Hello
In attach the photo of the phono stage with LCR de-enphasis
With two active stage with tube loaded with a 5:1 trafos.
LiberTango ( song from Piazzolla) because is free from Tango transformer that are now almost difficult to find.
The full configuration is:
step-up, first stage with Sowter NI custom trafo 5:1, LCR by Eltra in Turin (Italy) , 600:15Kohm intestage (Eltra), second stage with Sowter Ni.
Then a separate box for power, two indipendent channel, Gz32 as rectifier and the possibility to use C-L (20H) -C filter or ss stabilized that I absolutely prefer
In total are 14 irons
Good results on test and listen.
This after a long run with prototypes done with full Tango irons and EC8020 stuff, same circuit topology, same electrical results ( with little differences)
LiberTango
This was the Tango proto
Walter
In attach the photo of the phono stage with LCR de-enphasis
With two active stage with tube loaded with a 5:1 trafos.
LiberTango ( song from Piazzolla) because is free from Tango transformer that are now almost difficult to find.
The full configuration is:
step-up, first stage with Sowter NI custom trafo 5:1, LCR by Eltra in Turin (Italy) , 600:15Kohm intestage (Eltra), second stage with Sowter Ni.
Then a separate box for power, two indipendent channel, Gz32 as rectifier and the possibility to use C-L (20H) -C filter or ss stabilized that I absolutely prefer
In total are 14 irons
Good results on test and listen.
This after a long run with prototypes done with full Tango irons and EC8020 stuff, same circuit topology, same electrical results ( with little differences)
LiberTango
This was the Tango proto
Walter
The full project was presented in two parts on Audioreview magazine in Italy.
The idea was to set an hardware with the same concept of original circuit with full Tango trafos.
But using other iron and, mainly, othe tubes.
The EC8020, that I know well and consider one of the bet tube ever, is scarce and very expensive.
So one solution, for me is the following schematic
Where the tubes are PC900 that I found at around 1-5 euros each.
I bought around 120 pcs / 100 euros just to understand the quality; are Toshiba .
The selection was not so difficult to get pairs with equals specs.
The gain is good, in this circuit is around 65-68 .
And the Rp and Gm are reasonable .
The iron was Sowter 1160 in NI version, custom order, not cheaper
The SUT is ELTRA Turin, Italy 1:12 and 24 ratio.
The coils are also ELTRA with specs very close to original Tango.
The T2 is ELTRA 600:15 kohm mumetal
The total gain was around 34 dB
The test are fine and the sound good ( opinions of gold ear friends)
Thi is a sofisticated method to put the nucleus in the right position
Thiis is the internal of active part ( without step up due the sonic tests)
+
This is the power
I use a tube rectifier then the ss stabilized , the reason is the rstio s/n that is very good, arund 80 dB
+
Walter
The idea was to set an hardware with the same concept of original circuit with full Tango trafos.
But using other iron and, mainly, othe tubes.
The EC8020, that I know well and consider one of the bet tube ever, is scarce and very expensive.
So one solution, for me is the following schematic
Where the tubes are PC900 that I found at around 1-5 euros each.
I bought around 120 pcs / 100 euros just to understand the quality; are Toshiba .
The selection was not so difficult to get pairs with equals specs.
The gain is good, in this circuit is around 65-68 .
And the Rp and Gm are reasonable .
The iron was Sowter 1160 in NI version, custom order, not cheaper
The SUT is ELTRA Turin, Italy 1:12 and 24 ratio.
The coils are also ELTRA with specs very close to original Tango.
The T2 is ELTRA 600:15 kohm mumetal
The total gain was around 34 dB
The test are fine and the sound good ( opinions of gold ear friends)
Thi is a sofisticated method to put the nucleus in the right position
Thiis is the internal of active part ( without step up due the sonic tests)
This is the power
I use a tube rectifier then the ss stabilized , the reason is the rstio s/n that is very good, arund 80 dB
Walter
Regarding the test lab are good and comparable with the similar full Tango circuit
The sonic results are also very fine
And this using a tube that cost 1 euro each
( I bought 100 pcs )
The PCC900 / 4HA5 now is easy to find between 1 to 5 euros each
nos and nib
And the selection is not so complicated
Walter
The sonic results are also very fine
And this using a tube that cost 1 euro each
( I bought 100 pcs )
The PCC900 / 4HA5 now is easy to find between 1 to 5 euros each
nos and nib
And the selection is not so complicated
Walter
Hi Walter,
the schematic you are sharing here should be the optimum or very near to it. You remember you sent me the PCB some time ago, but I never started. I never started because it was not totally clear to me which design I wanted to build, and I was still missing some parts.
Now everything is here (finally) and I will start in the next weeks.
First step will be the D3a in triode mode with a Monolith 4:1 Nano-X
Then the Hashimoto 600 Ohm LCR equalizer
Then into a LL7902 in 1:4 terminated with 10k, this should represent the 600 Ohm to the LCR circuit (exact value to be tested)
Second step is planned with a D3a or a 8010 (PC900 is interesting, but then I need another two tube sockets)
Then the second Monolith Nano-X in 4:1 or in 2:1, let's see
Power supply will be tube rectified and passive filtered with chokes in a separate case.
The MC stepup transformers are Silvercore 1:10 and on a second input I will be using LL1943 (1:16 or 1:32) for now. Input 3 and 4 will be MM. This should give me all the flexibility for every cartridge on earth. Also I am planning to install a rotary switch on the front with multiple resistors (for loading the cartridge).
The whole project got super expensive and I really struggle: In my next life I would just buy a second-hand phono pre from a famous brand, for the same or less money. I hope there will be a return of invest when it is playing music.
kr,
Bernhard
the schematic you are sharing here should be the optimum or very near to it. You remember you sent me the PCB some time ago, but I never started. I never started because it was not totally clear to me which design I wanted to build, and I was still missing some parts.
Now everything is here (finally) and I will start in the next weeks.
First step will be the D3a in triode mode with a Monolith 4:1 Nano-X
Then the Hashimoto 600 Ohm LCR equalizer
Then into a LL7902 in 1:4 terminated with 10k, this should represent the 600 Ohm to the LCR circuit (exact value to be tested)
Second step is planned with a D3a or a 8010 (PC900 is interesting, but then I need another two tube sockets)
Then the second Monolith Nano-X in 4:1 or in 2:1, let's see
Power supply will be tube rectified and passive filtered with chokes in a separate case.
The MC stepup transformers are Silvercore 1:10 and on a second input I will be using LL1943 (1:16 or 1:32) for now. Input 3 and 4 will be MM. This should give me all the flexibility for every cartridge on earth. Also I am planning to install a rotary switch on the front with multiple resistors (for loading the cartridge).
The whole project got super expensive and I really struggle: In my next life I would just buy a second-hand phono pre from a famous brand, for the same or less money. I hope there will be a return of invest when it is playing music.
kr,
Bernhard