Tinkering with the office rig.....

heiney9 · June 24

Let me know Ivan. I am interested, but not in a rush

Thanks

H9

pitdogg2 · June 24

heiney9 wrote: »

Let me know Ivan. I am interested, but not in a rush

Thanks

H9

Will do I'll get it tested and get back to you.

heiney9 · June 27

This little rig is laughably good not only from a fun factor, but everything sounds so good. One of the best sounding office rigs I've put togther.

Reality is; the next step will be my own ACA mono's, but that has been pushed to a Fall/Winter project. Just too much else going on during the Summer.

H9

HzTweaker · June 28

Glad you're enjoying it! Sounds like it.

I'm digging my little setup as well.

heiney9 · July 15

I received a 1965 Russian 6H8S, a military tube made at the Proton factory. Damn this is a nice sounding tube. Perhaps a bit light on the lower bass notes. If it's new as stated, may need more break in.

I am a bit surprised at how different each 6SN7 variation sounds. To be honest at this stage (still early) I am not that impressed. I've acquired a wide range of the better to best reviewed and only a couple really hold my interest.

Could be the pre-amp they are used in, could be the dac implemented in the pre-amp. Don't get me wrong everything sounds very, very good........but nothing really blows my skirt up using the Schiit LYR 3 as a pre/dac.

Perhaps I'm too picky and am expecting too much from such a modest rig. I try to temper my expectation vs. the big rig. I'm getting close to $300 in single 6SN7 tubes w/shipping, etc and haven't yet found that "it" sound. I am close to done purchasing 6SN7 tubes. I have all the "good" ones at this point.

Still have a couple to audition and one or two that need more auditioning.

Next step with the Schiit LYR3 is to bypass the internal dac and use my modded Eastern Electric Mini-Max DAC PLUS. But now I'm starting to get too many cables and more gear taking up space, etc. I went from ultra simple to now more complex, but I have to see if the internal Schiit dac is the weakness or if this well regarded HA/PRE just doesn't do it for me.

Last week I ordered (4) more Burson V5i hybrid op-amps to use in the Keces DA-152. That's the unit I was having issues with sound cutting out and I think some distortion. I originally replaced (5) op-amps with (4) discrete op-amps; (2) Bruson V6 Vivids and (2) DEXA Ultimates and (1) Burson V5i hybrid.

The Burson V6's are just too power hungry when running the other (3). She was running out of juice to power all those op-amps. Now I'm running (3) Burson V5i hybrid's and a pair of DEXA Ultimates for the dac section.

Spent a couple hours last night listening. WHOA! Did that sound really, really good. The sound stage was huge and the space between instruments and vocals was superb. Top is slightly rolled off, but they aren't close to being broken in.

The LYR3 is not giving me that 3D projection, it's rather flat except with a couple of the 6SN7 tubes, but even then it's nothing like what I heard last night.

The Keces DA-152 w/old school Burr Brown PCM 2702 chipset is sounding pretty fantastic.

I have done a lot of listening with a lot of configurations lately. Some are excellent some are very good, some are better than they should be.

The one constant is the little Pass ACA is a little gem. Amazed at the high quality of performance and sound from just 8 wpc and the R200's are not super efficient for that 8 wpc.

But, this is the fun part for me.

H9

heiney9 · July 15

heiney9 wrote: »

This little rig is laughably good not only from a fun factor, but everything sounds so good. One of the best sounding office rigs I've put togther.

Reality is; the next step will be my own ACA mono's, but that has been pushed to a Fall/Winter project. Just too much else going on during the Summer.

H9

When I said this I was listening using the 1954 Sylvania JAN CHS 6SN7WGT chrome dome short bottle, black plate tube. The best 6SN7 I've heard so far. In fact all the older Sylvania's sound excellent.

After further consideration the Keces DA-152 with the new op=amps may sound even better.

H9

pitdogg2 · July 15

In fact all the older Sylvania's sound excellent.

You'll get no arguement from me. I think Sylvania really nailed the 6sn7 tube in general.

heiney9 · October 8

Still messing around. I haven't started to build my Pass ACA mono's yet. That's the first Winter project. I did manage to purchase another (fully built) Pass ACA to see how they run as mono's. This one as the first one has the upgraded parts (called the Tungsten Audio mod), so they are equal builds.

I'm running them in parallel mono and boy did that really increase the WOW factor. Double just about everything and now they play with a bit more gusto and a tad more clarity.

These simple amps have no business sounding this good. Granted at today's prices they aren't exactly budget. But at the same time I think you'd have a hard time finding mono amps in the $600-700 range that sounds this natural, open and grain free. The clarity is astounding and they are dead quiet w/an expansive sound stage, bass is excellent.

Even the single amp for nearer field listening on efficient speakers is a real treat. I was asking a lot of the single stereo amp in medium sized room, seated 8ft away playing at a fairly loud level to fill the room.

I am itching to get a linear power supply for each to see if that improves further. Not a fan of switching supplies even though Nelson picked one with good measurements and reliability.

China tariffs are scaring me off at the moment.....lol

H9

billbillw · October 8

If you are going through the effort of building your own ACA kits, why not build your own linear power supply? These things are really quite simple. For the low wattage of the ACA, I'd just build one dual channel ~24V-30V LPS with a dual tap torroid, a pair of 15K 35V filter caps for each channel, a 8 appropriately sized diodes, 8 Wima Caps for each diode, and a pair of decent film caps to run in parallel to the big electrolytic.
I did this many years back for my Pearl Phono and it was really pretty simple. Mine was tad harder because I wanted to run both DC channels in a single umbilical, but for those ACAs, you would obviously want separate runs to the amps. (Note: Later, I went back and added a ground wire to run through the umbilical and tie into the mains ground.)

(note: I'm pretty sure I mislabeled that and it should be 2x30V)
I'm not sure if the ACA needs a regulated supply or if they amps have regulators built in. For my Pearl, each channel of the preamp has onboard regulators to bring that 30V down to 24V if I recall correctly. If it needs a regulated supply, that's a bit more complex.

heiney9 · October 8

I needs a regulated supply. The switching supply is 24V 5A.

This is what is recommended and sold with the kit.

https://diyaudiostore.com/products/meanwell-24v-5a-psu-with-power-cord

I just think a LPS with an array of caps might give more reserves. It probably is a minor difference, except I see some of the guys on DIY audio claim a good LPS improves bass and dynamics.

The switching supply was used for safety and cost as the ACA is supposed to be a beginners build and not mess around with lethal voltage from the wall.

This is what I was looking at. I've bought from them before as I have a 19V 4A ZeroZone LPS for my Roon Nucleus One. Just trying to get an idea of the taxes/tariffs.

https://fyfaudio.com/products/hiend-zero-zone-3-way-ultra-low-noise-linear-power-supply-dc5v-dc25v-all-kinds-voltage-lps-3x-lps-for-audio?VariantsId=11638

I'd do (2) 24V 5A and (1) 5V to run my FIIO SR11 streamer.

H9

billbillw · October 9

I am very familiar with the ACA. I've tossed around the idea of building a pair for years. I just wasn't sure if they had regulators on the amp boards. I just checked the schematic and confirmed they do not. I still think you could build a DIY 2 x 24V regulated supply yourself for less than two of those linked above. It might take some digging around at DIYaudio to find a project and you may need to have the boards custom made, but the sum of parts should be significantly less especially with the $58 shipping cost for each on those from FYFAudio.
You could possibly use two of these boards and fill them to make a 24V output from each channel. https://www.fyfaudio.com/products/p3-wata-high-speed-dc-regulated-power-supply-bare-pcb-for-updates-cd-dac-preamp

heiney9 · October 9

billbillw wrote: »

I am very familiar with the ACA. I've tossed around the idea of building a pair for years. I just wasn't sure if they had regulators on the amp boards. I just checked the schematic and confirmed they do not. I still think you could build a DIY 2 x 24V regulated supply yourself for less than two of those linked above. It might take some digging around at DIYaudio to find a project and you may need to have the boards custom made, but the sum of parts should be significantly less especially with the $58 shipping cost for each on those from FYFAudio.
You could possibly use this board and fill it to make a 24V output from each channel. https://www.fyfaudio.com/products/zerozone-pass-crc-class-a-amplifier-schottky-rectifier-filter-bare-pcb-for-pass-amplifier

Not sure I have the capability to start messing will voltage that can kill.....I could learn....lol

I'd only have to buy (1) of that model LPS from Fyfaudio as it has (3) independent voltage banks. (2) of the output banks would be 24V 5A and the 3rd would be to power another streaming device I have @ 5V. You just tell them what 3 voltages you want.

That's what is so appealing about it.

I agree 100% on cost of parts if I have to buy 2 or 3 LPS, but a single 300V unit with (2) 24V 5A outputs and (1) 5V 2-3A output should be sufficient and not break the bank unless there's a high tariff on the unit. Still trying to find out what the tariff cost would be.

I just loose out on the self satisfaction of my own build and possible shock......lol

H9

P.S. the ZeroZone brand has proven to be excellent as long as you don't get "fakes". FYF Audio seems to have a good rep. I bought from them before and it was super fast, with good communication and you get exactly what's pictured.

The same is FS from many Ali Express sellers, but I don't trust you always get what you see in their ads. They'll show you a pic from a site like FYF Audio and then send you the same thing with crappy parts and shoddy workmanship.............not all, but some on Ali Express.

heiney9 · October 9

I will say the parts buying from Mouser or Digikey or PartsConnexion can be frustrating. I know this from sourcing certain items for a Dreadnaught/X-over build and from sourcing the Tungsten Audio mod parts for my ACA's. Even if you have exact part #'s.

One of the feet is missing on one of the ACA's.............christ trying to source new feet is a real PITA since they have hundreds to choose from....lol.

So that's turned me off a little bit from buying a blank board and going to town. Not to mention sometimes you have a minimum order #.

H9

billbillw · October 9

That "lethal voltages" is a bit of an exaggeration by Pass DIY. I think interviews with Nelson talking about the original Amp Camp in person event was meant to be cheap, easy, and done in one afternoon/day. They were using widely available laptop 19V power supplies for the cheap and easy portion.
These aren't tube amps. 120V will usually only give you a tickle up to the elbow. That's really only the wires between the mains in/fuse and the transformer. Once those are hooked up, its down to ~30V (if you pick the right transformer). That's still AC until after the diode bridge. Its really no different than poking around inside any 120V device, which I'm sure most of us DIYers have been doing for a long time.
But yes, buying is easier, and maybe safer...but quality wise, your own build would probably be far superior from choosing nice parts, and avoiding off brand China capacitors.

heiney9 · October 9

Yeah, we'll see. It's probably overkill as the Meanwell units sound just fine. Perhaps the $$$ spent on a built one or self build could/should be used for other audio purchases.

I'm pretty much making the dual mono ACA's and the Schiit Lyr 3 - tube pre/headphone amp w/dac my main office rig. It sounds so damn good! The clarity and separation is just crazy good!

This is the pre/dac I truly want to run, but finding them used in the US is few and far between. Too much money new for this kind of rig. If I could pick on one up used for $800 or less I'd do it.

https://power-holdings-inc.com/Keces-S3-DAC-Headphone-Amplifier-&-Preamplifier-p137031938

Before the pandemic these retailed for about $1100 or less. I've missed sales in the past of used ones for $550-650.

Or maybe just stop and enjoy what I am currently running. I bought so many 6SN7's to find the best sounding one for the Lyr3. Abandoning it probably doesn't make sense.....lol.

H9

P.S. the ZeroZone LPS comes with Nichicon FG caps, not cheap Chinese off brands. I agree, avoid those.

heiney9 · October 17

A few more changes, or rather moving gear around. I am using the Schiit Ly3 as a pre-amp only because the AKM dac card is lacking. I replaced the op-amps in my trusty Keces DA-151 and am using that as the USB dac.

Viola opened everything up even better. Today I was searching on the 'net for the values of the coupling caps used in the Keces, they used some nice film caps. I want to replace them. An old thread of mine came up in an AI Overview in which AI stated I was mistaken about the 4.7uF coupling caps....whcih I was not.

Here's the AI Overview in Google:

AI Overview
The KECES DA-151 DAC
does not use coupling capacitors in its signal path. The device features a "Fully DC Coupled Circuit," meaning there are no capacitors used to block direct current and pass the audio signal. This design is intended to prevent "signal distorting capacitor" and provide a more neutral frequency response.
This design detail is relevant for audiophiles and DIY enthusiasts because:

Audio quality: The absence of coupling capacitors can eliminate potential distortion or coloration they might introduce, which is considered a desirable trait in high-fidelity audio equipment.
Upgrades: Since the DA-151 lacks these components in the signal path, replacing "coupling caps" is not a valid modification. Upgrades to the device would instead focus on other components, such as the op-amps or power supply capacitors.
User confusion: The search results indicate that some users have mistaken other capacitors in the unit for signal-path coupling caps. For example, a user on a Polk Audio forum discussed replacing 4.7uF capacitors in their unit. These would be related to the power supply or other parts of the circuit, not the signal path.

Wrong....lol. AI has a way to go. The Keces DA-151 MKII eliminated the output coupling caps, the original 151 has them.

More on the new configuration of gear later.

H9

heiney9 · November 1

I've added/swapped in a new piece of gear. These have been out of stock at DIY Audio store for awhile. Just recently back in stock.

But I found one already well built for a decent price from a great seller. This thing because of the Nutube needed to be well packed. The seller did a stellar double box with 4" of bubble wrap and shipping peanuts.

Pass Korg Nutube B1 pre-amp.

FIRST WATT B1 PREAMP WITH KORG TRIODE

Running a pair of Pass ACA Class A mono blocks- about 20wpc.

Sounds so fantastic, can't get enough. Haven't messed with the 2nd harmonic adjustment yet.

H9

heiney9 · November 1

double post

Tinkering with the office rig.....

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