I wanted a nice powerful stereo amplifier for studio use, I'm pretty sure this will drive a few pairs of headphones/speakers though I've only tried it with one pair.
this would also be well suited for a nice set of powered monitors for a laptop or any other application.
anyway, I found the TPA1517 from Texas Instruments and it works great.
the powersupply needs to be very clean maybe even external to the unit itself. you'll notice there is a resistor across the terminals of the big capacitor (4700uf) this is a bleed resistor and its purpose is to discharge the capacitor once it is powered off, with the value stated it takes about 3- 4 minutes to discharge the 4700u 40v capacitor. it's not a necessity but it's advised to avoid electric shocks - even the 40 volt cap I used packs a nasty punch.
when you turn it on don't have your headphones over your ears - this is very very loud so the input signal needs to be raised very gradually
Now with this as it is, Is it a simple case of building in a two or four way buffered splitters (just for example) for the desired number of channels? Or am I as usual thinking way to simple when in fact it is alot more involved than I would think Paul? At last not having the shell out on a quality headphone distro amp that will actually properly drive pretty much every closed and open backed headphone model I am familar with (for reference here Beyerdyanamic's DT100 closed back models, Pretty much the default pair dished out at any studio for tracking as they are REALLY closed/Nothing gets out of them suckers spill wise! Along with the sublime AKG K702 model which are open backed designed and easily the most dependable refference set I have had the pleasure of using. They are as good as it gets for achieving reliable results if used now and again for mixing on *when monitors are not an option* I can not say that about almost any other pair of headphones I am aware of). Cheers dude in advance
ReplyDeleteI probably jumped the gun power wise with this, it's way too powerful for headphones unless you seriously attenuate the output so you don't blow your head off however with modifications this is a great IC to go at the heart of something
ReplyDeleteI'm comparing the schematic to the layout and was confused by something. Should the jumper wire on the layout that presently goes from B27 to L27 go instead from B27 to N27 ??? Also, it looks like the schematic has a 2.7k resistor that you must have changed in the vero layout to 12k 7 watt....pretty obvious....it's really the jumper wire being the reason for the comment. I wasn't seeing how the flow through L1 was comparing with the schematic. Maybe I'm just not comparing schematic to vero layout properly.
ReplyDeleteaye I think you're comparing it wrong. it is built and definitely works so try not to worry.
ReplyDeletethat resistor is just a bleeder resistor that discharges the capacitor, that value only effects the speed that it discharges - I used the 12K one on one of them and a 2.7k on another to make it discharge faster
Is there any way to add a volume pot to this setup to avoid the loud start up? Maybe even a volume power switch in one.
ReplyDelete