Nope, not me. I am "Mr.6L6" at audiokarma, but I rarely post there.
If you would like to put a face to the name, here is my 5min presentation from this year's Burning Amp -- https://www.youtube.com/watch?v=V5eOnuQJ3ww
If you would like to put a face to the name, here is my 5min presentation from this year's Burning Amp -- https://www.youtube.com/watch?v=V5eOnuQJ3ww
I've an idea running around in my head. I'd like to build an integrated amp using the ACA combined with the Bottlehead Quickie but with an external power supply. It looks like I'll need 36v and 2.8v DC for the Bottlehead and 19ishv DC for the ACA. Can I do that with this board? I think I'm going to throw in the softstart and DC protection boards as well.
I can handle combining the ACA and Quickie (naming suggestions?) - it's the external power supply that I've never done that worries me.
I can handle combining the ACA and Quickie (naming suggestions?) - it's the external power supply that I've never done that worries me.
***These were my part choices and may be incorrect so be sure to look at each component see if it is correct for your application*****
I ordered parts from Mouser elec. to build my power supply and then saved the basic parts from the BOM to a project that anyone can view and use. Includes most of the basic parts from the BOM minus optional snubber components, bleeder resistors, LED dropping resistors, and filter caps. If any of these components are incorrect please ask this post to be deleted or let me know and I can edit the project to include the correct components. Not sure if this is ok to post but figured it may save someone some time searching for parts for their project. The link to the parts list is here:
http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=126cb116de
I ordered parts from Mouser elec. to build my power supply and then saved the basic parts from the BOM to a project that anyone can view and use. Includes most of the basic parts from the BOM minus optional snubber components, bleeder resistors, LED dropping resistors, and filter caps. If any of these components are incorrect please ask this post to be deleted or let me know and I can edit the project to include the correct components. Not sure if this is ok to post but figured it may save someone some time searching for parts for their project. The link to the parts list is here:
http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=126cb116de
Last edited:
Finished the Quasimodo snubber board tonight, and tested my transformer. Thanks Mark.
Transformer - Antek AN-5218
Cx - 0.01 uF
Cs - 0.15 uF
Rs - 170R
I have the caps, I need to order the resistors.
Anyone help with wattage requirements for the Rs resistors with 18 volt secondaries - 24 volt rail.
Transformer - Antek AN-5218
Cx - 0.01 uF
Cs - 0.15 uF
Rs - 170R
I have the caps, I need to order the resistors.
Anyone help with wattage requirements for the Rs resistors with 18 volt secondaries - 24 volt rail.
Last edited:
Yep, guilty, I stopped reading at "see note 4". I was also pointed to the Quasimodo .pdf on the first page of that thread by Mark, showing 500-600 milliwatt being the needed wattage.
I ordered both some 160 and 180 carbon comp resistors, hoping to find 2 close to 170, and back up with 169 metal film resistors.
Max power per power supply? Driving 5 Leach Amps w 1KVA 84VCT
OK, just wondering what is the max amount of power I can squeeze through one of the power supply circuit boards. I have a 1KVA 84VCT torroidal transformer that I want to use to power 5 Leach Amp modules. From what I gather, it looks like fully populating the cap side of the board w the 10k uF 80V caps I have should cover that side of the issue, and that the diodes would be the limiting factor.
I'd prefer to use the least number of modules possible as I'm attempting to squeeze this all into one chassis smaller than a bus - I have to hit those spousal approval factor specs! I'm running heatsinks with heatpipes that are considerably smaller that the full passive heatsinks spec'd in the Leach amp plans (but that have the same thermal specs of course - they'll just need a small thermal controlled fan that will ramp up when the heatsinks get hot, when they're pumping out enough heat that the fan ramps up, they'll never be heard with that level of sound pressure).
I like the idea of using TO-247/TO-3P or TO-220 package diodes as opposed to using monolithic bridges - why pay for the PCB and not use it, plus much cleaner implementation of snubbers, cleaner ground, etc.
So I guess I'm looking for the largest current capacity diodes that can handle the reverse voltage I need - any suggestions? Years ago, IIRC someone mentioned Schottkey diodes as being quieter than others (or maybe it was a higher slew rate, I don't recall - in any event, they were preferable).
Anyone here with experience with pushing max amounts of power through this board?
OK, just wondering what is the max amount of power I can squeeze through one of the power supply circuit boards. I have a 1KVA 84VCT torroidal transformer that I want to use to power 5 Leach Amp modules. From what I gather, it looks like fully populating the cap side of the board w the 10k uF 80V caps I have should cover that side of the issue, and that the diodes would be the limiting factor.
I'd prefer to use the least number of modules possible as I'm attempting to squeeze this all into one chassis smaller than a bus - I have to hit those spousal approval factor specs! I'm running heatsinks with heatpipes that are considerably smaller that the full passive heatsinks spec'd in the Leach amp plans (but that have the same thermal specs of course - they'll just need a small thermal controlled fan that will ramp up when the heatsinks get hot, when they're pumping out enough heat that the fan ramps up, they'll never be heard with that level of sound pressure).
I like the idea of using TO-247/TO-3P or TO-220 package diodes as opposed to using monolithic bridges - why pay for the PCB and not use it, plus much cleaner implementation of snubbers, cleaner ground, etc.
So I guess I'm looking for the largest current capacity diodes that can handle the reverse voltage I need - any suggestions? Years ago, IIRC someone mentioned Schottkey diodes as being quieter than others (or maybe it was a higher slew rate, I don't recall - in any event, they were preferable).
Anyone here with experience with pushing max amounts of power through this board?
I received the boards (V3.0), they look/feel very solid, quality stuff.
Having only build a few chip-amps before, this is my first stab at a proper PSU so please forgive my ignorance.
I’m putting the BOM together for a F5 build, so I’m looking for a 24Vdc rail of a 2x18v transformer, which I already bought, as well as 8x 10000uf 40vdc caps.
What’s not quite clear to me is how I derive what R1-R8 values to use. The BOM V1.0 10/24/2013 sheet specifies “0.47R - 1R” and there are 3 additional “optional” resistors either side and also what bleeder resistor value would people recommend for a 24Vdc output?
If it’s a question of trail an error, what’s the best way to approach this. Any suggestion would be appreaciated.
Thanks,
Having only build a few chip-amps before, this is my first stab at a proper PSU so please forgive my ignorance.
I’m putting the BOM together for a F5 build, so I’m looking for a 24Vdc rail of a 2x18v transformer, which I already bought, as well as 8x 10000uf 40vdc caps.
What’s not quite clear to me is how I derive what R1-R8 values to use. The BOM V1.0 10/24/2013 sheet specifies “0.47R - 1R” and there are 3 additional “optional” resistors either side and also what bleeder resistor value would people recommend for a 24Vdc output?
If it’s a question of trail an error, what’s the best way to approach this. Any suggestion would be appreaciated.
Thanks,
Last edited:
R1-R8 forms a CRC filer together with the first and final caps. Choosing the resistor values is determined by the current the load will draw from the power supply. You drop the voltage you don't need through these resistors.
It is basically Ohm's Law from there.
Great, thanks for the heads up. Good point to look up what Nelson originally documented, 4x 0R47 in parallel. I’ll start with that, I can always add one or two more later.
As for the bleeder resistor, I’ve found this spreadsheet: [URL="http://www.nilno.com/docs/BleedRes.xls, So"]www.nilno.com/docs/BleedRes.xls, So[/URL] now understand the relationship a little bit better.
As for the bleeder resistor, I’ve found this spreadsheet: [URL="http://www.nilno.com/docs/BleedRes.xls, So"]www.nilno.com/docs/BleedRes.xls, So[/URL] now understand the relationship a little bit better.