You'll get better results from your PSU using 10 * 1000uF caps than 1 * 10000uF cap - its all to do with parasitic inductance and equivalent series resistance - many smaller caps in parallel exhibit better characteristics.
Now something I've tried recently on the merest hint from Mr Pass (long may he post) about capacitance in the PSU - if you want a PSU with muscle, and low capacitance, include some capacitors from the + rail to the - rail. Quite simply they behave as though there is twice the capacitance in the supply (due to the way capacitances sum) - and it sounds good too!
Owen
Edit - The LF353 lost very little in terms of naturalness to the DHT, but has 'muscle' and control - I've a selection of 'boutique' opamps too, that have many fine charecteristics, but oddly I kept gravitating back to the LF353. As it is a dual opamp, use a single chip per channel, and bypass in the same way as the LM38NN chip - this I believe is vital in getting the best from this opamp.
Owen
Now something I've tried recently on the merest hint from Mr Pass (long may he post) about capacitance in the PSU - if you want a PSU with muscle, and low capacitance, include some capacitors from the + rail to the - rail. Quite simply they behave as though there is twice the capacitance in the supply (due to the way capacitances sum) - and it sounds good too!
Owen
Edit - The LF353 lost very little in terms of naturalness to the DHT, but has 'muscle' and control - I've a selection of 'boutique' opamps too, that have many fine charecteristics, but oddly I kept gravitating back to the LF353. As it is a dual opamp, use a single chip per channel, and bypass in the same way as the LM38NN chip - this I believe is vital in getting the best from this opamp.
Owen
http://www.diyaudio.com/forums/attachment.php?s=&postid=756655&stamp=1130843566
this is how i make huge capacitance.i dont use single big caps but multiple small ones.this pic is of capacitance i have used in car(power supply energy storage caps).four of these in total,all in parallel.2200uf/25 volt each.for home use also i use this method.
isn't it a good psu????or more (not wastage of money) can be done.
this is how i make huge capacitance.i dont use single big caps but multiple small ones.this pic is of capacitance i have used in car(power supply energy storage caps).four of these in total,all in parallel.2200uf/25 volt each.for home use also i use this method.
isn't it a good psu????or more (not wastage of money) can be done.
Thats right..but I am will try with a 10000uF/63V...i have find a find
..i think. Capacitors named: Evox-Rifa PEH169.Max ripplecurrent at 100 Hz: around 12-14 A
ESR 20C and 100 Hz: Below 10 mOhm
Pretty big
DxL : 65 mm x 130 mmhttp://www.svalander.se/shoppen/lytar.htmhttp://www.svalander.se/shoppen/lytar.htm
http://gaincloning.mysite.wanadoo-members.co.uk/
It's a simple unity gain system. Sounds damn fine.
Owen
It's a simple unity gain system. Sounds damn fine.
Owen
carlosfm said:
2 laCie electronBlue 19s running at 1600x1200.
Is there a larger image then this one?
An externally hosted image should be here but it was not working when we last tested it.
If there is then the site isn't giving me any links to it.
Even blown up in Photoshop there is at least 1 value that i have to guess at and the others are far from distinct.
dave
Ok, so the image is small (original 'wanadoo' hosting restriction) - it took some work to get it that readable...
Now
Buffer:
Ri = 47K
Rf = 47K
Rpot = circa 40k, not greatly critical.
Chip LF353
Supply rails +/- 12V
Output capacitor 2.2uF stacked polypropelene (Wima cant remeber the exact specifications - and sadly cant look at them - the amps now reside in Jersey..)
The main 'chipamp' stage is from Decibel Dungeon.
Ri = 10K
Rf = 2, 423K resistors in parallel
56K resistor from input to ground.
I used the 100R resistor and .22uf cap to 'float' signal ground from safety ground.
I hope this clears this all up, and sorry if you've had difficulties reading it.
Owen
Ps. This isn't the end of my gaincloning... far from it. Infact, I am waiting to purchase a DCX2496 (when they're available again), to be driven by my transport and DAC, a music server and a restored Garrard 401 with mission 774LC arm). In the hold, I have all the parts needed for the 4 gainclones that will be driving the B+W's actively(hence needing the DCX2496), and am designing the preamp as we speak (Pic controlled, relay ladder attenuator, IR control for the 4 output channels from the DCX2496), and I've got to build a plinth/ strip and rebuild my 401... too many things and no time
Have fun
Owen
Now
Buffer:
Ri = 47K
Rf = 47K
Rpot = circa 40k, not greatly critical.
Chip LF353
Supply rails +/- 12V
Output capacitor 2.2uF stacked polypropelene (Wima cant remeber the exact specifications - and sadly cant look at them - the amps now reside in Jersey..)
The main 'chipamp' stage is from Decibel Dungeon.
Ri = 10K
Rf = 2, 423K resistors in parallel
56K resistor from input to ground.
I used the 100R resistor and .22uf cap to 'float' signal ground from safety ground.
I hope this clears this all up, and sorry if you've had difficulties reading it.
Owen
Ps. This isn't the end of my gaincloning... far from it. Infact, I am waiting to purchase a DCX2496 (when they're available again), to be driven by my transport and DAC, a music server and a restored Garrard 401 with mission 774LC arm). In the hold, I have all the parts needed for the 4 gainclones that will be driving the B+W's actively(hence needing the DCX2496), and am designing the preamp as we speak (Pic controlled, relay ladder attenuator, IR control for the 4 output channels from the DCX2496), and I've got to build a plinth/ strip and rebuild my 401... too many things and no time
Have fun
Owen
tmblack said:
If you like that...
tmblack said:
Well then let me tell you that there's much more than the chip to make the (chip)amp.
For instance, your beloved OPA549 sounds fast, extended, detailed, very good at low gains (under 10x).
Certainly not warm. It sounds warm at 'normal' gains (above 10x), because of it's limited bandwidth.
The lower the gain the better (IMO) it sounds.
So, you just gave your (correct) oppinion about your amp, not the OPA549.
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