The future?
This is my new 24bit 192khz source. So far the sound is excellent… all it needs is a little tube love 
It may be too tight inside for an all in one source / tube amp, but there is plenty of room to make it into an optocoupler volume control LC 26 tube preamp.
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Heya Eric,
Haven’t heard from you for a bit, still trying to figure out the GG Pre and LDR volume, any chance of a bit more info please? Been playing with a 16xTDA1543 DAC here, sounding really quite nice, would like to be looking at something for the HI-res stuff, will have a geezer at the DAC Mini,
Keep in touch, hope all is well!
Drew.
June 18, 2011 at 9:19 pm
Hi Drew,
Where are you stuck with the GG preamp? You can tap off the 12V heater regulator to the EZ1588CT for the 2.5V source. The +2.5V then goes to the stereo 100K pot which splits voltage between the series and shunt optocoupler LEDs. The series optocouplers replace the 1K grid stopper resistors right on the circuit board. The shunt optocouplers then go from the grid to signal ground. Clear as mud?
June 18, 2011 at 9:30 pm
Hi Erick: Still really enjoying my (Greenvalve modded) GG pre!
Expand a bit on the above dac, what brand/how much &c.
I’ve not put my foot in those waters, but am starting to gather info
Best, Don
June 18, 2011 at 10:20 pm
Yup, mud, confused more like it, I have a photo of yours where you have the optocouplers at the sides of V3, but in the pics of the schematic I sent I cannot see a 1K resistor there? Are you running volume control after V1 and 2 or before? In the photo’s of Don’s they are all over the boards!
Just a touch confused!
Thanks!
June 19, 2011 at 8:05 am
Oh Don,
I still remember when you first turned me onto 24bit files… my boy was just born, it must be almost three years ago now! Well, 24bit is nearly as good as vinyl (my vinyl rig is top notch) but 24bit is so convenient. Just in the last few hours I have listened to tracks that were recorded from vinyl to 24bit from a dozen different albums. It is nice just to click and listen! CEntrance seems to be a great value, and it sounds like they know what counts for high res digital music reproduction.
CEntrance Products
Plus it makes a guy feel like a kid again… do you remember recording your favorite music from the radio? Its really a lot of fun, more fun listening to tons of music than I have in a long while.
June 18, 2011 at 10:34 pm
Love the picture, could we use it on our blog? With proper attribution of course…
Cheers — Michael — CEntrance
June 21, 2011 at 11:09 pm
Michael,
That would be very nice, thank you !
Lovin’ the DacMini !
June 22, 2011 at 5:24 am
Hey Buzz,
Thanks for coming back to me, is your yahoo email still running?
You mean the 10k from V3 to V1B at the output stage going to the grid of V1 from the plate of V3? if so, this to me then would be sending the signal full “volume” through V1 and V2, then by varying the grid at V1B it changes the output volume? So from about 40 ohms to 25K through the LDR’s?
Can send a drawing of what I mean, don’t want to take up all the room here, you also had the other resistor next to the 10K bridged out or removed, reasoning?
Thanks,
Drew.
June 28, 2011 at 8:37 am
just to be able to get a notification, to quick on the enter key I was!
June 28, 2011 at 8:38 am