[stevenkelby]

Quote:

Originally Posted by i has a can /img/forum/go_quote.gif Why do you have a 1/4 locking jack in there?

Yeah I may one day want to use a 1/4" jack to connect it to something (not cans obviously!). I may never use it, then again I may. No harm having it there so why not.

I may make a 1/4" to RCA cable to connect to a stereo somewhere. Better than 1/8" I guess and should be the same as RCA as the ground is combined anyway.

 

[germanium]

Stevekelby wrote;

"I used OIMP V-caps, 250VDC 3.3uF. I wanted to have charging ability, RCA, mini and 1/4" outputs."

Those caps are too small in capacitance to drive anything but anouther amp. Headphones would have very very severe bass rolloff if used with these caps In fact you wouldn't get anything but upper mids & treble if headphone were plugged in directly to the 1/4" jack. I hope it was your intention to drive a very high impedance headphone amp. Something on the order of at least 10,000 ohm input impedance.

OOPs I see that is your intention to drive an amp which is good. Probably best to drive an amp with mosfet or tube front end as these draw no current in & of themselves. Thier capacitance is far lower than your capacitace so they would not limit frequency response in & of themselves so unless you used too low impedance between your caps & amp you will be fine. Bipolar transistors draw some current & I would not recommend them at the front end of the amp circuit when driving with such a low capacitance.

 

[sinsiang]

Sorry for the late reply, I misread the pics so it is way 2 is correct for this function. Sorry for the inconvenience.

siang

 

[stevenkelby]

Quote:

Originally Posted by germanium /img/forum/go_quote.gif Stevekelby wrote; "I used OIMP V-caps, 250VDC 3.3uF. I wanted to have charging ability, RCA, mini and 1/4" outputs." Those caps are too small in capacitance to drive anything but anouther amp. Headphones would have very very severe bass rolloff if used with these caps In fact you wouldn't get anything but upper mids & treble if headphone were plugged in directly to the 1/4" jack. I hope it was your intention to drive a very high impedance headphone amp. Something on the order of at least 10,000 ohm input impedance. OOPs I see that is your intention to drive an amp which is good. Probably best to drive an amp with mosfet or tube front end as these draw no current in & of themselves. Thier capacitance is far lower than your capacitace so they would not limit frequency response in & of themselves so unless you used too low impedance between your caps & amp you will be fine. Bipolar transistors draw some current & I would not recommend them at the front end of the amp circuit when driving with such a low capacitance.

Thanks for the info. I do plan on mosfet amps only, 20'000 ohm minimum.

 

[germanium]

Quote:

Originally Posted by stevenkelby /img/forum/go_quote.gif Thanks for the info. I do plan on mosfet amps only, 20'000 ohm minimum.

Good man. Looks like you have at least put a little thought into this.

 

[m1ck3y]

hi, what is a v-cap?

 

[amb]

BP stands for "bi-polar" (aka non-polar electrolytic). They used two different capacitor symbols to denote electrolytic (with the dash marks) and non-electrolytic types. This is common practice in Japanese schematic diagrams.

The amp has two sets of inputs, one is AC-coupled (the signal goes through those coupling capacitors) and the other is direct-coupled. The former is for use with sources that may have DC offset.

 

[rxc]

Quote:

Originally Posted by m1ck3y /img/forum/go_quote.gif hi, what is a v-cap?

http://v-cap.com/oilcapacitors.html

 

[thebob]

Quote:

Originally Posted by amb /img/forum/go_quote.gif BP stands for "bi-polar" (aka non-polar electrolytic). They used two different capacitor symbols to denote electrolytic (with the dash marks) and non-electrolytic types. This is common practice in Japanese schematic diagrams. The amp has two sets of inputs, one is AC-coupled (the signal goes through those coupling capacitors) and the other is direct-coupled. The former is for use with sources that may have DC offset.

The Japanese text above the BP 100uF says 'DC cut condenser'. It is JIS (Japan Industrial Standard) to put the little slanty lines between the plates of a BiPolar cap.

Hope this helps.

 

[illkemist]

Nice work on the dock. It got a lot of attention at the Tampa meet this past weekend. I'm sure that at least one person is going to contact you. Maybe more.

 

[Baird GoW]

Hi could you please make a bill of materials for that DIY mod? It looks good and easy.