Forgot a few things. I use DietPi, and have reconfigured the CPU and overclock plus turbo settings, decreasing both temp and strain on PSU, also reducing noise levels. Had a slight effect too. At least I think so… 🙂 I love bias. Cognitive ones too.
I’ll check out those speakers of yours too
(1) Where did you get those speakers of yours? I saw the drivers but not the cabinets. It looks like a fun project indeed.
(2) The ADS L810's are very fine vintage speakers but they are commanding some crazy money nowadays so you have to be extremely careful with the flippers. And option would be the L710's or the L500's. I've had mine since new (OK, they were the store's demo... long story) so they are in extremely good shape. But I haven't seen anything like them. In any event, they are efficient, lack the soundstaging of modern designs but they have a fine tonal balance and are very non-fatiguing to listen to. I will listen to them and then I'll swap back to the Maggies.... I have a DIY F5 on the 810s, right now I swapped in a rebuilt Marantz 2325. The Maggies (1.7s) are on DIY A2 monos. I got the B1Korg as a back up.. I tried it with the F5 and it sounded fantastic.
(3) Wow, it sounds (pun..) like you've gone out with your Raspberry. I've just used the USB port to a NuForce HDP4 and uDAC2/3. The former has it own power supply so it works really well. I've had it for years now, and even then I got it used but it was never a cheap unit. Other than that I use one for development ( vi, grep, gcc ) prototyping and LAN duties, the other two (USB3) are for my prototype NASs. Plus I got the motor kits and what not, for that I wrote some simple Python scripts. It's neat turning lights ON and OFF across the house with the CLI.
So many toys, so many amplifiers, not enough speakers... only one life to live!
I see some builds here with substantial power supplies. Has anyone had the opportunity to compare the stock store kit to one with an upgraded power supply?
Hmm.. the schematic would require FOUR resistors, huh? It looks like you got 2.... Looks like one of your outputs is directly wired (the one on the picture's right), the other goes through the 1K.
Looks nice! How do you like the Stealth caps? I just picked up 6 from the swap meet.
I was thinking of putting a power supply in a similar sized chassis to the B1 Korg Nutube kit chassis. Is that a 50va 22v Antek transformer?
Yep, please use the search function, I posted on this.
SMPS (not as per kit as the kit didn't exist then but similar) vs huge linear regulated lab supply.
Bottom line in my case: with upgraded PS caps (very minor benefits either case) I prefered the SMPS overall. The lab supply had though a very slight edge in the bass, but was (slightly) beaten elsewhere if I remember - was ages ago, details are though in my post. Once I fitted Mark's excellent SMPS filter, the SMPS beat it in any department, quite a clear cut, though slightly as playing with the power supply made less changes than for example replacing the caps in the signal path...
All IMHO, but for me there is little to be gained replacing the PS. You can slightly tweak it and concentrate then elsewhere if you want: Papa did an amazing job. The more I play with Class A, the more I believe SMPS is made for it (and for Class D for completely opposite reasons). That's probably due to the constant load draw. You only need to make sure you have A) a proper filter or filters with say inductances that really filters out garbage from a few kHz to the MHz range (depending on the device, it might be sensitive), B) for some reasons some additional very low ESR decoupling PS between the SMPS and the device (again, some devices being more sensitive than others). All IME, including recently if speaking Papa's units with B1K and the VFET amp.
But then this is DIYA - it is fun to experiment and to have your own findings!
I hope this helps
Claude
Caps are nice. I could tell a big difference switching from the 10uf Elna’s I had.
The transformer will depend on your power supply you use. The Sigma o11 requires a 24V secondaries and I used a 50va. I didn’t compare it to the SMPS though so cannot comment on the difference.
tony, do you have a picture example? I built a Tubes4hifi preamp that used the same method of 1K resistors across the outputs but only used two (one per side).
I just looked at the schematics and the picture he posted. Mine only has one output pair.
Here's where I am currently at with my B1K, I fall more and more in love with it every day.
All resistors are Takman REY, Tepro RA, Vishay Dale CMF, or Vishay Dale CPF3. Wiring is all PTFE silver plated, shielded everywhere except the short run from the volume pot to B1K inputs.
Film capacitors are Miflex KPCU-03 and Mundorf Supreme. I've used both models in different tube projects and they are fantastic. I prefer the Miflex a bit, but the 1.0uF and 4.7uF would have been absurdly large and unable to fit in the chassis. Electrolytic capacitors are Nichicon UKA series 1000uF 50V, I put some Kapton tape over the top of them since they come right up to the top of the chassis. I may swap them out one day for UKA 1000uF 35V as they are a tiny bit shorter, but no rush there.
On the PSU side I have a separate matching modushop chassis with an Antek 25VA 25VAC transformer feeding a regulated PSU I found out of China and one of Mark Johnson's PO89ZB DC filters to clean up things even more. The regulated PSU isn't great but scopes with less ripple and noise than the wall-wart, I hopped into a group buy for a Salas Ultra-BIB and will drop that in once I have it in-hand.
Besides the Ultra-BIB, upcoming plans are an Eizz 50k stepped pot that's somewhere in the mail. I've debated perhaps upgrading the RCA jacks but still undecided as of yet.
All resistors are Takman REY, Tepro RA, Vishay Dale CMF, or Vishay Dale CPF3. Wiring is all PTFE silver plated, shielded everywhere except the short run from the volume pot to B1K inputs.
Film capacitors are Miflex KPCU-03 and Mundorf Supreme. I've used both models in different tube projects and they are fantastic. I prefer the Miflex a bit, but the 1.0uF and 4.7uF would have been absurdly large and unable to fit in the chassis. Electrolytic capacitors are Nichicon UKA series 1000uF 50V, I put some Kapton tape over the top of them since they come right up to the top of the chassis. I may swap them out one day for UKA 1000uF 35V as they are a tiny bit shorter, but no rush there.
On the PSU side I have a separate matching modushop chassis with an Antek 25VA 25VAC transformer feeding a regulated PSU I found out of China and one of Mark Johnson's PO89ZB DC filters to clean up things even more. The regulated PSU isn't great but scopes with less ripple and noise than the wall-wart, I hopped into a group buy for a Salas Ultra-BIB and will drop that in once I have it in-hand.
Besides the Ultra-BIB, upcoming plans are an Eizz 50k stepped pot that's somewhere in the mail. I've debated perhaps upgrading the RCA jacks but still undecided as of yet.
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1: I bought the Super Pencils used, with Alpair 12Ps in them. Build quality not very good, and 12Ps over-driven. So I replaced the drivere this weekend. Now entering an extremely lengthy burn-in process. Check out the Frugal website, Frugal-phile.com or something like that, if interested. Kits are also available, and I am aiming for a braced kit version in the future.
2: Sounds like superb speakers you have. The 12Ps are revealing as hell. But I finally feel my front end is good enough. Several reasons, but the RPi mods were not insignificant wrt midrange and top end smoothness.
You have a lot of equip. That is very nice. It enables a great deal of experimentation and comparison.
🙂
That's an understatement.... I think I'll check those speakers of yours. I've been thinking of trying out some high efficiency widebanders for eons.
BTW, just to give you an idea of the current irrationality of the used vintage component market. My 45 year old ADS L810's fetch more than my flawless rosewood, 20 years old PSB Stratus Gold-i's in the HT.... even though the PSBs will walk all over the 810s. It will be NO contest, trust me.
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Be sure to check out the other Alpairs too. Planet10 and Scottmoose here on the forum are the prime resources for everything regarding these drivers. The 12Ps in super pencils provide slam and good overall response. But there are other drivers and solutions that will give more fine detail and finesse. Had I not had the enclosures allready, I think I would have tried one of the smaller Frugal Horns. Next time 🙂
KJF audio sells kits with literally everything, and matched drivers. UK based. But there are similar companies in the US. I think Madisound, if I remember correctly.
regards,
Andy
