gres
Full Member level 4
Here’s LM4780 2x60W amplifier with preamplifier on Russian substitute ECC83-6n2p. firstly i made power amp. Then when I was looking for casing and transformer, I found Sharp amplifier – SM5100. I got nice casing from it, with champagne color with aluminum front bar and large toroidal transformer ~150-200W and radiator, potentiometers, slots, step Noble potentiometer for sound loud regulation 2x100kohm and more. After rectify by ultrafast diodes31df6 (25ns) I get 2x38,5V. as a filter – two condensers Nichicon 6800uF/50V each. All electrolytes in amplifier are high quality – Nichicon, Rubicon. All condensers and resistors are metalized. Tolerance of resistors is 1%. Most cables double isolating.
Tube preamplifier consist own transformer, veneer at the core from unitra transformer. I used primary winding and glowing 6,3V. I added anodes winding ( after rectify 150V), half at each corpus, and finally put all to lacquer. Thanks to that it is really silent. Screen is made of zink plate.
Preamplifier has quite strong gain, althought is based on only one triode. Besides it can add a tube sound, clearance and crystal. Preamplifier also has own potentiometer for volume regulation. Preamp can be shut down by switcher.
I put tune indicator – one LM3916 per channel. Works interesting.
Sound from amplifier is clear, with all details. I compare it to very expensive device and must say that it is not worse.
more information at https://www.elektroda.pl/rtvforum/topic1553567.html where you can find original text.
Tube preamplifier consist own transformer, veneer at the core from unitra transformer. I used primary winding and glowing 6,3V. I added anodes winding ( after rectify 150V), half at each corpus, and finally put all to lacquer. Thanks to that it is really silent. Screen is made of zink plate.
Preamplifier has quite strong gain, althought is based on only one triode. Besides it can add a tube sound, clearance and crystal. Preamplifier also has own potentiometer for volume regulation. Preamp can be shut down by switcher.
I put tune indicator – one LM3916 per channel. Works interesting.
Sound from amplifier is clear, with all details. I compare it to very expensive device and must say that it is not worse.
more information at https://www.elektroda.pl/rtvforum/topic1553567.html where you can find original text.
