Test Bench.
My basic test bench, consisting of a Hitachi dual beam 'scope, a digital multimeter, 2 banks of 8Ω power resistors and my precious Hewlett Packard 3310A analogue function generator. Here, I'm doing a test run on one of my 300B SET amps after a major modification. JJs are in situ.
Not forgetting my pair of close-up specs (age, you know).
My basic test bench, consisting of a Hitachi dual beam 'scope, a digital multimeter, 2 banks of 8Ω power resistors and my precious Hewlett Packard 3310A analogue function generator. Here, I'm doing a test run on one of my 300B SET amps after a major modification. JJs are in situ.
Not forgetting my pair of close-up specs (age, you know).
Attachments
Thanks,
It's a very nice sounding amp and powerful enough (5W) for my needs.
I like it more than my SE EL34.
Stax Amplifier
I built this amplifier for my Stax headphones: All-Triode Direct-Drive Tube Amps for Electrostatic and Electret Headphones. – HeadWize Memorial
I made a choke input power supply with a vacuum tube bridge using four PY81 (hidden under the tube cage). Soviet mica capacitors for coupling and polypropylene in oil as output capacitors.
I built this amplifier for my Stax headphones: All-Triode Direct-Drive Tube Amps for Electrostatic and Electret Headphones. – HeadWize Memorial
I made a choke input power supply with a vacuum tube bridge using four PY81 (hidden under the tube cage). Soviet mica capacitors for coupling and polypropylene in oil as output capacitors.
Attachments
Now, that's really nice inside and out. One suggestion though: why not put a couple of cable-ties on the bundle of wires running underneath at the centre?
Rustic Tubes.
This pre-Amp is somewhat similar in appearance to all my other tube amps - a standard Hammond chassis, and Irish Red Deal wooden sides. It uses the JJ and Electro Harmonix twin triodes, and the 12X4 auto radio vibrator HT rectifier. Bass and Treble Eqs have a range of +/- 12dBs.
This pre-Amp is somewhat similar in appearance to all my other tube amps - a standard Hammond chassis, and Irish Red Deal wooden sides. It uses the JJ and Electro Harmonix twin triodes, and the 12X4 auto radio vibrator HT rectifier. Bass and Treble Eqs have a range of +/- 12dBs.
Attachments
Last edited:
I'll subscribe to that Here just finish a sustainable tube amplifier, local bamboo and acacia wood for the chassis, EL84 on parallel with ECC81 as driver and 6N2P as tone stack. Original idea from Alex Kitic but on the initial test on breadboard some adjustment and changes has been done from the original schematic. The two channels are independent with two stabilised SS power supply fixes at 315 Vdc powered by Antek toroidal and plate to plate feedback.
7.9 watts before clipping, impressive OPT from China manufacturer very responsive on low freq.
Sound? Very good to my ears, punching and warm low freq. and very balanced and detailed mid/hight.
All the best to everybody.
7.9 watts before clipping, impressive OPT from China manufacturer very responsive on low freq.
Sound? Very good to my ears, punching and warm low freq. and very balanced and detailed mid/hight.
All the best to everybody.
Attachments
Hi all
I just finish my pre amp, this is my first tube experiment and luckily it worked out well for me, the only thing is that the preamplifier has more gain than I expected but sounds very good
IMG_6972.HEIC - Google Drive
Img
It was fun to build it
I just finish my pre amp, this is my first tube experiment and luckily it worked out well for me, the only thing is that the preamplifier has more gain than I expected but sounds very good
IMG_6972.HEIC - Google Drive
Img
It was fun to build it
Hi Carlp, thanks for the tip!!!
Attachments
