|Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum|
Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
||Thread Tools||Search this Thread|
|17th January 2007, 02:51 PM||#1|
Join Date: Mar 2005
I'm playing with my parafeed SE amplifier, now on my bench as a prototype: now it is using a SS CCS on the top of a single KT88, used as output tube (triode strapped).
Actually the CCS is an active current source, like the one developed by Nelson Pass for his amplifiers.
I have an 50 microfarad PP output capacitor, and a toroidal output transformer.
It works, but now I would lower the output impedance (from 2500 to 1500 Ohm), in manner to raise the output power without affecting too much the idle power consumption (now it is running at 600V, 100mA).
Moreover, I would eliminate the SS CCS, cause it dissipates a lot of heat, so I have to use a big heatsink.
My idea was to realise a tube CCS (already ready) with a KT88, and drive with it two KT88 (triode strapped), placed in parallel as output tube.
Would it work? I mean: the upper tube, used as CCS, would drive a 1500 Ohm load, and I'm not sure it can do that.
Another option would be to use two KT88 in parallel also for the CCS, but I don't have them available (I would need 8 of them, two as CCS and to as output tube for each channel).
Or I can use my four KT88 for the CCS (two for each channel), and found a different tube for the output (maybe some real triode).
What do you think?
Thanks in advance,
In Nomine Libertatis Vincula Edificamus,
In Nomine Veritatis Mendacia Efferimus.
|Thread Tools||Search this Thread|
|Thread||Thread Starter||Forum||Replies||Last Post|
|2a3 parafeed||alexg||Tubes / Valves||2||17th November 2007 10:47 AM|
|Power transformer as Parafeed output?||Jeb-D.||Tubes / Valves||57||7th August 2007 01:53 PM|
|to parafeed or not to parafeed that is the question||nhuwar||Tubes / Valves||63||28th February 2007 12:29 PM|
|OTL or parafeed?||Jaime||Tubes / Valves||14||11th December 2005 07:22 AM|
|Parafeed||Brett||Tubes / Valves||14||7th April 2003 12:53 PM|
|New To Site?||Need Help?|