Three terminal reg, shunt reference volt reg and then an emitter or source follower (C-multiplier).
For John Curl, lowest possible noise is a priority of his. Three term regs are not quiet enough. And, also does this for each amp stage for best isolation.
THx-RNMarsh
For John Curl, lowest possible noise is a priority of his. Three term regs are not quiet enough. And, also does this for each amp stage for best isolation.
THx-RNMarsh
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Hello Richard,
I ordered a kit of your amp, and now just looking for some PSU. I planning to use that amp with Audeze LCD-3 phones, so I think to go for 15-17 V rails.
Now there is a lot of PSU kits on ebay, so I'm interesting to hear you suggestion about the PSU kits below:
Kubota
Dual Rail TPS7A4700
LT1083
Are these any good to use with quality head amp ?
I ordered a kit of your amp, and now just looking for some PSU. I planning to use that amp with Audeze LCD-3 phones, so I think to go for 15-17 V rails.
Now there is a lot of PSU kits on ebay, so I'm interesting to hear you suggestion about the PSU kits below:
Kubota
Dual Rail TPS7A4700
LT1083
Are these any good to use with quality head amp ?
I looked at them and think the order you have them is the order I would try. However, I am tempted to use the dual rail because it has a more comprehensive spec and higher output voltage, if you want to experiment with other devices and voltages. They all seem OK to me.
I am curious about shunt or push-pull/active ground ref type but dont know of any kits.
-RNM
I am curious about shunt or push-pull/active ground ref type but dont know of any kits.
-RNM
Here is what I used ... a heckuva lot cheaper and works great! I have even cranked it up to +/-18V and the Marsh gets better the higher you crank it!
1 25 37V Adjustable Voltage Regulator Module Based on LM317 LM337 | eBay
Just an info,
on my board power supply for output pair and the front end is initially separated, easily joinable with the solder blobs at the bottom,
but if you are crazy enough 😀 you can use separate power supplies.
on my board power supply for output pair and the front end is initially separated, easily joinable with the solder blobs at the bottom,
but if you are crazy enough 😀 you can use separate power supplies.
Ebay mucho bang for the buck power supplies:
New Assembled LM317 LM337 Dual Power Adjustable Regulated Power Supply Board | eBay
Class A Parallel Type Regulated Power Supply Finished Board | eBay
New Assembled LM317 LM337 Dual Power Adjustable Regulated Power Supply Board | eBay
Class A Parallel Type Regulated Power Supply Finished Board | eBay
I tried the second one you linked above and it did not work with the Marsh. I do not think it could supply enough current.
The CCS is set to 1.25V/10R = 125mA in stock form. Marsh HA requires 200mA. Solder another 10R on top of the set resistor will raise the CCS to 250mA and will be able to power the Marsh. Or, use 2, one for each channel. Why not for this price 🙂
This reg does require a dual secondary transformer. A CT transformer will not work.
Though the amps need 100mA idle for each channel.... dont forget to add enough for the headphone draw also.
-RNM
-RNM
Good point, I actually have a couple of these regs somewhere. Sounds like a 5R in parallel to the 10R is the way to go. That should give a 375mA CCS.
Still waiting for the 2N5460 to come, slow boat from China, it has been 4 weeks now. Maybe missing in transit, the tracking status hasn't shown it arrived US turf at all, sigh.
Still waiting for the 2N5460 to come, slow boat from China, it has been 4 weeks now. Maybe missing in transit, the tracking status hasn't shown it arrived US turf at all, sigh.
I did notice this parts at Mouser and are in my shopping cart. That indeed will be my last resort.
Why? The 2N5457's that I have are Fairchild, so I am kind of trying to avoid mixing jfet manufacturers. Not sure I am worrying something that I shouldn't.....
Thanks to Jack's new board which allows me to use the sot-23 parts. I am likely to go that route if no TO-92 2N5460 in sight by end of next week. Just a little more challenging for the 57 yr old to do the matching, but then this is part of the fun 🙂
Why? The 2N5457's that I have are Fairchild, so I am kind of trying to avoid mixing jfet manufacturers. Not sure I am worrying something that I shouldn't.....
Thanks to Jack's new board which allows me to use the sot-23 parts. I am likely to go that route if no TO-92 2N5460 in sight by end of next week. Just a little more challenging for the 57 yr old to do the matching, but then this is part of the fun 🙂
A SOT-23 test socket will cost you about 24USD.
So if you have 50 FETs to match, it would have already paid for itself.
Good investment, I can assure you.
Patrick
So if you have 50 FETs to match, it would have already paid for itself.
Good investment, I can assure you.
Patrick
I have made such a 'socket' out of a scrap piece of circuit board. Just use a knive to carve a Y into the copper and then solder some strips to each of the three planes. I then used a toothpick to securely press each DUT onto the copper pads while performing the measurement.
I used dual PS's on the board and for me, it has always improved sound on anything I have made. I have a preamp with two PS's that could power a small speaker amplifier (each one) but the unlimited (almost) reserve and clean DC gets you where you need to be for that part of the equation. When I can do a dual supply I use what I call the pseudo dual PS, that used a RCL or RCRC to divide the supply and you can't really hear the difference from a true dual supply unless there isn't enough upstream to begin with.
Anybody tried Placid HD BP from twisted pear audio ?? Looks very impressive. Can to output more than 500mA with increased heatsinks.
