audio-talk

Yep all worked out in theory, gone as far as you can with that TBH, only thing to do now is ack-shirley make it and see what it does in real life. Should be interesting, we reckoned a shade under 1V r.m.s. input for 1.5 Watts out.

I imagine through a low impedance resistor which is also the load for the cartridge. So there would also be a small DC offset yes. That's why I said "in theory"

Or, there could be an isolation transformer here so no DC through the cartridge.

How about, battery bias the grid, then cathode is virtually at 0V so could be DC coupled. :?: Like this, Mike :?: Ah no like DTB's above, common grid but negative battery bias on the grid so's cathode (the input) is at 0V potential. Then don't need no input caps, can be DC coupled. In theory...

The unmarked ones are the 5's Terrif If you had been introduced to slide rules at school all this would make sense :-) Not at my school! :lol: 'Least not unless getting up to O-level math and suchlike, which I wasn't. Nah in my 'circle' mentioning geeky words like 'sliderule' was quite likely to ge...

So imagine the top edge yellow line and the two corner holes moved down by one grid row, then top edge of heatsink is flush on the top edge of board.

Ack-shirley if can trim another tenth of an inch off the top edge makes it £4.67 each

Okey-dokey then, summink like this you mean board size 2.5 x 2.2 inches. Big rectangular thing with 2 holes = vertical finned heatsink with lugs, to be exact any of these Rapid ones (ranges 25 - 50mm high): http://www.rapidonline.com/Electronic-Components/Semiconductor-Hardware/Heatsink/Compact-vert...

Anyone interested in getting some? One ... whatever Will need to make an order with ExpressPCB and I figure not really worth it for less than 30 off, total works out as £158 -ish so means £5.26 per board, not too bad, call it £6.00 plus a jiffy bag and posting. If forum peeps wanted say 10 - dozen w...

Not sure what you mean... A cascode for an active head amp or for the first stage of a phono :?: Yes the latter. The J-FET idea works fine for a high impedance RIAA but is not any good for an LCR, which are usually ultra low Z by valve standards. This is on the output side of the stage? Grounded Gr...

Sounds like an average day here



.

Quite so, it's the unmarked lines that have me confused.


.

So.......is the mini monitor a 4 ohm speaker? Someone once told me that adding series resistance to speakers, doesn't work as expected. But i can't remember the explanation. Might be completely wrong of course. Problee a combination of inductance and resonance; adding resistance increases amp imped...

YES! Got that to work on the calculator.

Just that on the graph are lines between the steps that are marked as 10-5, 10-4 etc., just trying to figure if it means exactly halfway between or not

What about Nick's FET in the cathode path? So is a cascode

Oh-kay (I'm fast losing the plot ) 100uA then.

Or, 20uA if 10^-4.5

My brain 'urts ...