alexberger
Responses from alexberger
| 300b lovers Hi @atmasphere , The bottom end is predictable. ~8K 6sn7 (260v, 9mA) internal impedance and 70-80H transformer primary inductance gives -3db around 20Hz. Actually I measured -2.37dB at 20Hz and -3.62 at 15Hz. According to plate voltage-current c... | |
| BEST little know Jazz Album that you ever heard? Stan Getz Quartet At Large | |
| Amplifier Pairing with Coherent 15s Hi @mmcgill829 , What are your impressions from Coherent 15 speakers? | |
| 300b lovers I continued tuning my amplifier for the Hashimoto A-107 interstage transformer (IT). I changed the load resistor from 57K to 39K Ohm. The difference in square wave overshoot is very small, but frequency response peak is just +0.5dB instead of +1.... | |
| New Vinyl Jazz and Classical Reissues Dexter Gordon & Slide Hampton– A Day In Copenhagen "You Don't Know What Love Is" Reforest The Legend https://youtu.be/d-VLMgC37tI | |
| New Vinyl Jazz and Classical Reissues Mal Waldron With Jackie McLean, John Coltrane,... – Mal/2 - Original Jazz Classics https://youtu.be/X8AxJ0BOBl8 | |
| New Vinyl Jazz and Classical Reissues Thelonious Monk With John Coltrane - Original Jazz Classics - "Off Minor" https://youtu.be/6-zvpHOfkiQ | |
| Classical Vinyl Series Ella Fitzgerald Sings Songs From Let No Man Write My Epitaph - "Black Coffee" https://youtu.be/z-YNl_QHHTc | |
| 300b lovers Hi @lynn_olson @atmasphere , Thank you a lot for detailed answers! I have another question: In balanced push-pull self bias output tubes is not a big issue because the cathode resistor and capacitor are out of the main signal path. But what... | |
| 300b lovers I ask again this technical question again. Which rectifier is better: full wave or bridge? My driver stage power transformer has three taps: 250 0 250 and supports both - full wave and bridge. Full wave affords use x2 times bigger DC current. Why... | |
| 300b lovers Japan has a very good used audio stuff market with Tango, Tamura transformer; Kondo, Acrolink cables; used amplifiers and CD player,... Japanese people sell all this stuff on the internal market. A very few used stuff from Japan is sold internatio... | |
| 300b lovers In my case, I compared the sound of my amplifier with different IT resistor load. 120K (Kiwame 2W) vs 56K (Alan Bradley 2W). The sound with 120K resistor was too bright and rough, with 56K tonal balance was more natural and sound was more refined.... | |
| 300b lovers Hi @donsachs and @lynn_olson , Here is square wave 1KHz on my amp output: https://photos.app.goo.gl/jcdjn88Q71WaEvoR9 Output transformer and driver IT have much wider bandwidth compared to input to driver IT. During the measurement the 6sn7 cur... | |
| 300b lovers Hi @donsachs , I changed a load resistor 56K Ohm (Alan Bradley 2W), in my SET amplifier. And still have a 2-3 times bigger overshoot vs Blackbird has. However the sound is more balanced compared to the 120K (Kiwame 2W) load resistor I had befor... | |
| 300b lovers All classic vintage PP amps from 50-60 have very weak PS in terms of chokes, power transformers and especially capacitors values. If you use the same power supply for SET with no feedback with a such PS will be a disaster. But many of these classi... |