I have read that in some effects a battery might sound better than a power supply.
Electrically,
What does a battery induce / do to a circuit.
What could be added to a power supply circuit to mimic a battery.
(I don't believe it is a dieing battery)

A Dying Carbon-Zinc battery rises its internal impedance, and there is a theory that it swings the DC up and down as you play hard notes as there is a drop on that internal impedance. This is especially linked to Fuzz Face, which is a very dynamic circuit. I have measured it with a few exhausted Green Cell batteries, and it did not happen.

What does "better" mean?
Less noise? Could be, but I doubt that's what "they" meant.

About the Catalinbread Karma Suture (A harmonic perculator)

POWERING UP THE KARMA SUTURE
"Just use a standard 9 volt DC center-negative power supply for pedals. You can run it up
to 18 volts if you want but you may or may not get oscillation and other misbehaving
sounds. If you like that, go for it! Otherwise, it has been tuned to sound the best at 9
volts.
For even better tone and response, run a 9 volt battery instead. The pedal draws very
little current so a battery should last a good long time if you remember to unplug it or at
least bypass the pedal so that the LED is not on. You'll notice a warmer tone and better
dynamics with a battery."

Quote from: Phend on December 29, 2023, 09:00:50 AMYou'll notice a warmer tone and better dynamics with a battery."

Woo woo woo, woo woowoo woo?!?

Sounds like nonsense to me, Phend. Electrons don't know where they came from.

You certainly don't get mains hum with batteries!!

Quote from: ElectricDruid on December 29, 2023, 11:08:17 AM

Quote from: Phend on December 29, 2023, 09:00:50 AMYou'll notice a warmer tone and better dynamics with a battery."

Woo woo woo, woo woowoo woo?!?

Sounds like nonsense to me, Phend. Electrons don't know where they came from.

Tom i'd say "they" refer to the dying battery impedance causing the DC shifts, which is something i failed to measure.

Has anybody succeeded in measuring the dying battery impact on the dynamics?

A higher impedance and/or lower voltage power supply can only reduce transient response, so that would be objectively worse dynamics.
But don't think that's what Catalinbread are referring to either, I think they're just sprinkling meaningless buzzwords. At least I hope they didn't embrace the Woo.
An envelope-controlled power supply like the Punisher(?) can still be useful though.

The whole "dying battery" thing more or less began with Eric Johnson, and his use of aging Eveready Classic (carbon-zinc) batteries with his Fuzz Face.  Carbon-Zinc age differently than alkaline, and are also constructed differently on the inside.  There is a mistaken impression that the key aspect is reducing the supply voltage.  It's not.  A robust and stable 8 or 7 volts may very well yield interesting sonic flavours, but is not the same as a carbon-zinc battery struggling to provide current.  My sense is that aging carbon-zinc 9V batteries provide an interesting, and relatively unique, dynamic compression to older fuzzes that only draw a little current.  It is a compression resulting from the aging battery's ability to provide a wee bit of current to a gain circuit for a moment before "running out of breath" and needing to "catch its breath" in whatever way carbon-zinc batteries chemically repolarize internally.  As near as I can tell, that dynamic response is a little different from deliberate compression pedals, and would also not occur using such batteries with pedals that draw more current (e.g., 15ma).  The overall result is a function of the idiosyncratic current-delivery characteristics of such batteries within that context.  Outside of those conditions, it's not the same thing.

Again, many musically valid and useful sounds can be elicited from circuits by supplying different V+ levels - lower or higher - as well as providing various fixed limits on current, but there is something a little unique yielded by the combination of older carbon-zinc 9V batteries and low-current germanium fuzzes.  Think of it like an eclipse, where several things have to align to get the final result.

Quote from: Phend on December 29, 2023, 07:05:42 AMI have read that in some effects a battery might sound better than a power supply.
Electrically,
What does a battery induce / do to a circuit.
What could be added to a power supply circuit to mimic a battery.
(I don't believe it is a dieing battery)

The main reason that story is around is the old effects pedals did not bias reliably from unit to unit.  Some were way off, especially where leakage from germaniums stuffed things up.

In this era builders might adjust say the collector (or drain) resistor, or hand select parts so it bias correctly with a 9V supply.  Back in the day people found some pedals sounded when the battery went flat and all that was happening is the low battery voltage was biasing the pedal in a more favorable region.  It was the only way for people without no knowledge of electronics to manipulate the sound.  It's also something people could discover because the battery always went flat at some point.

For example suppose you had a good specimen of a pedal which sounds good with 9V and biased with a collector voltage of 4.5V, about half supply.   Then you have a misbiased example which biased to 3V on the collector voltage with 9V, you could drop the supply voltage to 6V and then it would be biasing to half supply; only imprecise argument here.

The stories of people mustering up "golden" examples of some pedals are ones that probably sounded good with 9V.

There are some circuits which sound different with lower battery voltages and better to some people.  Ideally you would like tweak a 3V pedal and make it sound like a 18V pedal  You expect an 18V pedal is louder but you can attenuate the output to be like the 3V pedal.   However in practice there's a limit to what you can do because the transistor VBE cannot be scaled down by a factor of 6.  It's stuck.   Also the gain of a single stage transistor stage drops with supply voltage.

As Rob said, a V_BE can be from 3% of V_CC (practically insignificant) to 20% of V_CC (seriously considerable)..

I would think the argument for an "improvement" in dynamics would be this degradation, compression. This is guitar. Objectively worse is better. That could be a brand. "Objectively Worse Audio." People pay good money for it!

My power supply is 9.51 volts so I added a 1N914 to get 8.93 into the board.
Still waiting for some 2N404A and 1T308V transistors to experiment with.

Anyway, not on this job, would adding a selector switch with some different diode stacks to change the incoming voltage mimic the so called ded battery ? Of course I have done a bias control to Q2c before but it isn't the same ?? Probably a better way than diodes (showing what I know)

Quote from: Phend on December 29, 2023, 04:03:45 PMMy power supply is 9.51 volts so I added a 1N914 to get 8.93 into the board.
Still waiting for some 2N404A and 1T308V transistors to experiment with.

Anyway, not on this job, would adding a selector switch with some different diode stacks to change the incoming voltage mimic the so called ded battery ? Of course I have done a bias control to Q2c before but it isn't the same ?? Probably a better way than diodes (showing what I know)

New batteries are often 9.5V or so, so you can over do it a bit just going form 9.5V to 9.0V.

The diode droppers work fine for small drops.    If you want to drop to 6V it's not a great solution.  You can build a very simple circuit to make an (unregulated) adjustable power supply.  An old school solution  is something like,



FYI: You can add protection and stuff as well, (need to flip PNP and NPN to be the same as mine.)
https://makingcircuits.com/blog/4-5-v-6-v-9-v-12-v-power-supply-circuit/

Quote from: Rob Strand on December 29, 2023, 04:31:55 PMAn old school solution you can build easy is something like,

I think you've omitted a Base current limiting resistor (for R1 pot set FCW) , Rob..
(either on R1 lug 3 or on wiper..)
It should also serve as part of RC LPF (C multiplied by h_FE + 1) for R1 pot set FCW..

Quote from: antonis on December 29, 2023, 04:54:52 PMI think you've omitted a Base current limiting resistor (for R1 pot set FCW) , Rob..
(either on R1 lug 3 or on wiper..)

All good. I made the pot value just low enough to keep the voltage drops down.  When you connect the PSU to a transistor circuit the load current will be fairly constant so the voltage will be fairly constant.

(FWIW, even diode droppers don't produce constant drop as the diode voltage will increase with load current.)

Objectively Worse Audio New Years sale:

"Just in, Germanium Zeners, found in a warehouse in Allentown PA. at a old semiconductor plant elevator shaft.

Be the first with these on your pedalboard!
The "Ultimate" in harmonic gated compression, which will expand vivid impedance's on the note decay!
Schematics and datasheets included!

Wow, probably won't get any.
And I don't need anymore impotent decay.

Another power supply ?

Quote from: Lino22 on December 29, 2023, 11:38:50 AMHas anybody succeeded in measuring the dying battery impact on the dynamics?

I did a lot of battery measurements and came to the conclusion that battery effects in fuzz pedals is due to the lower voltage of used batteries.

More reading: 9v Battery Impedance

Best regards, Jack