For the preamp input (and output for that matter), could you guys link me to a reliable pinout for the connectors you recommended? I am trying to create their footprints in Altium because I want to put these connectors onto a PCB.
I cannot, but I withdraw XLR as a good option since I forgot there are 2 standards for wiring those- I dont know on which side of The Atlantic this f up happened 😄 -Go with Jacks. I believe signal plus is center. -The tip pin. And ground is ring.
Cheers!
Cheers!
PCB mount 1/4 phone jacks are rather rare. If you find any at a distributor like newark, digikey, mouser, then there is a link to a datasheet from the manufacturer that will have a picture with dimensions. I mostly handwire such connectors, although it is standard these days to have a screw terminal strip on the input PCB to terminate the wires. Some brands use punchdown blocks for ribbon cable on the pcb, but they are not reliable after a decade or so. Oxygen gets to the spring fork stripping the ribbon cable. Screws holding down wire are forever. Solder is forever.
Quarter phone jacks on input are fine, but 1/4 phone jacks for speaker wires are stupid. Very common though. If the speaker cable gets tripped over on stage, the 1/4 phone plug pulls out partway, shorts the output transistors or IC, and burns it up. If the output cable gets plugged into the input of another amp or preamp, that burns up the input parts of the second amp. So common a problem Peavey installs sacrificial tenth watt resistors in the input wires to blow up something cheap if this happens. Fuses are $2 because of the insurance, tenth watt resistors cost $.01 .
Speakon is the standard speaker output jack these days, although dual banana jacks is about as safe to the output transistors/IC. Speakon has the screw terminals holding down the wires, too.
Quarter phone jacks on input are fine, but 1/4 phone jacks for speaker wires are stupid. Very common though. If the speaker cable gets tripped over on stage, the 1/4 phone plug pulls out partway, shorts the output transistors or IC, and burns it up. If the output cable gets plugged into the input of another amp or preamp, that burns up the input parts of the second amp. So common a problem Peavey installs sacrificial tenth watt resistors in the input wires to blow up something cheap if this happens. Fuses are $2 because of the insurance, tenth watt resistors cost $.01 .
Speakon is the standard speaker output jack these days, although dual banana jacks is about as safe to the output transistors/IC. Speakon has the screw terminals holding down the wires, too.
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@indianajo This was the perfect answer. I will use terminal strips. I assume I will need to wire the phone jack to the terminal strip correct?
I appreciate your assistance as well @Guerilla , thanks for trying to help 🙂
I appreciate your assistance as well @Guerilla , thanks for trying to help 🙂
I like the phoenix pcb strips that solder to the lands on the pcb, and have little screws for holding down the wires from the input jack. I don't make PCB's though, I hand wire the board and use dual screw terminal strips.
The PCB can just have 2 pads for screw terminal.
And if you panel mount the jacks and just run lead wires.
Pretty everyday panel mounts jacks are switchcraft
Usually normally closed " switchjack" which grounds the jack.
So when nothing is plugged in it wont hum. some add inline resistor
10K / 100k dont matter. When something is plugged in it gets disconnected.
Considered normally closed switch. And when plugged in is open.
The PCB neutrik jacks have same thing. 2 contacts on the side for the
switch portion. Then another 2 contacts for Tip / Ring
You can either use the screw terminals for connecting wires to the board.
Or just solder wires directly to the 2 pads on the board.
If you want PCB mount jacks.
Mouser will have mono neutrik 1/4" jacks.
that link is from another store.
Easy to find actually, when I sold guitar pedals
I ordered couple hundred of them from mouser.
And if you panel mount the jacks and just run lead wires.
Pretty everyday panel mounts jacks are switchcraft
Usually normally closed " switchjack" which grounds the jack.
So when nothing is plugged in it wont hum. some add inline resistor
10K / 100k dont matter. When something is plugged in it gets disconnected.
Considered normally closed switch. And when plugged in is open.
The PCB neutrik jacks have same thing. 2 contacts on the side for the
switch portion. Then another 2 contacts for Tip / Ring
You can either use the screw terminals for connecting wires to the board.
Or just solder wires directly to the 2 pads on the board.
If you want PCB mount jacks.
Mouser will have mono neutrik 1/4" jacks.
that link is from another store.
Easy to find actually, when I sold guitar pedals
I ordered couple hundred of them from mouser.
For connectors, use 1/4" jacks, the amplifier input should be the shorting type. This is standard in the industry. Chassis mount jacks are best so you don't break solder joints on the PCB - also standard in the MI trade. Cheaper new stuff often uses PCB mount, but they are careful about mounting.
1/4" patch cables are available everywhere, and are low noise as Markw4 mentioned (good ones that is!).
If you use an XLR, a balanced line will be expected. So, don't do that.
1/4" patch cables are available everywhere, and are low noise as Markw4 mentioned (good ones that is!).
If you use an XLR, a balanced line will be expected. So, don't do that.