its just a bread board, connect the caps in series, -+-+-+ etc Just like you would batteries.
Connecting Capacitors
Snubber mod in place. Everything became very clean, but the sound is cold and hard compared to a 2A3 tube. It doesn't sound as hard and metallic as before without the snubber (but still with a lot of other mods). A lot better than before.
"Mr Blue":
https://vimeo.com/user3619914
"Mr Blue":
https://vimeo.com/user3619914
Maplins XM21X
Hi Guys those in the UK and Europe might consider the Maplins XM21X a 13.8v regulated supply capable of 9 amp peaks.
It is mostly used to power telescopes and there seems quite a few second hand on Ebay. I got one for £20 including postage which is reasonable as it is a weighty little $%£%$£$£$.
I haven't compared it to any other supplies but it is very quiet and seems to power my YJ boards well.
Now for a Sure Tpa3116!
Simon
Hi Guys those in the UK and Europe might consider the Maplins XM21X a 13.8v regulated supply capable of 9 amp peaks.
It is mostly used to power telescopes and there seems quite a few second hand on Ebay. I got one for £20 including postage which is reasonable as it is a weighty little $%£%$£$£$.
I haven't compared it to any other supplies but it is very quiet and seems to power my YJ boards well.
Now for a Sure Tpa3116!
Simon
Extra PS caps before the amp board never does any harm. I had a Meanwell SMPS supply that caused a nasty hum in the amp, added 10,000uf cap before the amp board and the hum went away.
To be honest I really do not like SMPS supplies (with a couple of exceptions they are not designed for audio) but adding some nice big caps does help them out.
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My 12au7 preamp to go with 3116d2
Just built a 12AU7 preamp to go with my blue/black 3116d2. It was a quick and ugly/dirty built using whatever I have in my parts bin
. Resistors were paralleled to obtain the value and wattage I needed. Chassis was salvaged from old satelite discrambler, using a piece of OAK for face plate. Schematic pretty much from the 4S preamp with Rk=2.3k, Rp=55k, Vg at about -6V with B+ of 288V. I use Wima MKC 0.47uf, 630v cap as output cap. Volume pot of 500k before grid.
Just built a 12AU7 preamp to go with my blue/black 3116d2. It was a quick and ugly/dirty built using whatever I have in my parts bin
. Resistors were paralleled to obtain the value and wattage I needed. Chassis was salvaged from old satelite discrambler, using a piece of OAK for face plate. Schematic pretty much from the 4S preamp with Rk=2.3k, Rp=55k, Vg at about -6V with B+ of 288V. I use Wima MKC 0.47uf, 630v cap as output cap. Volume pot of 500k before grid.Attachments
It definitely warmed up the sound, especially for vocals. I don't think the bias is optimized on the tube yet. I may change resistor to try out different load line/bias. The noise level of the preamp is very very low.
I'm sure you know most of the label means without reading chinese. The Mute one says pull "High" to mute. SD ones says to pull "Low" to cutoff the amp. The GND above Mute is for control circuit, while the GND at the far left is for input signal. The other pins are self explanatory for connections. Hope this help.
I think you have to refer to the datasheet as to what voltage is for the logic High. I have never needed to mess with those pins and you may not needed either. I'd suggest to leave those control pins alone to get start with. If you do need to play with those pins but with uncertainty, I'd definitely use a 2k or higher resistor to pull pins high or low and use a voltmeter to measure the pulled voltage at the pins to determine if they are in correct range.