tone control on +/-12V unless you expect to be feeding it significantly amplified signals.

On the tone control,
connect pin 4 to ground
connect pin 8 to 12VDC
Use (2) 10k resisors to divide 12V into 6V
Bias pin 3 at 6V

The entire circuit would require a single 500mA, 12V wall wart.   This is significantly easier than using an AC adapter and SoundLab PSU.  The reverb schematic includes enough PSU filtering that you could just use an identical network to "VF2" to provide 12V to the tone control.

I hope that is helpful.

As for the shocking, there is nothing that should be shocking you if everything is correctly wired, and the AC adapter is in good condition.  The AC adapter should be a transformer, completely isolated from the 120V AC source. 

As noted above, this is a voltage quadrupling circuit, so you very well may experience a shock if things are not done quite right.

[CGDARK]

1) Check your adaptor, because AC adaptors don't have negative or positive tip. They are just AC.
2) This circuit is a voltage quadrupler (be careful it can be dangerous) so it will need a high power AC adaptor in order to be able to drive the regulators properly and deliver the current output needed. Ohm's law?

CG

1.  oh yeah...they don't actually say neg tip, but i use them for my ms2000, which uses 9vac and above the jack shows a little neg tip picture.  they work fine with the keyboard...
2.  i'm trying to be as careful as possible.  i don't want to get shocked badly or killed just trying to make some sounds...   i'll brush up on my reading a bit more and maybe use a different supply.  one that uses 15v ac and no voltage quadrupler...i'll try this one?  - http://www.thesquarewaveparade.com/images/ac-to-dc-bipolar.gif

Yes, that one will be less dangerous and easier to manage.

Good luck!

CG

[caress]

Why don't you just get a 12VDC wall wart and make a V/2 reference for the tone control?  It isn't a requirement to operate the tone control on +/-12V unless you expect to be feeding it significantly amplified signals.

On the tone control,
connect pin 4 to ground
connect pin 8 to 12VDC
Use (2) 10k resisors to divide 12V into 6V
Bias pin 3 at 6V

The entire circuit would require a single 500mA, 12V wall wart.   This is significantly easier than using an AC adapter and SoundLab PSU.  The reverb schematic includes enough PSU filtering that you could just use an identical network to "VF2" to provide 12V to the tone control.

this sounds like a great idea.  i didn't know you could convert a bipolar setup like that to single supply so easily.  is that common to most bipolar setups? (i'm sure there are exceptions...)  is the bipolar supply simply increasing the headroom?

[Transmogrifox]

You could use a 24V single supply and do the same thing for headroom.  A dual supply is often better in an application where you have a lot of different circuit functions in the same box.  This would be like a guitar amp, where you really need the low impedance common ground to sink the large currents to/from the speakers.  Since you already have the bipolar supply, then it makes the design process easier.

When making stompboxes, it's often easier to bend the circuits around the "dime-a-dozen" 12V wallwarts that you can get for 50 cents at goodwill.  All that is required is a little bit of care in filtering the DC supply (which is a requirement for DIY bipolar supplies as well), and some regulation.

I hope that works well for you.  This "V/2" reference point is very common in stompbox circuits.  Do a search for "Virtual Ground", "Vb", or "V/2" and you'll probably turn up a lot of threads similar to this one.

take care