tablebeast
Well-known member
OK, so it looks like I am getting my hands on the remains of an RCA BC-6B console. It is a bit of a basket case and there are a lot of missing pieces so I am thinking I will mod and rework this guy to my modern DAW needs rather than trying to restore it. Basically what I have is the console case itself, the controls and wiring from the front panel, and the mic pre chassis with input transformers. I was told even though they aren't attached to the face, all the pots are there. There are no program amps, power amps, or power supply. There are no tubes either.
I don't have the BC-6B Manual but I do have one for the older mono BC-3C. I was told the pres are exactly the same circuits, so I am referencing those. I'd like to get my hands on the real BC-6B Manual if anyone out there has a PDF or can point me to one, I'd be eternally grateful.
So, my main concern first of all is a power supply. Then I have to consider tubes. They all take 12AY7's, two per card. So I need almost two dozen of the suckers. I have 11 preamp cards in all and I was thinking that I would utilize them like this:
8 of the 11 preamp cards I will set up as individual mic pre amps going direct out to my sound card. My sound card has a DSP mixer so all the mixing will actually be done in there and in the computer.
For mixdown I will feed the outputs of my sound card back into a passive mix bus that would feed 2 of the remaining 3 preamp cards. These will feed a two track recorder the final 2-tk mix.
From there I would like to incorporate the monitoring and switching available on the console for additional functionality, but I will get to that after I have figured out all this other stuff first.
The 11th remaining Preamp Card and Transformer I will probably strip for parts and trade for stuff I need on this project. I was told the input transformers are Peerless, though they look like UTC's to me. If anyone is interested PM me.
So, here are the preamps I have:
9 of these Mic Pre circuits:
and 2 of these Line Amp Circuits
Any thoughts on these pres? I can't find a lot of info about them other than what is in this BC-3C manual. It says they have 46dB of gain. It looks like it would be easy to tweak this design for more gain than that (if I need it).
If I were going to mod these pre amp circuits what occurs to me is: First off I'd remove the extra 1.0uF cap and both 220K resistors from the outputs. Then I'd wire the 1.0 cap directly to a 1/4" output jack. Then I'd yank the .0047 cap at C4 and replace it with a .047. I'd like to have DI capability on at least one channel so I was thinking I could strap a 220K resistor from the first grid to ground and install a 1/4" input jack connected through a 10k resistor to the grid. I'd also like to set up a switch to change the load impedance. It has 37 ohm, 150 ohm, and 600 ohm settings on the input transformer. I'd like easy access to all three settings. Lastly I was thinking it would be neat to have adjustable control of the negative feedback to V1A's cathode.
As for the line amp cards (bottom schematic) I would do the same thing as the mic pres only I'd also remove the 3300 ohm resistor on the output.
For a power supply I just bought this thing and it may be perfect, an Oregon Tube Regulated Power Supply:
Let me know what you guys think as I don't know much about Oregon, though their stuff does look badass.
Lastly here are some pics of the console:
Any and all info is appreciated.
I don't have the BC-6B Manual but I do have one for the older mono BC-3C. I was told the pres are exactly the same circuits, so I am referencing those. I'd like to get my hands on the real BC-6B Manual if anyone out there has a PDF or can point me to one, I'd be eternally grateful.
So, my main concern first of all is a power supply. Then I have to consider tubes. They all take 12AY7's, two per card. So I need almost two dozen of the suckers. I have 11 preamp cards in all and I was thinking that I would utilize them like this:
8 of the 11 preamp cards I will set up as individual mic pre amps going direct out to my sound card. My sound card has a DSP mixer so all the mixing will actually be done in there and in the computer.
For mixdown I will feed the outputs of my sound card back into a passive mix bus that would feed 2 of the remaining 3 preamp cards. These will feed a two track recorder the final 2-tk mix.
From there I would like to incorporate the monitoring and switching available on the console for additional functionality, but I will get to that after I have figured out all this other stuff first.
The 11th remaining Preamp Card and Transformer I will probably strip for parts and trade for stuff I need on this project. I was told the input transformers are Peerless, though they look like UTC's to me. If anyone is interested PM me.
So, here are the preamps I have:
9 of these Mic Pre circuits:
and 2 of these Line Amp Circuits
Any thoughts on these pres? I can't find a lot of info about them other than what is in this BC-3C manual. It says they have 46dB of gain. It looks like it would be easy to tweak this design for more gain than that (if I need it).
If I were going to mod these pre amp circuits what occurs to me is: First off I'd remove the extra 1.0uF cap and both 220K resistors from the outputs. Then I'd wire the 1.0 cap directly to a 1/4" output jack. Then I'd yank the .0047 cap at C4 and replace it with a .047. I'd like to have DI capability on at least one channel so I was thinking I could strap a 220K resistor from the first grid to ground and install a 1/4" input jack connected through a 10k resistor to the grid. I'd also like to set up a switch to change the load impedance. It has 37 ohm, 150 ohm, and 600 ohm settings on the input transformer. I'd like easy access to all three settings. Lastly I was thinking it would be neat to have adjustable control of the negative feedback to V1A's cathode.
As for the line amp cards (bottom schematic) I would do the same thing as the mic pres only I'd also remove the 3300 ohm resistor on the output.
For a power supply I just bought this thing and it may be perfect, an Oregon Tube Regulated Power Supply:
Let me know what you guys think as I don't know much about Oregon, though their stuff does look badass.
Lastly here are some pics of the console:
Any and all info is appreciated.
