I like using those predrilled baseplates. If you leave the legs (standoffs) loose you can mostly always get them to line up to the holes, then tighten to snug. Plus, if you "spacer it a small bit from the bottom panel, you can run wires between them, although I have never done this.
I like the 3 inch high version of chassis for preamps, it allows plenty of height for power supply heat sinks, I used the taller ones as option on the tubecad power supply.
Russellc
C3 coupling cap value
I already started sourcing parts for my ba-3 line stage and my perennial question on this issue has been its large value -10uf-, relative to coupling cap values seen in other preamp. builds. I guess that this value is fullproof for any low input impedance that could be encountered in the next stage. In my case I have a First Watt F4 which has an input impedance of 47k. So, why I could not use a 1uf cap here, wouldn't that be enough, or even 5uf....I ask because in this realm of capacitance values, most of the available caps are for speaker crossovers and there are not too many choices for the best caps without being very costly, for that high capacitance value.
I already started sourcing parts for my ba-3 line stage and my perennial question on this issue has been its large value -10uf-, relative to coupling cap values seen in other preamp. builds. I guess that this value is fullproof for any low input impedance that could be encountered in the next stage. In my case I have a First Watt F4 which has an input impedance of 47k. So, why I could not use a 1uf cap here, wouldn't that be enough, or even 5uf....I ask because in this realm of capacitance values, most of the available caps are for speaker crossovers and there are not too many choices for the best caps without being very costly, for that high capacitance value.
Ok tube cad's PS-19 regulator is out of stock and seems most things on that site are out of stock with no relief in sight.
So plan C for a regulator... ???
For a newbie that also partially builds by looking at pictures, lol, is the salas shunt or super regulator hard to build? (Emphasizing that I'm a newbie). I'm swinging for the fences on this first build. I know there are also kits on eBay, but I am not sure how good those are.
Also on the BA-3 pcb, for C3... what are some options for really nice caps? I'm supposed to avoid film caps? right?
So plan C for a regulator... ???
For a newbie that also partially builds by looking at pictures, lol, is the salas shunt or super regulator hard to build? (Emphasizing that I'm a newbie). I'm swinging for the fences on this first build. I know there are also kits on eBay, but I am not sure how good those are.
Also on the BA-3 pcb, for C3... what are some options for really nice caps? I'm supposed to avoid film caps? right?
Salas shunt and SuperReg are not easy builds. Superreg might be little easier because boards are available from the store but it requires some math to set the voltage. Both are not cheap to make either.
I have used LM317/337 and the SuperReg with the BA-3. Not much difference.
At this point, whether the magic smoke ends up staying inside or not, my build will be anything but cheap, so that is not a factor.
Math in general I can do, but math on something I don't quite have a mental grasp on (electronics) is a bit daunting. I'm more good with, "oh you want 24v... ok use this stuff and it will work."
I would read the SuperReg article and thread and see if you are up for it.
Super Regulator
You will need a separate cap bank and rectifiers in front of the super reg. The Super Reg board has no cap bank and rectifier diodes on board.
or you could spend $15 on Amazon and have it up and running in no time with lm317/337.
Super Regulator
You will need a separate cap bank and rectifiers in front of the super reg. The Super Reg board has no cap bank and rectifier diodes on board.
or you could spend $15 on Amazon and have it up and running in no time with lm317/337.
I did find this online:
Capacitive reactance calculator reactance capacitor frequence - sengpielaudio Sengpiel Berlin
Capacitive reactance calculator reactance capacitor frequence - sengpielaudio Sengpiel Berlin
It uses OPA209 with is +/-18V max.
But the lm317/337 would work and is a good alternative to the PS-19 although a bit more expensive.
Low Current Bipolar Power Supply (LCBPS) - A Regulated CRC Supply
But the lm317/337 would work and is a good alternative to the PS-19 although a bit more expensive.
Low Current Bipolar Power Supply (LCBPS) - A Regulated CRC Supply
Salas shunt hotrodded to the max you can, sounds great. Really affects the sense of openness and space. Thats what I use. Not very difficult to make and plenty of help available.
Finally started using Zen Mod recc of 47uf Elna Silmic2 and Phillips polycarbonate cap for the coupling cap. Let it burn in playing music for at least 50 hours and then listen. I cant make out any sense of space diminishing. Slight change of tone that can be easily changed with P3 adjustment. Great tip. Thanks ZM
nash
Finally started using Zen Mod recc of 47uf Elna Silmic2 and Phillips polycarbonate cap for the coupling cap. Let it burn in playing music for at least 50 hours and then listen. I cant make out any sense of space diminishing. Slight change of tone that can be easily changed with P3 adjustment. Great tip. Thanks ZM
nash
I use this calculator on the same site often:
RC pad corner frequency upper and lower cutoff frequency calculation filter calculate time constant tau RC voltage power calculator capacitance resistance - sengpielaudio Sengpiel Berlin
The whole site is an absolute treasure trove of calculations and background on all things related to audio and sound:
Audio calculations in English acoustics calculator convert audio formulas sound dB audio system microphone electro engineering electronics formula sound recording studio useful stuff free audio calculator recording studio acoustic audio engineering s
Or, for the diy'ers among us who can read German, the root site of it all:
Forum zur Mikrofonaufnahme und Tonstudiotechnik ♪♫♪ Audio Tontechnik Eberhard Sengpiel Community fuer alle Audio-Interessierten - sengpielaudio de = sengspielaudio com und Sengpiel ist Sengspiel ebs Elektro-Akustik Audio Ausbildung
It is absolutely amazing what Eberhard Sengpiel had assembled here ...
Best regards,
Claas
everything above 3x Iq of stage , is pretty much waste of heat
under condition that regulator is carefully designed ,with lowish Rout and phase behavior