Lowfreq
Well-known member
Ok, I've deiced to try try a ELAM 250 circuit with my Tim Cambell CT12.
I have a G7 in a Nady 1150 body with it at the moment, but I'm not 100% happy with that circuit. (the capsule really shines in omni however)
Besides I want to try something p2p, and try something that was orginally used with the CK12.
I'm gonna try it with a cinemag2480, and a jensen D.I transformer to see if I prefer either one. (I know Gus is not a fan of the 2480)
I'm using a 6072 for the tube too.
Now I've read countless threads on the 250/251 and found the answers for a lot of my questions, so hopefully I'm not asking the same things.
1st off, the 100pf and the 4800pf in the schematic have a voltage rating of 500v and 350v. For a circuit that's kinda around 120v, do they need to be that high?? Coz I can get hold of some Polystyrene caps at 160v(the G7 BOM doesn't need any caps over 160v)
Silver Mica's all seem to be in the 300-500v mark so I could use those, but would Polystyrene be better? What have previous builders used here? Other types of film caps? Are the micas good enough?
2ndly how close to the original cap values do I need to be, coz I can find 4700pf or 5000pf caps all over the place, but 4800pf?
I could just parallel another 100pf..................
And the 20uf. I have found some, but most are motor caps and I don't need 600v rating.......just 6v
Again I could just parallel 2 x 10uf caps, but is a 22uf cap close enough??
3rdly, my G7 PSU is setup for 120v for the ck12 capsule. can I just use that and not use the pattern selector??
Or is there a better option? A better psu?? Should I bother building the one in the schematic.
And for those of you who used a relay for the pattern selection, would you be so kind as to show me how you set yours up? I'm trying to decide if I want to drill into the mic body for switching or just use a relay
And also, have many people noticed a bit of body resonance in their apex 460/nady 1150? Just walking around the room caused mine to "boing" in the low mids a lot.
I dropped the 2.2uf output cap to 1uf in my G7 and that helped to tame it down. but can I put anything inside the mic to control the vibrations? (leaving enough room for the circuit and the heat of it)
I think that's it. Sorry if these have been answered before.............. I did read a lot of threads and internet searches on this.....
I have a G7 in a Nady 1150 body with it at the moment, but I'm not 100% happy with that circuit. (the capsule really shines in omni however)
Besides I want to try something p2p, and try something that was orginally used with the CK12.
I'm gonna try it with a cinemag2480, and a jensen D.I transformer to see if I prefer either one. (I know Gus is not a fan of the 2480)
I'm using a 6072 for the tube too.
Now I've read countless threads on the 250/251 and found the answers for a lot of my questions, so hopefully I'm not asking the same things.
1st off, the 100pf and the 4800pf in the schematic have a voltage rating of 500v and 350v. For a circuit that's kinda around 120v, do they need to be that high?? Coz I can get hold of some Polystyrene caps at 160v(the G7 BOM doesn't need any caps over 160v)
Silver Mica's all seem to be in the 300-500v mark so I could use those, but would Polystyrene be better? What have previous builders used here? Other types of film caps? Are the micas good enough?
2ndly how close to the original cap values do I need to be, coz I can find 4700pf or 5000pf caps all over the place, but 4800pf?
I could just parallel another 100pf..................
And the 20uf. I have found some, but most are motor caps and I don't need 600v rating.......just 6v
Again I could just parallel 2 x 10uf caps, but is a 22uf cap close enough??
3rdly, my G7 PSU is setup for 120v for the ck12 capsule. can I just use that and not use the pattern selector??
Or is there a better option? A better psu?? Should I bother building the one in the schematic.
And for those of you who used a relay for the pattern selection, would you be so kind as to show me how you set yours up? I'm trying to decide if I want to drill into the mic body for switching or just use a relay
And also, have many people noticed a bit of body resonance in their apex 460/nady 1150? Just walking around the room caused mine to "boing" in the low mids a lot.
I dropped the 2.2uf output cap to 1uf in my G7 and that helped to tame it down. but can I put anything inside the mic to control the vibrations? (leaving enough room for the circuit and the heat of it)
I think that's it. Sorry if these have been answered before.............. I did read a lot of threads and internet searches on this.....