Congratulations on your "powerful buffer" design/simulation.
Not sure what your buffer has in common with RJM's Sapphire amplifier, though.
There is no shortage of people like yourself who have posted schematic/simulations of various types of amplifiers on this site, but few seem to have the layout skills needed to make a PCB for all their "new" design.
I'm not saying you're one of those that falls into that category since I don't know you.
When you can layout a PCB and post the Gerber files on this site for this "powerful buffer", then I may consider having a few boards made and trying your design.
Have a wonderful New Year!
Congratulations on your "powerful buffer" design/simulation.
Not sure what your buffer has in common with RJM's Sapphire amplifier, though.
There is no shortage of people like yourself who have posted schematic/simulations of various types of amplifiers on this site, but few seem to have the layout skills needed to make a PCB for all their "new" design.
I'm not saying you're one of those that falls into that category since I don't know you.
When you can layout a PCB and post the Gerber files on this site for this "powerful buffer", then I may consider having a few boards made and trying your design.
Have a wonderful New Year!
The project is completed.There are a few instances .Can be translated into a more suitable branch.sorry for the clumsy translation.
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Sapphire 4.6g
Over the holidays I built a set of the new 4.6g boards, just to check clearances and so forth, as well as have some photos for the webpage and instructions.
R3X (closed loop config) 8-15-25 dB gain settings. Audyn Sn KP 0.47 uF coupling caps.
The completed boards are available, pls. inquire if interested.
Over the holidays I built a set of the new 4.6g boards, just to check clearances and so forth, as well as have some photos for the webpage and instructions.
R3X (closed loop config) 8-15-25 dB gain settings. Audyn Sn KP 0.47 uF coupling caps.
The completed boards are available, pls. inquire if interested.
Attachments
Hi,
I finally got around to stuffing my boards [4.1t] and want to finalize the power supply. I have the DBRB board and diodes, so the rectifier is taken care of. For transformer I have a 2x15V, 100VA [Triad VPT30-3330]. Will that work?
I tried to read through the thread for transformer specs but couldn’t find anything, so apologies if I missed that.
I finally got around to stuffing my boards [4.1t] and want to finalize the power supply. I have the DBRB board and diodes, so the rectifier is taken care of. For transformer I have a 2x15V, 100VA [Triad VPT30-3330]. Will that work?
I tried to read through the thread for transformer specs but couldn’t find anything, so apologies if I missed that.
Thank you. Yes, I know that it is listed, but I’m trying to avoid buying new transformers for this project.
The transformer spec is "two 12 V secondaries". The recommended minimum transformer pwoer spec is "single 50 VA, or two 25 VA if dual mono".
15 V secondaries will bring the V++ up from 17 V to about 22-23 V. The BD135/136 regulator transistors will get a bit warmer, but other than that it will be okay I think as long as you stick with the regular 35 mA bias current build.
/R
Nearly ready to finish this bad boy!! Got some drilling to do and wire up the HP jack (temporary one for now but will fit Neutrik NJ3FP6 eventually)
1500uf and 100uf Panasonic FM
Mundorf Supreme Silver/Gold/Oil
Elma A47 25k series attenuator
Case same as RJM
4.1t Boards fabbed by PCBWay - I thought white would be fun but regret it now - too many different colours happening! should have gone black as per RJM boards or green to match little rectifier boards. At least internal aesthetics will be moot once the lid goes on!!
I have enough BOM for a second set of boards which I'll do with NOS Elna Starget 1000uf (they're a bit big but I think I can make them work) and a Russian PIO for C1 duties.
I'll see you next week with final pics and help on the bias if needed. Looking forward to hearing this compared to my O2 and SSMH. Listening through Sennheiser/Massdrop HD6XX.
Cheers! RJM thanks for supporting this community.
1500uf and 100uf Panasonic FM
Mundorf Supreme Silver/Gold/Oil
Elma A47 25k series attenuator
Case same as RJM
4.1t Boards fabbed by PCBWay - I thought white would be fun but regret it now - too many different colours happening! should have gone black as per RJM boards or green to match little rectifier boards. At least internal aesthetics will be moot once the lid goes on!!
I have enough BOM for a second set of boards which I'll do with NOS Elna Starget 1000uf (they're a bit big but I think I can make them work) and a Russian PIO for C1 duties.
I'll see you next week with final pics and help on the bias if needed. Looking forward to hearing this compared to my O2 and SSMH. Listening through Sennheiser/Massdrop HD6XX.
Cheers! RJM thanks for supporting this community.
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Kewl. I think white+white works.
More importantly one thing I should really address is the way C1 blocks the input screw terminal strip. For the moment I recommend soldering the wires in directly.
Honestly for that case you are using I'd go with a shared power transformer and diodes. Dual mono gets too crowded, I regret going that route on my build. Think about it anyway, if you haven't already drilled the holes.
More importantly one thing I should really address is the way C1 blocks the input screw terminal strip. For the moment I recommend soldering the wires in directly.
Honestly for that case you are using I'd go with a shared power transformer and diodes. Dual mono gets too crowded, I regret going that route on my build. Think about it anyway, if you haven't already drilled the holes.
Yeah - it's tight/fiddly. At the moment I have the input terminals facing towards the variable resistor so I can get at them. However, once I am settled on which open/closed loop options; different C1 caps etc. I plan to remove the terminal strips across the board and directly solder inputs/outputs/rectifier. The Molex connectors will stay only until I'm done playing.
I've looked at yours plenty and I think the C-core trafos are generally smaller than your nice medical grade toroids so I think I will have more free space than you do. (I'd need to buy a more powerful trafo if I dropped dual mono). I stagger the alignment of the trafos and boards rather than align them through the centre, which means there is about 1 inch clearance passed the trafos for the input and the same on the other side where the AC goes up to the front switch. I'm using mini coax for the inputs so that should provide shielding if the physical separation is not great enough.
Hope to have time Sunday to finish up!!
No, really not. That single R-core shown in the photo is more than large enough. I assume it's 50 VA, but even 25 VA would be OK.
/R
I finished mine and loving the sound come out of it. Smooth and transparent I would say. Very neutral and balanced headphone amplifier. I recently have encountered one weird issue. I plugged my dt990 and my AKG Q701 to the Sapphire they sound very weird. The Dt990 lose signal on the right channel and the AKG Q701 sound very narrow. I have tried other headphone like the HD 6XX and Hifiman 400i, they sound right smooth. I am not pretty sure if anyone here have the same issue as mine.