I am installing a Graphtech Ghost piezo pickups in my strat with also the Graphtech Hexpander preamp. These will be going out of my guitar via a 13-pin DIN cable like with a Roland GK3 or RMC piezo system.
Power to the preamp system is carried into the guitar via the 13 pin cable. Pin 12 carries -7VDC and pin 13 is -7VDC. I am building a 1 RU breakout box to allow individual (hexaphonic) recording from each string into my DAW.
I am trying to figure out the easiest way to do the PSU for pins 12/13 in this system. I have e-mailed Graphtech to ask what the max voltage the Hexpander preamp can take. I am guessing it might be up to 18V.
I am thinking I should probably ask them how much current the Hexpander draws too, huh? I've read the 13-pin Roland units usually only deliver max 100 mA, so it must be this or less.
I found this simple PSU on ebay which looks like it would suit me well:
New LM317 Voltage Regulator AC DC in 3 40V Out DC1 25V 37V Power Supply Board | eBay
If I go with that, I then need to pick up a power transformer to step down from 110V AC to 3-40 V AC or DC. I was looking at this:
1pc AC Power Transformer Input AC220 110V 60Hz Output AC6 12 24V 120mA 3VA | eBay
That transformer is only capable of 2.88VA. At 18V, this is 160 mA.
I figure this should be enough though, right? Should I be looking at a different 110V AC transformer? Any suggestions if so?
Thanks.
Power to the preamp system is carried into the guitar via the 13 pin cable. Pin 12 carries -7VDC and pin 13 is -7VDC. I am building a 1 RU breakout box to allow individual (hexaphonic) recording from each string into my DAW.
I am trying to figure out the easiest way to do the PSU for pins 12/13 in this system. I have e-mailed Graphtech to ask what the max voltage the Hexpander preamp can take. I am guessing it might be up to 18V.
I am thinking I should probably ask them how much current the Hexpander draws too, huh? I've read the 13-pin Roland units usually only deliver max 100 mA, so it must be this or less.
I found this simple PSU on ebay which looks like it would suit me well:
New LM317 Voltage Regulator AC DC in 3 40V Out DC1 25V 37V Power Supply Board | eBay
If I go with that, I then need to pick up a power transformer to step down from 110V AC to 3-40 V AC or DC. I was looking at this:
1pc AC Power Transformer Input AC220 110V 60Hz Output AC6 12 24V 120mA 3VA | eBay
That transformer is only capable of 2.88VA. At 18V, this is 160 mA.
I figure this should be enough though, right? Should I be looking at a different 110V AC transformer? Any suggestions if so?
Thanks.
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