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wdecho

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On ‎12‎/‎3‎/‎2017 at 9:06 PM, DizRotus said:

 

20171203_201048 (Medium).jpg

20171203_201315 (Medium).jpg

 

 

Lamp cord used for XLR cabling is a total fail.

 

My error and apologies.

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Lamp cord is not used for XLR cabling.  The balanced connection is between the Pono player and the amp using shielded balanced cabling.  The "lamp cord" connects the amp to the speakers.

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5 hours ago, DizRotus said:

Lamp cord is not used for XLR cabling.  The balanced connection is between the Pono player and the amp using shielded balanced cabling.  The "lamp cord" connects the amp to the speakers.

 

The photo had myself scratching my head as well. I was looking at the rear XLR jacks and wondering why there was only two leads going to them. (then it occurred that they were speaker output)

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yeah, I figured that out after I noticed separate RCA cables used for both the inverting and non-inverting inputs.

 

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I was forced to use “lamp cord” to connect the amp to the speakers because I don’t have enough coat hangers. @BEC

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15 hours ago, DizRotus said:

I was forced to use “lamp cord” to connect the amp to the speakers because I don’t have enough coat hangers. @BEC

 

What else do you call it?  Does it really have another name?

 

Google lamp cord and what pops up, two conductor wire.

 

BTW, FWIW I like lamp cord.  Anything else is money wasted.

 

 

 

lamp_cord.jpg

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I believe it is also commonly referred to as zip cord.  If it was good enough for PWK?

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Nope - GW's teeth were not made of wood but Ben Franklin ushered in the use of lamp cord by attaching it to his kite. True story. 

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Nelson Pass ran some test of speaker wire and said yes the expensive ones were slightly better. He also stated he uses Fry's 18 gauge copper wire himself. The saying among many is do not spend more on wire than you did on your amplifier. 

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On ‎12‎/‎7‎/‎2017 at 3:59 AM, wdecho said:

The saying among many is do not spend more on wire than you did on your amplifier.

 

No need for the 10 AWG garden hose using the delicate triode tube amplifier.

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I had some outer cases from some Knight mono PP integrated tube amplifiers that are EOL. Seemed a good choice for a PS case and external case for the TI 3255 amplifier.

Kind of a mild space age test gear look...

 

I refinished them in Cobalt blue, and cut front and back panels out of 1/8" aluminum sheet. Picked up binding posts, RCA jacks, and the umbilical DC power cord parts from Mouser.

Found some purple panel mount 12 volt DC LEDs from eBay. I'm using the 12 volt AC winding from the Antek PS transformer, and built a regulated 12 volt DC supply using a LM317 voltage regulator and other scrounged up parts.

 

I wanted to run the power for the LED with the case that the amp is housed in, through the same cord with the amplifier B+/B-. But they are only three conductor jacks/plugs, so I'll have to purchase jacks/plugs to run power to the LED housed with the amplifier.

 

They have their imperfections, and I still would like to do a couple more things, but for now they look better than an amplifier and power supply mounted to wood.

DSCN2666.JPG

DSCN2667.JPG

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9 hours ago, mike stehr said:

I really need to get power to the other LED.

DSCN2672.JPG

Cheap wall DC switcher probably the simplest, cheapest solution mounted inside if there is room.  

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7 hours ago, wdecho said:

Cheap wall DC switcher probably the simplest, cheapest solution mounted inside if there is room.  

 

That's not a bad idea, and a wall wart would tuck inside the case with the amplifier. But one would still have drill a hole through the back panel for access, with one more plug to plug in a wall outlet.

I cobbled up a regulated supply out of Radio Shack strip-board, used diodes for a fullwave bridge, with a 3300uf filter cap. I used a LM317T regulator, with a 100 volt 0.1uf polyprop for the input voltage pin, with a 10uF cap on the voltage out pin. I scrounged a heatsink for the regulator from a scrapped Fisher multidisc CD player, and mounted the reg with heatsink compound.

 

With the calculated resistance for 12 volts DC out, the supply puts out 11.50 volts DC, and seems to run both LED panel lights with no problems.

The supply for the LEDs is mounted in the PS case. I may as well just order two plugs, and two jacks, then drill a couple more holes in the back panels, and run a wire to each jack.

 

If I paid more attention, I should have spent a bit more and purchased plugs and jacks with multi-pin conductors. That way, I could have ran the 49-50 volts B+ for the amplifier, and also 12 volts DC for the LED panel light. Containing everything in one plug...

 

I should still drill holes on the back amplifier case panel, to mount the female XLR jacks for configuring differential input. So drilling more holes isn't that big of a deal, and I would like to somehow have all the panels anodized blue.

 

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4 hours ago, mike stehr said:

 

That's not a bad idea, and a wall wart would tuck inside the case with the amplifier. But one would still have drill a hole through the back panel for access, with one more plug to plug in a wall outlet.

I sometime just put the plug inside and solder to the pins that plug into the wall and wire to the IEC connector. No more holes to drill. 

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