EML 300B mesh driven by c3g.
Heaters supplied by a Coleman board.
Interstage coupled (a really well sounding Tribute on amorphe core).
A lot of Tamura irons. Including the famous F-7003 (5K). A little pain for my wallet but a plesure for eys and ears.
Case with frame of walnut wood matching a Corian top.
Dovetails joints on edges.
Professional Neutrik (sepeakon, powercon and rca) connectors which I found more reliable and good quality made for a fraction of the price of "audiophiles" ones.
Gain enough to be driven directly by the DAC (Buffalo I).
Heaters supplied by a Coleman board.
Interstage coupled (a really well sounding Tribute on amorphe core).
A lot of Tamura irons. Including the famous F-7003 (5K). A little pain for my wallet but a plesure for eys and ears.
Case with frame of walnut wood matching a Corian top.
Dovetails joints on edges.
Professional Neutrik (sepeakon, powercon and rca) connectors which I found more reliable and good quality made for a fraction of the price of "audiophiles" ones.
Gain enough to be driven directly by the DAC (Buffalo I).
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Tamura F-7003 & 845
Beautiful amp Popla.
An interesting coincidence, this is my 845 SE 10W amp, 2 stage design using Tamura F-7003. Input tube is C3GS (nude) in pentode mode (plenty of gain), capacitor coupled to 845 tube. Beautiful sound when mated to my Stacked Quad/RTR tweeter, now it power my Tad2001 horn.
Wish we can compare the two amps sound!!!!
Beautiful amp Popla.
An interesting coincidence, this is my 845 SE 10W amp, 2 stage design using Tamura F-7003. Input tube is C3GS (nude) in pentode mode (plenty of gain), capacitor coupled to 845 tube. Beautiful sound when mated to my Stacked Quad/RTR tweeter, now it power my Tad2001 horn.
Wish we can compare the two amps sound!!!!
Attachments
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It should be a shield. Not for mains cables but for signal input cables.
I don't have any metal part in the case and the amp is placed in a bookcase with tons of electronical equipments around. In ls than two meters:
- TV
- Children's PlayStation
- Children's Xbox
- Children's Wii
- Cordless phone
- Router
- Multimedia HT-PC
- DAC
- Blueray reader/writer
not all switched on at the same time but enough to make some noise.
Not cheap, but....I collected components in the last two years founding some bargains.
I went to Tokyo some monts ago and I get the Tamura I had'nt.
I should check but sure no more than 4.000 euros. Including all parts. Don't tell it to my wife.
I have a couple of Tamura B-5003, but the Tribute.....
Speaking around seems a miracle to have been able to receive a couple of Tribute in a relatively short time.
I'll ask him for some more for shure, excellent products, but I know you have to wait.
I don't have a diagram.
But is not a difficult.
- Double choke supply in common mode (half each on the positive side, half on the negative).
- 5u-10mH-70u-10mH-210u-R-70u
- A blue led under the c3g to get -2.8V on the grid
- A power zener 68V under the 300B
- B+ 390 (including the 68 on the grid)->65mA
- B++ 200V
- Interstage
- grid stopper 1k
- grid resistors 100k on both tubes
C3G/300B
Yes, that was C3G driving 845. I took the shield cover off exposing the tube, I call it C3GS nude.
Below is 300B PSE amplifier. Input tube is also C3G painted. Amplifier has tube regulated power supply and oil cap. Originally it was a 3 stage SE 300B with interstage, C3G input driver 300B with interstage driving a SE 300B. It has been changed to 2 stage 15W PSE300B, but it can also be modified to 8W SE 300B without much work. Output transforner is James.
Yes, that was C3G driving 845. I took the shield cover off exposing the tube, I call it C3GS nude.
Below is 300B PSE amplifier. Input tube is also C3G painted. Amplifier has tube regulated power supply and oil cap. Originally it was a 3 stage SE 300B with interstage, C3G input driver 300B with interstage driving a SE 300B. It has been changed to 2 stage 15W PSE300B, but it can also be modified to 8W SE 300B without much work. Output transforner is James.
Attachments
This was the beginning.
Yes I took it from far.
You can se a report of the building process at
www.audiofaidate.org • View topic - Ampli 300b (ancora) - 6) La costruzione
Italian only, sorry.
Yes I took it from far.
You can se a report of the building process at
www.audiofaidate.org • View topic - Ampli 300b (ancora) - 6) La costruzione
Italian only, sorry.
Attachments
This is the Audioromy FU29 pp amp, the main issue with this amp
is "red plating" since cathode is common to both sections,
the only way to balance currents in both plates is thru fixed bias....
(actually there are two other mods that can be done, one is by manipulating
the filament voltage, and the other by tweaking the screen grid voltage
from its set point of about 200 volts....i am looking to implement these
in my upcoming 829b builds)
in order to fix the issue, i changed bias to cathode resistor bias instead...
a 270 ohm 5 watt resistor drops 17 volts, so that at idle, total
plate dissipation for both tubes is about 26 watts, so that either
plate is dissipating about 13 watts...remember that this tube can dissipate 60 watts...
so that longer life expectancy for the 829b is more or less secured.... 8)
before mods..
after mods..
other mods included changing plate caps to ceramic type...
the nylon type used was actually a solderless connector...
is "red plating" since cathode is common to both sections,
the only way to balance currents in both plates is thru fixed bias....
(actually there are two other mods that can be done, one is by manipulating
the filament voltage, and the other by tweaking the screen grid voltage
from its set point of about 200 volts....i am looking to implement these
in my upcoming 829b builds)
in order to fix the issue, i changed bias to cathode resistor bias instead...
a 270 ohm 5 watt resistor drops 17 volts, so that at idle, total
plate dissipation for both tubes is about 26 watts, so that either
plate is dissipating about 13 watts...remember that this tube can dissipate 60 watts...
so that longer life expectancy for the 829b is more or less secured.... 8)
before mods..
after mods..
other mods included changing plate caps to ceramic type...
the nylon type used was actually a solderless connector...
Ooops, sorry, I forgot to answer to your question.
JBL 15" 2226H in BR 90 liters + B&C 2" driver DCM50 with StereoLab horns Tractrix 250 + Fostex T925
Filters round 500Hz and 5.000Hz
Efficency round 96 db/W