It anticipates the plus-five-sigma DIY builder who unwisely uses an 800VA, 2x22VRMS transformer(*), AND an LT4320 based "ideal bridge" rectifier, AND lives in a country where the mains AC voltage varies by as much as plus or minus 15%. Even in this worst case scenario, a 50V capacitor is perfectly safe.
But: this is your DIY project, obviously you can build it however you wish, using whichever parts catch your fancy. Personally, I prefer to have and to recommend a lot of extra safety margin. The 470uF, 50V cap I recommend is Mouser P/N 598-477CKE050M and it costs USD 0.66. Equivalent Series Resistance (ESR) is 0.35 ohms and maximum ripple current is 0.63 amperes. The cheapest 470uF, 25V caps in stock today at Mouser, cost USD 0.25 (140-RGA471M1EBK1012G). They have no ESR specification on their datasheet, and their maximum ripple current is 0.38 amperes.
(*) this transformer is NOT appropriate for an M2x and is a poor choice, in my opinion. Despite that, somebody is going to use one some day, and when their Tucson blows a 25V electrolytic cap, they are not going to be happy.
If you are using the Tucson PCBs from the Store, the length and width don't change when you swap out caps -- only the height. If height is your concern, consult the photographs in post #2 of this thread. You will see that the IPS daughtercard called Norwood has considerably less height than any of the other boards, including Tucson. Especially if you decide to omit Norwood's green output coupling capacitor, replacing it with a shorting wire. With the cap gone you hope the AD744's small DC offset voltage won't make any difference. Either in reliability or in listening pleasure.
Well. I've got 48mm from the sinks to the PSU boards. 10mm standoff to the main pcb. 5mm from main to IPS. 2 board tickness=4mm. så19mm total. That leaves another 29mm untill i hit the PSU caps.
yet a lot more tight on the front half where the transformers will sit. There i'll get 25mm from the sinks to the transformers on the tightest spot.
yet a lot more tight on the front half where the transformers will sit. There i'll get 25mm from the sinks to the transformers on the tightest spot.
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BTW. do you have any IPS8 boards left? Or any other member for that sake? I do have a bunch of AD797's.
Then when you get a pair of Cedarburg and you have ensured they work then just solder the boards to the main amp board using solid copper wire. Then you don't have to think about which bolts and nuts to use 
A next generation M2X could just be with Cedarburg layout on main amp board. Cedarburg is a "luxury" Tucson with good power supply noise suppression and has very low noise and no need to make boards more complicated than that when a single highend opamp is all what is needed to drive the Edcor. Also Cedarburg has no coupling cap.
A next generation M2X could just be with Cedarburg layout on main amp board. Cedarburg is a "luxury" Tucson with good power supply noise suppression and has very low noise and no need to make boards more complicated than that when a single highend opamp is all what is needed to drive the Edcor. Also Cedarburg has no coupling cap.
My question was rather simple:
Will the Cedarburg card with some voltage gain (5-9x) sound worser compared to the Cedarburg buffer with gain=1?
I know in the marauder board for sit Amp you do it wit OPA552 to achieve full voltage swing of 27vpp. As I only need 12Vpp the ad797 with - +15v psu should be ok...
It isn't a problem for me if the F2X in this configuration outputs only 5 to 10w on 8ohm speakers
Will the Cedarburg card with some voltage gain (5-9x) sound worser compared to the Cedarburg buffer with gain=1?
I know in the marauder board for sit Amp you do it wit OPA552 to achieve full voltage swing of 27vpp. As I only need 12Vpp the ad797 with - +15v psu should be ok...
It isn't a problem for me if the F2X in this configuration outputs only 5 to 10w on 8ohm speakers
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to Ryssen
Hello Ake,
you should check your output-offset of the BFB (inputside of decoupling-cap to ground).
If your offset is below 10mV you can delete the decoupling caps (check! -
on your own risk).
Check the pics in my posts #4982 (with decoupling caps - Elco on top, Cc on
underside 1µF);
or without decoupling caps - #4985.
With decoupling caps is always safer... - no DC to the EDCOR!
Cheers
Dirk
Hello Ake,
you should check your output-offset of the BFB (inputside of decoupling-cap to ground).
If your offset is below 10mV you can delete the decoupling caps (check! -
on your own risk).
Check the pics in my posts #4982 (with decoupling caps - Elco on top, Cc on
underside 1µF);
or without decoupling caps - #4985.
With decoupling caps is always safer... - no DC to the EDCOR!
Cheers
Dirk
I am ordering parts for the M2x build but the IRFP240 is out of stock at both Digikey and Mouser without any expected to be in stock for the foreseeable future. I didn't think the IRFP240 and IRFP9240 needed to be matched so I was hoping to order from Mouser to save a few bucks but is my best bet just to order the F5 transistor kit from the DIY Store? Does anybody have any other suggestions?
