#1
I have a new question posted later in the thread. didnt create new thread because it relates to the power supply. will also post question right in this first post below this bold print.

*new question: hi again. Ive been snooping around the internet and studied some amp theory for like 2 weeks so far and am having some doubts on the power supply circuit for an x88r amp. Ill post the schematic here( http://www.el34world.com/charts/Schematics/files/soldano/soldano_x88r.pdf ). I modded that schematic to accomodate to todays usa 120v outlets since the transformer on this schematic was rated with a 115v on the primaries.



the other scheme used a hammond 269bx had 150v lines and only 1 6.3v filament supply, it rectified the B+ voltage using a bridge rec. the 270cx has 2 6.3v supplies which I really need. Im using just 2 diodes and the center tap to rectify the B+ voltage. is this format ok?

I also wrote a question in the picture pointing at a red box. are so many equal circuits in parallel necessary to supply individual 12ax7 tubes? If my understanding is correct, they should all output the same voltage which should be around 360v. do I really need all that, or can 1 RC segment supply all the tubes(5 12AX7 in the preamp)?

another question is if I really need giant CAN-type filter caps. F&T sells the big caps and they also sell much smaller filter caps(around 1.5-2in long and .8in wide) with the same capacitance and voltage rating. I read somewhere that the smaller caps risk overheating. I really want to save space on the PCB Im making, but I dont like stupid compromises.

Im planning on adding a power amp to this standalone preamp, but I havent really thought of how I will make that section. Ill update this thread over the weekend with an additional section in this psu for the power amp. will adding a power amp affect the preamp section of the psu to the point Id have to change some values and tranny?


old question not relevant anymore: hi, Im building a soldano x88r OD preamp, and so far the only headaches are the chassis and the power transformer. the chassis, Im sure I can find someone to build for me locally. but the PT has been a thorn in my ass. I need one with 300v output and a secondary of 6.3v for tube heaters. the problem with this is the only readily available one I found at a decent price is the hammond 269bx. but the problem Im having with this one is its mounting style. I really want a toroidal style PT so I can make an open top preamp where the PT and components are all inside the box for ease of modding, where in the case of the hammond, Id have to go with the common style of the PT sticking out of the chassis.

I found a refurfished Antec toroidal PT with all my needed specs, but I am highly doubtful of its reliability. Is there any other 300v toroidal PT out there that would fit my needs without destroying my budget. the budget is around $50 + shipping. or is there any way to mount a hammond 269bx inside a chassis?

thanks
Marty Friedman is GOD!

curently in a SEX MACHINEGUNS and X JAPAN phase AND Galneryus AND Anthem phase

damn J-Metal, why you so awesome

My Gear:

Schecter Hellraiser V-1 fr
Ibanez RG321mh
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Last edited by bustapr at Apr 12, 2013,
#3
turret boards was my initial option to buy the chassis, but they only have plain undrilled chassis(other than the jtm/bassman chassis that is of steel and overpriced). I need a big chassis with tube socket mounts inside the chassis. I have no access to tools, so I need to find someone locally to get the job done. and whoever has the tools likely has aluminum and knows how to make an aluminum box and is much easier to deal with than the internet and shipping.
Marty Friedman is GOD!

curently in a SEX MACHINEGUNS and X JAPAN phase AND Galneryus AND Anthem phase

damn J-Metal, why you so awesome

My Gear:

Schecter Hellraiser V-1 fr
Ibanez RG321mh
Fender GDC-200sce
Peavey Vypyr 30 w/ sanpera 1
#5
bump for new question
Marty Friedman is GOD!

curently in a SEX MACHINEGUNS and X JAPAN phase AND Galneryus AND Anthem phase

damn J-Metal, why you so awesome

My Gear:

Schecter Hellraiser V-1 fr
Ibanez RG321mh
Fender GDC-200sce
Peavey Vypyr 30 w/ sanpera 1