Thanks Salas; I am waiting on a reply from the vendor to that question.
Where does this little buffer magic all the extra information from that is now coming out of my speakers???😀
Well, my pre-amp has been in pieces over the last few weeks, and I have been listening to the headphone preamp in my DAC as pre-amp for the last few weeks, and the whole system has sounded mediocre at best.
Previously I had the old standard B1 buffer in there, powered by a cheapo eBay HK Shunt reg. It had 1K resistors in the signal path, as was the original spec opposed to the new, generally accepted 220R of the DCB1. I had a DACT stepped attenuator for volume and it sounded pretty good.
This new DCB1 is blowing my socks off. My stereo has never sounded so good. It's quite incredible this project. The bass is tight and reaches right out across the room - not boomy but tight and punchy, probably on account of the 220R resistors. I never thought I'd like bass described as tight and punchy - it was how they always described the bass from expensive bookshelf speakers that I never liked at all - I'm a 12" man all the way 😉 The treble is so detailed and not in the slightest bit fatiguing, and the mids have this bizarre level of detail - in songs I know really well, I'm hearing singers changing their body position and the actual physical movement of piano keys clattering underneath the actual piano, where I never could before. Really special stuff!
Big ups to Salas, CRT, Mr Tea-Bag and Papa Pass! A thousand thanks to you all.
Also, all hail the 2SK170 - there's 20 of them in my system so far - 4 in the RIAA, 3 in the shunt reg, 10 in the DCB1, 3 in the Lightspeed shunt reg, and soon to be more like 36 when I get Oliver's DAC boards , the Pass F5 and EC designs I/V stage fired up. Silly numbers thanks to Salas and Papa. Thankfully matching my own now.
Listening to Feist's Let it Die, Steely Dan's Pretzel Logic, Tom Waits The Heart of a Saturday Night and Belle & Sebastian's Dear Catastrophe Waitress All awesome albums, by the way.
Even the wife had to humour me in admitting it sounded better!
Previously I had the old standard B1 buffer in there, powered by a cheapo eBay HK Shunt reg. It had 1K resistors in the signal path, as was the original spec opposed to the new, generally accepted 220R of the DCB1. I had a DACT stepped attenuator for volume and it sounded pretty good.
This new DCB1 is blowing my socks off. My stereo has never sounded so good. It's quite incredible this project. The bass is tight and reaches right out across the room - not boomy but tight and punchy, probably on account of the 220R resistors. I never thought I'd like bass described as tight and punchy - it was how they always described the bass from expensive bookshelf speakers that I never liked at all - I'm a 12" man all the way 😉 The treble is so detailed and not in the slightest bit fatiguing, and the mids have this bizarre level of detail - in songs I know really well, I'm hearing singers changing their body position and the actual physical movement of piano keys clattering underneath the actual piano, where I never could before. Really special stuff!
Big ups to Salas, CRT, Mr Tea-Bag and Papa Pass! A thousand thanks to you all.
Also, all hail the 2SK170 - there's 20 of them in my system so far - 4 in the RIAA, 3 in the shunt reg, 10 in the DCB1, 3 in the Lightspeed shunt reg, and soon to be more like 36 when I get Oliver's DAC boards , the Pass F5 and EC designs I/V stage fired up. Silly numbers thanks to Salas and Papa. Thankfully matching my own now.
Listening to Feist's Let it Die, Steely Dan's Pretzel Logic, Tom Waits The Heart of a Saturday Night and Belle & Sebastian's Dear Catastrophe Waitress All awesome albums, by the way.
Even the wife had to humour me in admitting it sounded better!
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Happy you liked it. Cheers. Its not just the 220R BTW. Its the Mosfet regs teaming with the sweet spot for this CCSed source follower classic topology, and DC coupling. The power source modulated by the signal is what you actually experience by any audio electronics stage. DCB1 is holistically voiced to taste, in my system (vintage English Walker sprung TT, Mission 774, Denon 103R cart, my Simplistic njfet Riaa, own design 6V6 valve line & KT88 trioded PP to my 95dB 2xTB, PHL, Audax, slim tower 3way lossy closed box spkrs). Of course after some feedback from the black pcb build thread's members deemed my further proposed mods positive, those are included in the Blue. In general I don't incorporate lightly tech ideas that may look fine on paper but can move the equilibrium of the tone I am after. I go slow and real life test. Blue is a special edition including the filmcap and hotrod mods in better quality, heavier copper board. A small resume of what the Blue DCB1 is about, for those new to the concept that missed the long black pcbs threads. I hope it was short and informative enough. Happy listening!
Hi,
for the input impednace, as it is R2R ladder. it change from point to point . 22K - 15k - 8k and go back to 15K
regards,
This is the reply from Diygene about his remote control stepped attenuator. Would it be suitable? Thanks in advance. Ditto what Lucas said.
Marra
for the input impednace, as it is R2R ladder. it change from point to point . 22K - 15k - 8k and go back to 15K
regards,
This is the reply from Diygene about his remote control stepped attenuator. Would it be suitable? Thanks in advance. Ditto what Lucas said.
Marra
Bit of a contradiction with the RC stepped VC.
Diygene on ebay say it is 22k max while Diyclub state that it is higher than 25k.They are both selling the same bit of kit with diyclub being the cheapest.I guess it depends on how much above 25k it goes.
Diygene on ebay say it is 22k max while Diyclub state that it is higher than 25k.They are both selling the same bit of kit with diyclub being the cheapest.I guess it depends on how much above 25k it goes.
Lovely valve amps Salas. Love the wood and varnished copper look on your pre-amp.
Strange for you to mix so many valves and 2SK170s. They are both excellent but such different philosophies and technologies. Do you feel any contradiction in approach, mixing them both up from stage to stage?
Strange for you to mix so many valves and 2SK170s. They are both excellent but such different philosophies and technologies. Do you feel any contradiction in approach, mixing them both up from stage to stage?
No. Jfets are solid state pentodes sans heaters to me. Since the DCB1 voicing is reported correct for other full SS systems too, logically there is no idiosyncratic issue.
All I was trying to ask is, if you are into both tubes and fets, how do you decide whether to do a particular stage in solid state or tube? For example, RIAAs have been made really top notch reference grade in both jfet and tube - same for pre-amps, same for power amps. I just wondered whether it felt a bit subjective that from stage to stage you are using both? Obviously not. I'm sure it sounds most excellent.
In my case its anarchic. It basically dawns on me I want to try something. Jfets lend themselves easier to projects that more can easily duplicate though. I mix Mosfet HV regulators in my valve circuits too.
Nice! This looks like a straight line version of the Mezmerize layout I am listening to right now, and there is no crosstalk on that. If the tracks are isolated, even by a gnats, it may look worrying, but it actually works fine.
Are you going to print a few of those? I would be interested in one if you are! There seem to be no power connections yet though?!?
Are you going to print a few of those? I would be interested in one if you are! There seem to be no power connections yet though?!?
Hi Lucas....yes same as mezmerize ..not many options...🙂.
Glad to hear that feedback, i remember reading a comment by Douglas Self on the layout of the switches of his preamp that made me think about this spacing of signal tracks.
Unfortunately the pin spacing on miniature relays is not good for this.
I'll post my final boards here ( Sprint files ) so you can use them if you like, my board will include the mute and on/off relay as well, it's 209 mm wide so as to fit a hifi 2000 small box perfectly ie: back of box has only one board with all connections, gives clean layout.
This is my draft...might change a little before i finish, namely might not need all that space por the dcB1 ac switching relay.....my tranformers are in remote box.
Glad to hear that feedback, i remember reading a comment by Douglas Self on the layout of the switches of his preamp that made me think about this spacing of signal tracks.
Unfortunately the pin spacing on miniature relays is not good for this.
I'll post my final boards here ( Sprint files ) so you can use them if you like, my board will include the mute and on/off relay as well, it's 209 mm wide so as to fit a hifi 2000 small box perfectly ie: back of box has only one board with all connections, gives clean layout.
This is my draft...might change a little before i finish, namely might not need all that space por the dcB1 ac switching relay.....my tranformers are in remote box.
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Hi Salas,
No, did not try it yet, but it's awfull close to the output terminals......220V i mean.
At least with the secondary ac only, voltage is lower so induced 50hz hum , if any, should be much lower.
I would like to fit it all in....would make a nice clean unit.....🙂
No, did not try it yet, but it's awfull close to the output terminals......220V i mean.
At least with the secondary ac only, voltage is lower so induced 50hz hum , if any, should be much lower.
I would like to fit it all in....would make a nice clean unit.....🙂
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It really makes a lot of good sense, how you've laid it out. I also like what some of the commercial amps do, using a thick strong PCB and incorporating the RCAs in PCB mount form, which then poke through holes in the chassis. A vertically placed PCB works best for this, as it is much stronger then, bolted to the back wall of the chassis.
Otherwise, wiring from the relay board to the RCAs in damned fiddly if trying to keep cabling short, I've found.