When you say active splitter, I would assume the the 6dJ8 used in the impasse would work? Do you have a suggestion in this regards. It seems funny to put a little tube behind such a brute. I would go with LTP arrangement, but I would really like to preserve the sound. My amp can accept a SE signal and then convert, but I have an affection for balanced for some reason.
As for resistors, I had planeed on trying the AMtrans in this setup. what do you think about low noise/ppm resistors here, at least in grid position? Z foil is used on my brothers RIAA and I will be using the same with mine.
As for resistors, I had planeed on trying the AMtrans in this setup. what do you think about low noise/ppm resistors here, at least in grid position? Z foil is used on my brothers RIAA and I will be using the same with mine.
Buzz. LPT arrangement would need something totally different. not that i regard it but it need some explanation right?
Oops.
LTP = Long Tailed Pair
Could put a 40mA current source in the tail(per Salas).
Unfortunately this would kill the dominant H2 characterstic, although it would proivde other benefits.
LTP = Long Tailed Pair
Could put a 40mA current source in the tail(per Salas).
Unfortunately this would kill the dominant H2 characterstic, although it would proivde other benefits.
Possibly a dumb question, but if I ggo the concertina route, Is it necessary for the element used there to have the same driver current as the 6V6. I am looking at the possibility using a fet. May just have to try both and see.
Ibias is a matter of design choice in a range of valid possibilities, not written in stone. A concertina will not have best balanced output impedance between phases without negative feedback, possibly a trait that lends it a characteristic tone.
Is a concertina different from a unity gain phase splitter like the one in the impasse?
Not really sure what to do and dont want anything that will affect the sonic sig of this pre. Been looking into it all day.
Not really sure what to do and dont want anything that will affect the sonic sig of this pre. Been looking into it all day.
No, its the same concept. Just look in how you bias it when having DC or AC coupling between stages. Anything you add will affect the sig, no doubt. Takes experimentation.
Asked BudP about possible transformer to use. Right now just going to rebuild as posted in your schematic. Gonna play with regs a little, as getting these right seems to add to ability of the preamp. I haev the SSHV2, of course, but may try feeding it with K-multiplier. Also gonna try the HV version of the Jung Super Reg from EUVL posted in that thread. Should be a good comparison for the SSHV2. I also added the final stage of a Millet design i found for use with the CS reg for the filament reg. It basically adds a common mode choke after the LM317 CS. Got 3 sets of tubes, so may try both gain and no gain version. Chose Ohmite WN low PPM, non inductive resistors
Salas,
I have the parts to go dual mono all the way through the prereg. My question is whether or not dual preregs along with dual SSHV2's will create any ground loop issues. I am not doing p2p but instead going with pcb based layout. Here is main board layout and filament reg. I havent completed prereg until I hear from you. I have two Lundahl chokes for prereg adn just deciding whether to combine them in one prereg or seperate them and use for two channels
I have the parts to go dual mono all the way through the prereg. My question is whether or not dual preregs along with dual SSHV2's will create any ground loop issues. I am not doing p2p but instead going with pcb based layout. Here is main board layout and filament reg. I havent completed prereg until I hear from you. I have two Lundahl chokes for prereg adn just deciding whether to combine them in one prereg or seperate them and use for two channels
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If you will go dual go all the way with dual B+ regs, heater regs, and pre-regs to the IEC inlet, don't compromise it by mixing at the pre-reg or at the heaters. Dual has less potential for ground loops anyway.
Just to be clear, we are talking dual everything. Does this inlcude the transformer? I have one, but can get another. The one I have has dual set of windings, but I have heard crosstalk is possible if sharing a transformer between two supplies.
Happening easter everybody, i would improve the supply with a low cost circuit what do you think about these?
Happy Easter. Looks like it will be working good enough as a series reg, although not very sophisticated on the self noise department. Check out Keantoken's HV capacitor multiplier filter too when considering series solutions. Not a regulator, it will follow input level changes slowly. But it will filter rail hum with low output impedance, and will not ask for that choke. Takes two, one for each channel since it can only do up to 30mA safely. Look there under "Other adaptions of the Kmultiplier" The K Multiplier
For heaters the original CCS arrangement turns them on softly in about a minute. For HV a tube rectifier with indirectly heated cathodes will lend a soft start naturally.