Death of the 9V powered pedal as an icon

[Morocotopo]

My guess is that the 9V standard was set by the commercially available batteries back when they became common. When was that? The early sixties?

Also, the standard back then was a few pedals scattered on the floor, none of them too current hungry. Not even a pedalboard! Hendrix, Clapton, etc etc. never had a board at that time. So it was easy to pop them open and replace the battery.  The MXR style box is a hassle to replace the battery once velcroed to a board!
That lasted till... well, the early seventies? Then came what for me is THE best pedal design ever in terms of the box, the Boss pedals. Easy to mount to a board, and with power in jacks. So the power supply started to be more and more common.
Then the digital boxes made their entry, and the current consumption went up, and up, and up... bye bye batteries. Once the batt was out of the question, voltages could raise. and they did, and they did, and they did.
The idea is, I believe, to get more headroom in general, right? Or, in some dirt boxes, to have access to a different sound,whatever that means...

[R.G.]

My guess is that the 9V standard was set by the commercially available batteries back when they became common. When was that? The early sixties?

Your guess is correct. The transistor radio made its appearance in the early-mid sixties in quantity. I had one then. The earliest pedals used germanium transistors with 1.5 and then 3V supplies, corresponding to one and then two carbon-zinc battery cells. The 9V battery originated as a stack of six carbon-zinc cells.

Also, the standard back then was a few pedals scattered on the floor, none of them too current hungry. Not even a pedalboard! Hendrix, Clapton, etc etc. never had a board at that time. So it was easy to pop them open and replace the battery. 

Up until about 1967, a guitarist *might* have one pedal, that being a distortion pedal. I remember buying my first effect - a plug-in-the-guitar Vox Distortion Booster. It was like magic. Before then, guitarists got by with the reverb and tremolo in the amp. The Vox amps with built-in MRB and distortion were semi-magic at the time.

That lasted till... well, the early seventies? Then came what for me is THE best pedal design ever in terms of the box, the Boss pedals. Easy to mount to a board, and with power in jacks. So the power supply started to be more and more common.

The power supply may have existed before the Boss PSA, but it was rare. The Boss PSA set the standard for DC jack size and polarity that still exists today. As an aside, the first Boss power adapters and pedals that used them were not fully thought out and had some warts about the minus side of the supply and switching. I run into this every now and then.

Then the digital boxes made their entry, and the current consumption went up, and up, and up... bye bye batteries.

More importantly, digital logic worked on a 5V standard pioneered by the TTL family of logic. CMOS logic was a later addition by RCA, which only exists as a brand name today. The Radio Corporation of America used to be THE company for all TV broadcasting equipment. Then they died/were bought/etc.

Once the batt was out of the question, voltages could raise. and they did, and they did, and they did.

It's more like they became unstuck from the need for battery compatibility.  Digital went from 5V to 5V and/or 3 to 18V (for CMOS) to 3.3V, 3.0V, 1.8V, 1.5V, and probably lower in the future. By the way, from the view of early 1970s electronics, CMOS was a dark horse candidate for logic. It's mildly astonishing that the incredible rise in logic complexity and integration resulted from customizing CMOS for lower voltages and power levels. It would be literally impossible to cool a modern CPU with 1-2 ... billion... transistors in TTL-style logic. It would create enough heat that even boiling-liquid cooling could not keep up. The relationship of logic voltage/current/power levels to high levels of integration and speed is a whole area of study itself. Look up Moore's Law.

The idea is, I believe, to get more headroom in general, right?

Hmmm. Maybe. Actually, 9V as +/-4.5V peak signals is plenty enough for driving any amp input. I think that the rise of BUMS is what drove a lot of the odd and higher power supply voltages for pedals. It's not widely appreciated that the input of a common tube amp only has a compliance of about +/-1.2V before a nearly-universal 12AX7 grid is cut off or driven into conduction. 4.5V peaks can do that nicely.

It's more likely that a "mod" of connecting up a pedal to +12, +18, +24, +48, 120vac, etc. did something else inside the pedal. Probably just sounding different.

The digital pedals today usually take in either +9Vdc or 9Vac and from that supply a switching regulator to step down to about 3-3.3Vdc for the logic. I regularly see pedals with internal switching stepdown regulators where the designer didn't think to put in protection diodes for the stepdown and it gets fried in the do-anything-for-a-mod pedalboard world.

[Mark Hammer]

Several other current trends portend the death of the 9v-powered pedal.

1) The emergence of multi-voltage power bricks that plan on supplying different polarities, current levels, and supply voltages.  Obviously the market for such bricks is initiated by the pedals that require such diverse supplies, rather than the bricks making such pedals come about.  But the manner in which manufacturers are making use of diverse supply voltages not inconvenient has opened up the doors to such pedals hitting the market.

2) The increasing presence of tiny pedals, fabricated in 1590A boxes (like those from Catalinbread) and that recent series of Mod-Tone mini-trapezoidal boxes, completely eliminate batteries, assuming external powering.  If this were 1976, we'd see pedals in bigger boxes with onboard supplies, like all those big folded steel boxes from EHX, or the Boss CE-1.  But with the migration of line-fed power supplies to outside the pedal (to conserve space and to get the transformer away from the audio path), pedals could become as small as your foot, and commercially available switches could stand.

I might predict little modular boxes with jacks for sending a cable to a central switching station (i.e., controls but no stompswitch), but quite frankly that will all be eclipsed by digital, and things like those iPad-based multi-FX from Digitech.

[Morocotopo]

R.G., so I was not so wrong in the dates. Good.

Mark, true, many new pedals do away with the battery. A good move in my opinion.

The idea of a pedalboard where each pedal has in and out jacks and a power connection and a switch is getting really old. The ideal would be pedals as little modules, not even on the floor, just a foot controller on there with one cable that carries control signals and power. Yes!!!!

Oh wait, that´s already been invented!

Booo.



I don´t think that standard will change in the near future. Old habits die hard, and it would require an agreement between, at least, the bigger companies, sort of what happened with MIDI. Frankly I don´t see that happening...

[birt]

it would be nice to have a stack of 3 cell phone batteries (that would result in about 11V) to power a pedalboard. with a charger that can charge them at the same time.

[R.G.]

it would be nice to have a stack of 3 cell phone batteries (that would result in about 11V) to power a pedalboard. with a charger that can charge them at the same time.

Don't bother. Go get a 12V Lithium-ion powered drill-driver. Cut the handle off the drill for the battery socket and contacts, and mount the amputated drill handle on your pedalboard. Put a 9V regulator under the amputated handle on the pedalboard. Now you can charge one drill-driver battery from the drill charger while you play the other one - for about ten or so hours  - and if you run out, just swap batteries. Takes about five seconds.

[birt]

true, but those batteries cost a lot more. (if you want a good one...)

[Jdansti]

I used to have a Braun electric razor that would run on any power supplied to its two prongs from 12V to 220V, AC or DC, and regardless of polarity. I wish I could do that with my pedals. It would be great if there were a little brick or chip that would do this, perhaps with a couple of DIP switches on it to set the output voltage (or by connecting different pins if it were a chip).  Of course, electric razors are not picky about how clean their power is, but I imagine that the output voltage could be cleaned up for pedal use.

[R.G.]

I used to have a Braun electric razor that would run on any power supplied to its two prongs from 12V to 220V, AC or DC, and regardless of polarity. I wish I could do that with my pedals. It would be great if there were a little brick or chip that would do this,

I don't know about getting down to 12V, but there is at least one little brick I know of that runs from about 80V to 240V, AC or DC, polarity insensitive, and puts out a very quiet and clean 9.5Vdc.

[Vallhagen]

One concern that i discoverred early, when i accidently ran into this whole DIYbox thing some 8 month ago, was to find a "standard plug" for a bipolar supply (as well as the standard bipolar supply/wallwart itself). Some 3-way thingy that was almost as common as the 2.1mm plug we all know. Where is that?

We choose to place switched power converters in every box instead... Silly.

With so many bipolar designs out there, there really should be one. Because... there is none, right? Or have i missed it?

[R.G.]

One concern that i discoverred early, when i accidently ran into this whole DIYbox thing some 8 month ago, was to find a "standard plug" for a bipolar supply (as well as the standard bipolar supply/wallwart itself). Some 3-way thingy that was almost as common as the 2.1mm plug we all know. Where is that?

DIN plugs/sockets. Available in 4, 5, 6, 7, maybe more contacts.

We choose to place switched power converters in every box instead... Silly.

Not silly. Just a logical least-effort fallout of the history of 9V batteries and the Boss PSA power adapter. 

[Jdansti]

I think these are what R. G. is referring to. I've used these when I need more than two conductors.

[R.G.]

That's the animal!

[PRR]

> there is at least one little brick I know of that runs from about 80V to 240V, AC or DC, polarity insensitive, and puts out a very quiet and clean 9.5Vdc.

"One"? Whatever. My world is full of little bricks. They just show-up. One I found in the outside outlet (someone's lost cellfone charger) is "100V-240V~". It may be marked for AC, but the way many of these work, DC would be fine. Found two more "100V-240V".

> We choose to place switched power converters in every box instead... Silly.

For just one, yes, annoying. But when you make millions, a small detail. Every cellfone, MP3 player, and netbook/tablet PC runs on voltage conversion. The chip-makers push a wide variety of buzzers to make saggy battery into multiple regulated DCs.

> DIN plugs

Bulky, and not stomp-proof. Acceptable on external hard-drive boxes which seem to use one of several 4-pin connectors mostly not the "MIDI" DIN.

Anything other than coaxial can only go in one way. On a dim stage, that can be frustrating. I have to carry my cell charger over to the light just to see which way is up.

We can use batts but optimize circuits for 6-month operating life. Thrifty design. I used to have microphones that ran non-stop for years on one AA. (But "progress" has been going the other way.)

We can run full 120V/20A or 230V/13A power to every pedal. But bringing potentially 2400 Watts to 1 Watt pedals means unnecessarily large/rugged connectors, plus the fun of 50/60Hz at hundreds of times our signal level.

We could invent a smaller power-distribution scheme allowing smaller connectors and less 50/60 trouble. The obvious one today IS the multiple-9VDC box. 9V converts-down to 5V/3V E-Z, up to 18V or 48V without major drama.

The other "obvious" answer is _USB_. Chargers and Powered Hubs sell millions more than pedalboard supplies. I have a "sick" USB 7-port hub here which will charge/power even though it garbles data. GoodWill, yard-sales, etc will turn up more (except warts and hubs are soon separated). USB power is non-trivial: I have three _scanners_ which whirrr and moan a motor with only USB power. Fine analog pedals can be made to work on 5V. The old 7V-min chips all have 3V-12V replacements. As a side-frill, for another buck the "audio in/out" could be put on the USB, and then patching switching and sound-scene choices can be digital.

We live in interesting times.

[LucifersTrip]

can you imagine how many DIY electrocutions there would be if we were "experimenting" with and "tweaking" 120v pedals....

[R.G.]

> there is at least one little brick I know of that runs from about 80V to 240V, AC or DC, polarity insensitive, and puts out a very quiet and clean 9.5Vdc.

"One"? Whatever. My world is full of little bricks. They just show-up. One I found in the outside outlet (someone's lost cellfone charger) is "100V-240V~". It may be marked for AC, but the way many of these work, DC would be fine. Found two more "100V-240V".

I see the irony wasn't lost.   

[Ronan]

The irony was not lost...

A good connector for power supplies other than the standard 9V is these connectors often used for CB microphones in the past. Available in 2-pin/3-pin/4-pin and maybe more, they are cheap and robust, and have a threaded metal locking ring that prevents the plug from coming adrift once connected. I have used them for powering custom equipment at work. Here's a pic:

http://www.ioffer.com/i/100x-4pin-male-female-panel-chassis-connector-kit-c146-198282956

Another possibility for bipolar supplies is using a voltage doubler inside the pedal, however the caps need to be fairly large (in value and size). By using a doubler you only need a single phase input (2 wires), and there's a few cheap AC wall warts out there for alarm systems or other systems that can be used. It is getting increasingly difficult to buy a wall wart with an actual real transformer inside it though, the switch-mode DC supplies out of China are so cheap these days, and are replacing the wall warts with real transformers at a very fast rate.

The pic below is an example of a voltage doubler inside a wah enclosure, giving +/-15V regulated supplies using TO-92 size LM317/337, the power supply is on the far right hand side of the vero.

[garcho]

Standards are convenient for everyone:

Consumers - makes purchasing 'new' things less risky

Manufacturers - streamlines production

Sellers - makes communication easier

Designers - makes prototyping cheaper, quicker

I don't care what the standard is, as long as there is one (or two, damn Imperial system).

[tubegeek]

A good connector for power supplies other than the standard 9V is these connectors often used for CB microphones in the past. Available in 2-pin/3-pin/4-pin and maybe more, they are cheap and robust, and have a threaded metal locking ring that prevents the plug from coming adrift once connected. I have used them for powering custom equipment at work. Here's a pic:

http://www.ioffer.com/i/100x-4pin-male-female-panel-chassis-connector-kit-c146-198282956

THANKYOUTHANKYOUTHANKYOU Ronan!!!

You wouldn't happen to have bought 100 of these and only need 70 or 80 by any chance? I'd love to have 20 or so of these to mess around with.
[edit] nevermind, I just saw the sidebar where they sell them in 10s.

They look to me like they'd be safe to use with ground, filament, and B+ for tube circuits, provided the heatshrinking was done neatly. And arguably nicer, and MUCH cheaper than the Amphenol stuff.

Any opinions from the peanut gallery?

It is getting increasingly difficult to buy a wall wart with an actual real transformer inside it though, the switch-mode DC supplies out of China are so cheap these days, and are replacing the wall warts with real transformers at a very fast rate.

Truth.

[Ronan]

datasheet - http://www.philmore-datak.com/mc/Page%2054.pdf

Insulation resistance is stated as 500V DC 100Mohm, contacts 5milliohm at 1A DC. My peanut gallery input

Edit: the distance between the pins on the 4-pin socket appears to be 1.5mm (60 thou) from the datasheet. I don't the DC voltage value required to arc between the contacts...