Take the chassis to IEC mains grounding wire away from the toroidal's screw. Use a dedicated chassis mounting point for it. 50VA toroid will be fine for your setting while 80VA will be rich enough if you feel like overspecifying it.
How you can measure output offset if the output relay makes no contact for instance? Impossible. Maybe you used latching type relays? Correct type is Ea2-12NJ
How you can measure output offset if the output relay makes no contact for instance? Impossible. Maybe you used latching type relays? Correct type is Ea2-12NJ
Also make continuity tests in case you switch in some other input from the one you expect by some mistake in the control switch's wiring. Or it does not allow to engage at all for some reason.
Thanks, Salas.
I have NEC EA2-12NU. It is non latch tipe, but leg 1 is + , like in the picture.
+
1 2 3 4 5
10 9 8 7 6
Is it true, that on the bord for this configuration of pins, leg 10 is + .
matjaž
I have NEC EA2-12NU. It is non latch tipe, but leg 1 is + , like in the picture.
+
1 2 3 4 5
10 9 8 7 6
Is it true, that on the bord for this configuration of pins, leg 10 is + .
matjaž
Did you jumper the "note" pads by the way? Can you find about +12V on pin 1 of the input relays? Are the diodes next to them correctly orientated?
Salas thank you for your coatching. I just found the mistake. I did not solder one pin in the input relay. Output relay is working properly so that the offset is just that i wrote. Must i make some rekonfiguration of jfets.
At first sight DCB1 is a hugh difference versus my old preamplifier. Tomorrow I will better describe my opinion.
Salas, thank you.
At first sight DCB1 is a hugh difference versus my old preamplifier. Tomorrow I will better describe my opinion.
Salas, thank you.
Opinion, which I promised. My system now consists of:
Mac mini with iPad Remote
Arcam RDac
DCB1 before Valve Preamplifier
MiniDSP
One chanel 2x monoblocs Pass F5 (total 4 x monoblocs F5 and 2x monoblocs Zen V4)
OB, U and H frame (15 kombination)
Gaina is just enough (i have 20k potentiometer, which is completley open, I think to cahange it for resistors but I need DCB1 also for phono)
The sound has a better resolution, a better stage and better bass. I think I've come up with DCB1 to the end of my DIY boundaries.
Matjaž
Mac mini with iPad Remote
Arcam RDac
DCB1 before Valve Preamplifier
MiniDSP
One chanel 2x monoblocs Pass F5 (total 4 x monoblocs F5 and 2x monoblocs Zen V4)
OB, U and H frame (15 kombination)
Gaina is just enough (i have 20k potentiometer, which is completley open, I think to cahange it for resistors but I need DCB1 also for phono)
The sound has a better resolution, a better stage and better bass. I think I've come up with DCB1 to the end of my DIY boundaries.
Matjaž
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I plan on building the B1 and the Aleph J and possibly eventually the F5 I found what looks to be legitimate matched 2SK170 GR's from ebay.
http://www.ebay.com.au/usr/lady.twilight
I might buy some and do testing seems pretty cheap too
by the way better to copy the link and paste it into your browser
http://www.ebay.com.au/usr/lady.twilight
I might buy some and do testing seems pretty cheap too
by the way better to copy the link and paste it into your browser
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There is a problem with ebay links. The goalposts keep moving,
http://www.diyaudio.com/forums/forum-problems/240776-ebay-links-not-working-properly.html
just out of interest how well does the mez B1 fair as a pre for the F5? It seems as if the F5 needs a lot of gain is the mez B1 sufficient for it?
Depends on your source and speakers. The B1/DCB1 "only" provides unity gain, in other words, no voltage amplification.
There are enough guys saying they are OK with their B1+F5 system gain given their listening habits, room, and speakers sensitivity. And they enjoy the combo as very synergistic for tone etc. I still believe they need +10 to 15dB to hear the dynamics even better.
If source and/or speakers are above the norm for output then its a different ballgame indeed.
A quick search suggests that the F5 needs about 4V input for full output, so given that most sources nominally have 2V line level output, a B1+F5 combo may work in some cases.
Edit: With a voltage gain of 15.3dB=20*log(x) and a maximum output voltage of +/-20V (from manual), the amplification factor x=10^(15.3/20)=5.82 and therefore the input voltage required to drive it to full output should be 20V/5.82=3.42V.
Edit: With a voltage gain of 15.3dB=20*log(x) and a maximum output voltage of +/-20V (from manual), the amplification factor x=10^(15.3/20)=5.82 and therefore the input voltage required to drive it to full output should be 20V/5.82=3.42V.
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