Necrobump! Six or eight months ago i ignorantly bought one of these from the local freight salvage dealer for about $28. I'm gonna go out on a limb and suggest that the opa2134 chips in the photo were fake, but mine came with a socketed ne5532 and a pair of surface-mount tl062 in the...

Pull 'em out and measure the resistance between pins 4 and 5.

Mosfets do blow, and they often blow as a dead short. If you have a component tester, you should be able to test it. Other than that, maybe post pictures of the boards from multiple angles, perhaps something is installed wrong.

With no power connected, can you measure resistance between the two red primaries?

What in the heck do you mean by "twisted red wire goes to ground" - where do those wires come from? You sure none of the wires coming out of the transformer are damaged?

Red-yellow should be literally ground. It's the center tap between the two red secondary wires. So, double-check how the transformer is connected to the power supply board. Maybe post pics. And make sure there's nothing shorting some pins on the bottom of the board.

Yeah, you need a power source to generate the high voltage. And you'd have to build it yourself or pay someone to do it. Spritzer briefly sold an srd-7 pro board. I have an unfinished design that i may revisit but since i don't have a lot of high-bias stats it's not a priority. Another problem...

Necrobump just to say that I picked up a gimpy pair from ebay on a whim. No pads, damaged plug. Threw on Geekria pads and put a new plug on the cable. The 4-pole plugs sure are fiddly to solder by hand but I had it sorted in about 20 minutes. I'll make it permanent as soon as I figure out...

I feel like the quantity is fine, but the quality, surprisingly enough, isn't as good as I'd expect for $35.

After spending significantly more time with my CCA C12 I've come to the conclusion that the bass just isn't up to my standards. I like bass that goes low but is tight and clearly defined. I accept the slightly bass-lean signature of single-armature etymotics and sometimes goose 'em with EQ...

Those of you who recognize my avatar know i have a bad habit of buying broken headphones. So i pulled the trigger on a "right side not working" M300, pretty complete set, $40ish shipped. These really are a half-baked design, if that. But anyway. Construction method is glue. Cyanoacrylate...

It's popular in my generation (gen-x) to say that good hip-hop died in the 90's. And yeah, once upon a time i was a white boy in the burbs listening to Run DMC. Commercial hip-hop really has gone some pretty horrible places over the last 30 years, but i discovered a couple-three years ago...

They turned up today. I'd take pictures but they look exactly as advertised. Like a K500 driver (like a K400 driver but shiny) Exact fit in the spare K400 frame as predicted. Have not listened to them yet.

fwiw, the xl4005 step-down modules i tried to use to power 12v fans and a meter of LED strip (about an amp? on a module rated for 5 amps or something silly?) from a 24v supply literally exploded. Switching converters under load tend to be pretty noisy, and that noise is hard to get rid of.

The klipsch hp3 link seems to have gotten mangled? I have some of the 40mm "composite mycelium of carbon" drivers (sometimes described as wool composite maybe?) and they look an awful lot like the biocellulose drivers i pulled out of the Aurvana Live (AH-D1001?) that i never ever listen to...

ok i pulled the trigger. I guess in 2 months when it gets here and i transplant it into the empty K400 frame I will let you know how they are. Maybe even set up my measurement rig and do some comparisons. I guess in the mean time i should design and print some oval "K ???" badges. And a set...

There's a product watchmakers and jewelers use called "hypo cement" which is basically like e9000 with a needle applicator already on the tube. It's not expensive. You'll want to degrease the surfaces first. Alcohol will work well if you got it.

I was poking around the aliexpress driver selection and came across these: https://www.aliexpress.com/item/32543482390.html?spm=a2g0s.8937460.0.0.d3ef2e0eUx1CME Which are clearly in the style of drivers that started with the K400 and continued through at least K702, though with an earlier...

I would have to assume that one or more solder joints are sub-par. Did you apply any solder flux? I heartily recommend kester flux pens. https://www.amazon.com/Kester83-1000-0951-Soldering-Flux-Low-Solids-No-Clean/dp/B004X4KOWS

Old thread, but I'd be remiss if i didn't point out that these are 50mm: https://www.parts-express.com/peerless-hpd-50n25pr00-32-2-headphone-driver-diaphragm--264-1510 I bought a pair thinking i would retrofit them into the Presonus HD-7 i picked up for <$10, which are identical to the...

I sort of got distracted slash lost interest? I am unsure of my design, and it needs at least one more revision. In order to really measure the bias voltage, I need a high impedance probe, and I bought a 1-gigaohm resistor from mouser for that purpose, but I still need to design and print an...

Actually, the *right channel on this k400 has an issue, so i guess I will commence exploratory surgery some time this weekend