Question about pedal power and supply

[agedhorse]

If they can put phantom power on PA systems why not on bass amps. Then you would not need battery or power supply for active basses or pedals . Just change the jacks. Just thinking.

If you were willing to convert your bass to balanced low impedance output with active electronics, you could certainly do this (with either a 1/4" TRS jack) or with an XLR connector. The problem with doing so is the potential for all kinds of incompatibilities that might cause damage if connected to an incompatible device.

In fact, I have done this very thing on a custom build, P12 power in the amp feeding an all FET balancing and buffering circuit. Pretty slick, but compatible with nothing but his custom rig. The player needed a long cable and this was his choice. At the time, wireless was not going to work for him. His guitars all had 3 pin XLR jacks and looked like hot microphone level signal (would work plugged into a mic input on a console if desired), the amps all had transformer balanced inputs that unbalanced and fed the remaining stock circuitry.

 

[petrus61]

If there is a pedal I wanted, I'd get it whether or not it could run on a battery. I never use batteries in the few pedals I use anymore. I like the option, though it doesn't make any sense to feel that way because I'll never use batteries, can't think of why I ever would.

If the power supply went out, I'd just plug straight into my amp and finish up that way.

I feel the same. If a pedal hits all the right marks, power isn’t going to make or break it by me. Same goes for top mounted jacks, which I tend to find more burdensome for my needs but will accept whichever way the market steers it eventually. All that matters to me is if it does what I need, and does it well without being a PITA. The rest is gravy.

 

[rufus.K]

If you were willing to convert your bass to balanced low impedance output with active electronics, you could certainly do this (with either a 1/4" TRS jack) or with an XLR connector. The problem with doing so is the potential for all kinds of incompatibilities that might cause damage if connected to an incompatible device.

In fact, I have done this very thing on a custom build, P12 power in the amp feeding an all FET balancing and buffering circuit. Pretty slick, but compatible with nothing but his custom rig. The player needed a long cable and this was his choice. At the time, wireless was not going to work for him. His guitars all had 3 pin XLR jacks and looked like hot microphone level signal (would work plugged into a mic input on a console if desired), the amps all had transformer balanced inputs that unbalanced and fed the remaining stock circuitry.

Didn't some Sennheiser mics use P12?

 

[byacey]

Quite a few modern mics will work on as low as 12V phantom; they have a DC to DC converter to provide the high voltage bias for the capsule.

 

[_Some Dude]

I feel the same. If a pedal hits all the right marks, power isn’t going to make or break it by me. Same goes for top mounted jacks, which I tend to find more burdensome for my needs but will accept whichever way the market steers it eventually. All that matters to me is if it does what I need, and does it well without being a PITA. The rest is gravy.

I’ve grown to really dislike top mounted jacks on small MXR sized enclosures, particularly when there’s a 9v input jack mounted on the top too. Makes cable routing a nightmare if you’re using Switchcraft style right angle connectors.

 

[agedhorse]

Many mics do not need or use high polarizing voltages, all it takes is <9V to operate perfectly.

Here's a list that I compiled for a recent product compatibility project (see attachment)

 

[JimmyM]

Listen, you guys have tried to take away my 1/4" speaker cables...don't you dare try to make me have to get used to 3-pin XLR on my basses, too!

 

[byacey]

Most of the AKG mics in the list, C414BULS, C451EB, C460 I am familiar with; these all have converters. The back electret capsules not a true condenser, but are pre-biased with a static charge on the back plate and will work without any polarizing voltage on the capsule, like the old AKG SE series, or the Sony ECM series. Some true condenser mics will work with a very low bias voltage, albeit at the expense of sensitivity.

 

[agedhorse]

Listen, you guys have tried to take away my 1/4" speaker cables...don't you dare try to make me have to get used to 3-pin XLR on my basses, too!

5 pin for you Jimmy... just because... follow the light

(inside joke explained... XLR standards are 3 pin for audio, 4 pin for headsets and 5 pin for DMX lighting BUT even this has been corrupted since the low end lighting market is too cheap to use the 5 pin connectors, they use 3 pin and drop the second or back-up universe or sometimes fixture feedback)

 

[maisbass]

5 pin for you Jimmy... just because... follow the light

(inside joke explained... XLR standards are 3 pin for audio, 4 pin for headsets and 5 pin for DMX lighting BUT even this has been corrupted since the low end lighting market is too cheap to use the 5 pin connectors, they use 3 pin and drop the second or back-up universe or sometimes fixture feedback)

Yup lol! And in the audio world I’ve used 5 pin on Belden 1172a with breakout XLR splits. So right back at those lighting peeps!

It actually comes in handy for long line level runs providing flexibility to choose the breakout I need for the job (xlr, trs).

 

[scotch]

If they can put phantom power on PA systems why not on bass amps. Then you would not need battery or power supply for active basses or pedals . Just change the jacks. Just thinking.

I think EBS did this on one of their amps.

 

[agedhorse]

All the acoustic amps I have designed include phantom power on the balanced input.

 

[seamonkey]

f you were willing to convert your bass to balanced low impedance output with active electronics, you could certainly do this (with either a 1/4" TRS jack) or with an XLR connector.

Maybe it could be a bias voltage over an unbalanced line.
But I do see all the connectors should be changed to something other than 1/4". Something that people understand would be safe to use with bias voltage present. It could be retrofit adapters with blocking caps, and DC out to power the pedals.
Everyone seems to be fine with all the extra power cables so maybe it doesn't matter.

 

[Loring]

Maybe it could be a bias voltage over an unbalanced line.
But I do see all the connectors should be changed to something other than 1/4". Something that people understand would be safe to use with bias voltage present. It could be retrofit adapters with blocking caps, and DC out to power the pedals.
Everyone seems to be fine with all the extra power cables so maybe it doesn't matter.

Not sure you could run enough current though some pedals take up to an amp on their own...

 

[agedhorse]

Not sure you could run enough current though some pedals take up to an amp on their own...

This does add some complexity.

At higher currents, any noise generated on the line by (high frequency) switching components within the pedal would also present a challenge to keeping out of the audio (through inductive or capacitive coupling on an unbalanced line) and even in balanced audio it would have to be rejected by the balanced input receiver (differential amp). In this case, the rejection falls as frequency increases so at even high audio frequencies there might be only 20 or 30% of the rejection available at say 60Hz.

Nothing is as easy in practice as it appears in theory.

 

[delta7fred]

I don't use many pedals (at gigs, at home I have a pedal board) but those I do use are powered with a power supply.

The only things that are battery powered are my tuner and an overdrive pedal that needs 4.5v (3 AA batteries last for years). It would be a PITA on a pedal board because it would need unplugging when not in use.

Our current guitarist was dead against power supplies when I met him in 2003, they added noise he claimed. After running out of batteries one night I offered to make him a power supply, he reluctantly agreed and is still using it.

 

[fauxtoe]

I think that’s right. Talkbass is full of gearheads. We use pedalsboards with power supplies. I would say that, in the real world, at least half of the guitar players and bass players I see in bars are not using power supplies, even if they have pedal boards.

Is it possible you’re just not seeing the power supply? Mine is mounted underneath my board, and most boards I’ve seen in the wild are set up the same way to save a fair amount of real estate up top. Even the Nano size boards can get a power supply of a certain size underneath it.

 

[Leo was right]

Didn't some Sennheiser mics use P12?

Yes.

 

[beans-on-toast]

How about converting string plucking energy into a pedal power generator. Seems that there is a lot of inefficiency related to an amp and speaker cabinet that can be harvested and put to some use.

Thinking out loud....
There’s energy is in vibrating strings.
Pickups and other transducers don’t have a lot of efficiency...yet.
Can heat from an amp be converted to electrical energy.
Can a speaker power micro sized haptic energy generators.
Pedals can be built using very low voltage electronics.

Maybe science fiction....maybe not.

 

[zorf]

Batteries.
Because i dislike teeny flimsy wires and connectors.
because wall warts clog up power strips.
Because it's hard enough finding enough quality AC power in most situations.
i use no pedals when playing bass, maybe one if my amp doesn't have onboard reverb and tremolo when playing other string instruments, but might use up to 6 pedals for solo act.