Leaderboard

So just an update re. my 009 problems. Sent back to Stax, huge respect to them for the turn around time. Received back today as new, working perfectly with my superb Mjolnir KGSShv Carbon. I'm back to where I want to be.

I checked my parts bin. The black Phoenix 651-54522548 has open bottom. interestingly, my green, Phoenix 651-1935174, which is rated at 400VDC, has the covered bottom. Maybe this should be the "official" Stax Mafia endorsed terminal block for B+ and B-?

Speedy back on its way. It was dried out, a small amount of rust was removed, it was timed and regulated, and the waterproofing issue has been addressed.

The Hoffman forums obviously aren't frequented by gay men!

I lack the "won't" of a teetotaller.

I bought my stands a few years ago from there guys: http://timbernation.com/speakerstand.html - pretty good pricing and they do custom sizes

Good, that must be a relief.

^this, given some of the generous amounts of solder used in other areas shown in the pics. The excess solder sits on the trace and the mask eventually breaks down...

you lack the will of the warrior

Most insane thing I've ever seen! The traffic driving back to the east coast from TN was sick too...10hr drive turned to 16hrs...and I had to work today.

I'm listening to my BH right now. The offset drift a bit and you have to wait a few minutes until it stays low and stays stable. All the measurements seem correct. It run hot, very hot, very very hot....

A couple things. Put simply, a choke is an inductor and an electrostatic headphone looks kind of like a capacitor. Look in any electronics textbook and you will see that when you connect an inductor with a capacitor you get a resonant circuit, which means you can have a peak in the frequency response at the resonance frequency. I said the headphone looks “kind of” like a capacitor. It doesn’t exactly resemble a capacitor because it makes sound, which means it uses power. The power spectrum of music is highest in the mid-bass to lower mid-range areas (approximately 50-300 Hz). The impedance of a choke rises with frequency, which means that it requires more current to drive it at low frequencies, exactly where the headphone is requiring the most current and voltage to make music. This increases the distortion of the output device. The largest commercial plate choke I have found runs around 200H. This has an impedance around 25 kilohms at 20 Hz, rising linearly with frequency from there so at 40 Hz its impedance is 50 kHz, which is a typical resistance for a stat amp plate resistor. So at the lowest bass frequencies it requires/diverts more current from the headphone than a typical plate resistor. This is all based on an ideal choke, ignoring the possible resonances and other imperfections of a real world device. With a resistor load, you don't have the possibility of a peak in the frequency response but the resistor requires curent to drive it through the whole frequency spectrum. In fact, with a resistor load, the amplifier actually wastes more current (and power) driving the resistor than driving the headphone. By comparison a really good current source load demands a negligible amount of current, which means all the standing current of the output device is available to drive the headphones, which is what you want. As I said elsewhere, it converts an amp for driving output resistors to an amp for driving headphones. It is simply a better technology. This is why Stax has used current source loads in its solid state amps in place of resistor loads since the 1970s.

Root canal for a cracked tooth.