pretty much everything known about concept
so , design specifics left to talk about
I hope 6L6 (and Boyz) will soon arrange Store about Iron Pre , which will certainly Swiss Knife when speaking about modest gain preamps (both SE and Bal) , so Greedy Boyz will have more things to choose from ...... be it from Mithrandir ...... or Dwarfs around
so , design specifics left to talk about
I hope 6L6 (and Boyz) will soon arrange Store about Iron Pre , which will certainly Swiss Knife when speaking about modest gain preamps (both SE and Bal) , so Greedy Boyz will have more things to choose from ...... be it from Mithrandir ...... or Dwarfs around
more musings on subject : What's wrong with the kiss,boy ?
xformer used, by memory , is same as in F6
246/103 - smaller xconductance , lesser cojones to drive xformer
xformer used, by memory , is same as in F6
246/103 - smaller xconductance , lesser cojones to drive xformer
Jensen JT-123-FLPCH costs $37.78 (600/600 1:1)
according to Papa - 50% Nickel core
Specs:
Impedance ratio: 600:600
Turns ratio: 1:1
Maximum 20 Hz input: +20 dBu
THD @ 20 Hz: 0.025 %
Frequency Response: 20 - 20 KHz, -0.04 / +0.04 dB
See spec sheet for additional details
Edcor equivalent would be PC 600/600 and costs $7.23 just like any other one from that line at consumer quantities. Most definitely not close in price but relative to the total cost of building, it's not a deal breaker IMO. The problem seems to be why NP chose the Jensen for the F6 in the first place:
Taken from 6moons F6 Production article:
"Interestingly, the two transformers (M2 and F6) required different core materials to get their sounds. The M2 has an Edcor M6 steel core and the Jensen in the F6 is 50% nickel. The primary difference is that the steel has a high tolerance for saturation, the nickel alloy gives higher permeability and lower distortion at the lower levels required by the F6. It is a case of horses for courses..."
according to Papa - 50% Nickel core
Specs:
Impedance ratio: 600:600
Turns ratio: 1:1
Maximum 20 Hz input: +20 dBu
THD @ 20 Hz: 0.025 %
Frequency Response: 20 - 20 KHz, -0.04 / +0.04 dB
See spec sheet for additional details
Edcor equivalent would be PC 600/600 and costs $7.23 just like any other one from that line at consumer quantities. Most definitely not close in price but relative to the total cost of building, it's not a deal breaker IMO. The problem seems to be why NP chose the Jensen for the F6 in the first place:
Taken from 6moons F6 Production article:
"Interestingly, the two transformers (M2 and F6) required different core materials to get their sounds. The M2 has an Edcor M6 steel core and the Jensen in the F6 is 50% nickel. The primary difference is that the steel has a high tolerance for saturation, the nickel alloy gives higher permeability and lower distortion at the lower levels required by the F6. It is a case of horses for courses..."
Performance aside, the Edcor does not have the separate coils needed.
that , taking F6 in account
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$5 less than Jensen.
In fact, you can get high-nickel (80%) Cinemag CMOQ-4H for less than the Jensen JT-123.
Can we start a dialog on the B1 Xformer preamp? Does it fall under some other existing/similar design, so it's not being discussed?
From BAF 2017.
The switch selects between 6 or 12dB gain. If I want a 3 step switch and the 3. position to be 0dB, then all the transformers windings in series will be parallel with the output...will this be a problem for B1?
3 step switch and the 3. position to be 0dB, then all the transformers windings in series will be parallel with the output
Go out the third switch position to bypass the transformer. Maybe add an extra set of outputs for 0db (buffered out) or not.
PSU have V(-) , GRD and V(+) high probability buffer are similar to this one..
Two first B1 Xformer resistors around the switch are 1M Ohm's.
After the switch log volume potentiometer of 50K maybe..
Schematic source : Passworks
Two first B1 Xformer resistors around the switch are 1M Ohm's.
After the switch log volume potentiometer of 50K maybe..
Schematic source : Passworks
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...same as the DEFiSIT front end ...
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Who have tried building one?
Maximum performance from minimalistic circuit
Trimmer allows use of not very close matched complementary jfets pairs.
What's wrong with the kiss,boy ?
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