Yes, I agree. Inside the Y-splitter would be my preference as well.

Thanks for finding these schematics. The top image of a P-S-B switchable adapter looks like it was designed to be used with an existing 4P cable, however the 'B' circuit shown uses only a capacitor (680 nF) rather than a series resistor and capacitor in parallel with the 73 ohm resistor. That...

Yes, it seems like this might also work. Maybe time to play around with some analog circuit simulation.

Yes, my understanding is that the ER-4P cable has a built-in 27-ohm resistor while the P-to-S adapter adds another 75 ohms in series to make it equivalent to the 100 ohms resistance in the 4S cable. Based on the Etymotic patent, it appears the original 4B filter network is a 100 ohm series...

I've checked the usual places and can only find P-to-S adapter cables.

Does anyone know where I might find an adapter/converter to convert an ER-4P into an ER-4B?

Yes.  I'm using a Power Bright VC100J transformer.  (And I did check even that to be sure it was actually providing ~100 Vac.)

SRM-323s failure   Just wondering if anyone else has experienced a bad 323s?  I recently bought one from PriceJapan and it seemed to work okay the first couple of times I tried it but soon starting cutting out in the right channel after a few minutes of use.   I measured the DC voltage on...

Quote: I have this window that pops up when connected to the internet via dial up. It says svchost.exe has generated errors and a log will be generated. I had this same thing happen, and it turned out to be a symptom of being infected by the msblaster virus. You can check this by...

Quote: Very few opamps have constant open loop gain in whole audio range. AD8610 is the only I know of Aos, are you sure about this? I looked at the AD8610's datasheet, and while it doesn't specifically show the open-loop gain over the audio range, it otherwise doesn't seem to suggest...

Quote: On the minus supply opamp a .1 [uF] from pin 2 to ground is almost always necessary. I experienced oscillation in the minus supply opamp after I tried adding some small local decoupling capacitors to the main amplifier board. The supply returned to normal after I removed the...

Quote: the 66 IS either a 63 or 56 , just that the package is an OEM part According to icmaster.com (an online IC parts search database) these are all separate Burr Brown (now TI) parts. The PCM56 and PCM66 are listed as 16-bit devices, with power dissipations of 260 mW and 50 mW...

Quote: i would have guessed the prehead would have enough power to drive the akg1000? With a maximum output of 13 V at 800 mA, the PREHEAD shouldn't have any problem driving the AKG-1000s.

Quote: A max output of only 5mW at 16 ohms?? Man, is that low! And, like redshifter said, it will be half of that or slightly less for 32 ohms. This is only true if you assume that the given power rating reflects both the player's maximum current and maximum voltage output...

Quote: I have quite a lot of Sony kit and without exception, the sound from their headphone sockets are quite dire. It's certainly true that the sound from the headphone outputs on most equipment is unlikely to meet with the approval of discriminating audiophiles. However, while I...

Quote: My Sony SCD XB-940QS has a maximum output level of 10mW on the headphone jack at an load impedance of 32ohms. The Sennheiser HD-600 I want to buy has an nomial impedance of 300ohms and a power handling capability of 200mW. Won't both things work together? They will work...

Quote: tho audio-t are selling the hd600's for £170 at the moment compared with their normal price of £300...hence why i was considering them so strongly. shame my amp aint up to the job Kathy, the headphone output on your Sony ES component is most likely rated for 10 mW at 32 ohms...

Quote: But does this circuit yield the equivalent of an output with impedance < 2 ohms in terms of damping factor? Yes, by definition. Quote: I'm especially worried that there seems to be an easy path for back-EMF to travel, in a loop around the 2 ohm resistor? The "easy...

Quote: Regular power amplifiers for magnetic voice coil systems are generally trans-addmittance stages (i.e. Voltage to Current devices) and therefore have a relatively high output impedance. Actually, most power amplifiers are designed to act as voltage sources (not current sources)...

Quote: Have you measured how much power it'll put into a 120 ohm load? It sounds like it certainly could power the K1000s... I've ordered a kit from antness and that's exactly what I intend to use it for. As is, it looks as if it should be able to deliver about 300 mW into 120 Ohms...

Quote: Would it be possible to power the K1000's from an RKV Mk II (3 watts per side) at moderate volume with acoustic jazz and achieve satisfactory results? The maximum power rating for the K1000 is about 1 W, so any amplifier that can deliver this much or more power into the K1000's...

Yes, I was able to view the ZIP file without problems. Once unzipped it's a WMF file, which can be viewed in Microsoft Word by clicking on "Insert"-->"Picture"-->"From File." It is clear at full screen size when viewed at 150% or 200% magnification.

This buffer is just about perfect for my home system needs. Thanks ppl. Is anyone considering making a board for this design?

the majority of high impedance cans are also rather low in sensitivity, so they require far more current and voltage than the typical portable sound device can produce. Actually, the Sennheiser HD600 (300 ohm) seems to have about the same sensitivity as most of the Grados (32 ohm)--97 dB at 1...

The following two books are excellent, although they are written from an objectivist ("the lower the distortion, the better the amplifier") point of view: "Audio Power Amplifier Design Handbook" By Douglas Self (ISBN: 075064527X) "High-Power Audio Amplifier Construction Manual" By G...