Is that a Brown Dog adapter I see there? Was it very difficult and/or time consuming to solder the SMT part onto it? -b

I think the Blackgates should do wonderfully. Of course, they will take an eternity to break-in and one problem is that they need to stay broken in. If I recall correctly, the impedance of those ribbon transducers was awfully low.. something on the order of 2-3 ohms correct? If that's the...

My two cents on the matters.. I've never had a problem with Mouser. They always ship my stuff on the same day and without fail I get it two days later. The same with Digi-key. Yesterday I actually got a package overnight even though it was shipped standard UPS ground. _That's service._...

The 'internal shield' on the 6DJ8 should be grounded to provide some isoluation between each triode in the tube. As far as the hum issue goes, this has been discussed on headwize as well. I'm not sure what the resolution was -- it might just be that the optimized circuit is more prone to hum...

You can buy them direct from http://www.lundahl.se. Either that, or contact one of the US distributors they have listed on their website. b

Kits are often the way to go if you don't feel you have the expertise to do it yourself directly from a schematic. I really like my Earmax clone amp. It cost me about $100 in parts and $15 in alcohol to build. The project is well documented and can be found at HeadWize...

It's not really a "theory" is it? If you look at the Thiel-Small equations, you have that the sensitivity of speakers being determined by a number of parameters, one of which is Sd, or radiating area. However, the sensitivity is proportional to the square of Sd, but only linear with respect to...

Avatar contest? I probably wasn't registered then. I built an MTM out of some PVC tubing but it was exceptionally bright. I decided to replace it with a tall PVC transmission line with two full range drivers in each. Once I can find more of the 40-1041 5" full range Radioshack drivers, I'll...

Have any of you considered a dual d'Appolito in a single enclosure? I was thinking of maybe MTMWMTM, although the configuration on the actual speaker may vary. I was looking at an ubercheap 84dB/1W/1m mid. If you wired them in parallel/series pairs, then you'd get about 90dB/1W/1m from those...

The fact that nuvistors are so rare means it will be very difficult to get much hope at building any amps with them. Steve Bench discussed on his website some low-voltage tubes that had been used in virtual antiquity for early hearing-aid amplifiers. It's been a while since I've looked at the...

Quote: "Quite honestly, I'm convinced that it would be a shame not to turn the unit into an autonomous preamp because it has the potential to be a giant-killer. Low-mu power triodes, running at only a tiny fraction of their maximum ratings, fed by a soft start, pi-filtered, tube-rectified...

I don't think oil should be condemned completely. Jensen makes a bunch of paper-in-oil/copper-in-oil and other capacitors that are considered top of the line (they should be considering the cost of some..) Granted, I'm sure it's up to one's preference. I don't want to make this a separate...

I wouldn't say in the 470uF range that your only option is electrolytic. Your only _sane_ option is electrolytic, but there are still alternatives. Solen makes very high values of their fast caps. Even http://www.partsexpress.com holds values up to 200uF/450V. By running a couple in parallel...

As far as the impedence of the phones, you shouldn't have much trouble between 120 and 300 ohms. I think the biggest difference would be between, say, some 600 ohm HD-545's and some 32 ohm Grados. As for the output capacitor, its primary purpose (I would imagine) is to lower the overall...

Air-tight versus not-air-tight? :B Wouldn't a non-air-tight connection just..slip out? b