CindyJarvis

I am no Klipsch speaker expert but here is what I would instead of carrying a speaker to another place. Dince the schematic shows the + input connected to the + of the driver. Take a 9 volt battery and while watching the woofer connect the battery to the leads coming from the woofer briefly. The woofer will be pushed out if phase is correct, it will pull in if incorrect. So again if the speaker pushes out make note which wire is connected to the battery positive and thats your woofer positive. -Cindy

Hello Maynard, I want to say I think it is a great thing you are doing. I like the DIY nature of your threads, you aren't trying to sell anyone anything and it is such a breath of fresh air. I hope I wont be too much of a bother if I ask you a few questions. It looks like you use a separate volume control for each channel? What is the reason for the deviation from a standard stereo pot? Now a couple power supply questions. I am used to seeing many more filters in power supplies. In your experience have you found that tube related equipment doesn't benefit from said filters? I am thinking todays digital logic circuits require more care in regard to noise reduction. -Cindy

Hello, I found this forum through a google search about tube amps and klipsch speakers. My background is a B.S. in Mathematics. I also worked alongside some very bright engineers for my uncles corporation designing power supplies. I happen to have a passion for music like my mother. -Cindy

Another benefit along with reduced cost is better high frequency range. When you use more turns to increase the primary inductance the downside is increased shunt capacitance which limits high frequency response. Designing transformers is a tradeoff. When you eliminate the low frequency response as a requirement you can have better high frequency response. -Cindy

You wouldn't necessarily get more mid band power. The real advantage is you can get away with much smaller output iron. When you airgap a transformer which is necessary when standing DC current is passing through the winding the inductance drops off. To compensate for a lower L output transformer designers use more turns to increase L. More turns means more copper and iron and this is why a 20-20k output transformer for SE tube amps are so expensive. -Cindy

The Russian 6P14P-EV is a good substitute for the 7189. Do not try and use a standard EL84 or 6BQ5 in these amps FWIW. -Cindy

How fast do you have to go to flip a car? I would bet she was going a little too fast for roads that are covered by a sheet of ice. I have seen another car flip years back but that was at highway speeds, 60-70mph. I don't want to hear any "female driver" jokes please -Cindy

Directly in front of my house at 6:30am. The Lady driving was okay but a little shaken up. She was on her way to work and swerved to avoid another car. I live in the woods and it took about 20 minutes for help to arrive, good thing she seems okay. -Cindy

They are only 30 watts because they are Class A amplifiers. The self inverting output stage only works for class A operation is my thought. -Cindy

Hello everyone I am new to the forum here :^) Wouldn't testing an amplifier with square waves at 20kHz not give a good indication of it's response at 20kHz? That would be testing far above what an audio transformer is designed for, really you are starting to get into the upper frequency region (>200kHz) where the transformer designers place the resonant peak. -Cindy