Thursday, May 20, 2021

Lapping Whale's Tail In GR8 Spring Conditions 20May21

Before this coming closing weekend Steve & I decided to hit Breck for a likely final outing. OMG, conditions were excellent and TBar & Imperial were open so we basically lapped Whale's Tail all morning, though we did take some side adventures too. The cornice atop Whale's Tail wasn't too bad ~8ft. Gorgeous 60° weather, perfect corn and soft snow and even some fresh track runs for us made the outing well worth it. At times it was like surfing. I wore shorts but you can't tell. Of course we stopped at ORB on the return home. They are running no masks for the vaxed and even are again allowing tasting before buying. Ahhh.

Wednesday, May 19, 2021

Nest Theater Part Sixteen - Rollin' The 300B Power Tubes & The Rectifier 03May21

Well almost six months have passed without a hardware update to the Nest Theater ~ so it's time. :) Everything is working very well; the NestT sounds spectacular - as attested by me and others who've listened. Especially strong reproduction is heard with acoustic and vocal material - the Fostex drivers and 300B SET amp shine there. Maybe that's the no feedback, 8.5w of pure amplification from the power tubes or my back loaded horns. Whether playing high rez files from the JRiver Win10 PC or low rez from YouTube, it sounds great. Even my Harmony remote control has been dialed in nicely and does what I want. I guess my only complaint is that the amp and dac are not remotely controllable. I have to manually/mechanically turn on the 300B SET amp and the Denafrips DAC. These are not big deals but remote control would be nice. Others might say my lack of use of vinyl is a drawback of my system, but that was intentional and for convenience and does not detract for me one iota. Before we get on with the big show, here's the amp before changes...


Let's first talk about the rectifier...I've never believed the rectifier tube choice would make much difference so I hadn't swapped it to date. However, a number of believers swear by one particular tube that can make a smoother delivery. I have acquired that tube, a 1957 NOS Sylvania CHS5931. This is a premium 5U4 design and has replaced my "stock" 5U4, a currently manufactured Shuguang 5Z3PJ. The swap does sound smoother and seems a smidge more dynamic, but who knows exactly - it made little difference on the measured SPL response curve or on impulse response measurements. It's in there and I like it.
Let's get on to the main topic of this part's mod ~ tube rolling the 300B power tubes. I currently use the musical Russian Gold Lion 300Bs and am satisfied. But when is good enough, good enough in the audiophile realm? So, rather than plunking down $10K for a pair of 1950's Western Electric 300Bs new from old stock (NOS), I sought the better of currently manufactured 300Bs. Fortunately 300Bs are still part of many fine audiophile amps and therefore manufacturing is reasonably strong - but the companies are making bank on these things. There are even higher wattage versions now but I sought the classic 8.5w tubes given my highly efficient DRC BLH 94dB speakers. Here is a pretty long list of contenders (priced by matched pair)...

BrandModelPrice/PairCountry
EAT300B$1,700Czech Republic
TatasukiTA-300B$1,600Japan
Western Electric300B (reissue)$1,500USA
ElrogER300B$1,325Germany
Emission Labs300B Mesh$950Czech Republic
KR Audio300B
$800Czech Republic
PsvaneAcme Series 300B$830China
LinlaiGlobal E-300B$630China
Shuguang300B-Z Black Treasure$540China
TJ Full Music300B Mesh Plate $380China
GenelexGold Lion PX-300B$280Russia

I dove on many reviews of these tubes and sought the flat and great sounding, but not whackily priced, and chose some more durable tubes. Unfortunately I could not trial them with my specific amp and speakers - and match to circuit & system is important - but these tubes have the correct specs for my amp build - NP. Since I have Russian Gold Lions already (warm and musical),

I sought tubes built in other countries but read the Western Electric reissue from the US was not up to snuff. I chose to get both a Chinese pair and a Czech pair as they supposedly would allow contrast of a classic WE 300B design/sound with a more modern 300B design/sound. The Chinese TJ Full Music is the same as the Sophia Princess mostly and they're the Chinese originals, heard to produce the classic mid-range sound. Pretty underplayed packaging.

 
The Czech KR Audio is a modern design with heavier and taller glass, heard to be wider, flatter and more dynamic; it was regularly lauded for pure sound throughout the spectrum and it's robust build, and I liked the solid plate (vs another "mesh"). The KRA easily had the best unpacking experience with a nice box, foam insert and included a test measured output for the matching pair.
 
The Japanese Tatasuki or German Elrog would've been there, but I couldn't hack the prices. Too, EAT is a marketing ploy. So, on with the show... I turned off the supertweeters and sub and just drove and measured the BLHs driven unadulterated by the amp/dac. I used REW to take frequency sweep SPL measurements of each of the tubes.. And of course I audited some favorite tracks with the three tubes. The Gold Lion was warm and comfortable with a great mid-range response. The TJ Full Music about the same dynamically and frequency range but much smoother resulting in a larger rendered soundstage to my ear. The KR Audio had a tighter bass and better extension at high end. The differences are more subtle than I'd expected and the similarity in shape of the SPL frequency curves shows how the speakers really dominate the sound reproduction. I preferred the relatively bigger sound of the KRA on most tracks and they remain in the amp for now. They are definitely more fun for me on electric rock tunes - the Killers new album spoke to me but I didn't want for subtleties when playing Molly Tuttle or Reina del Cid.
To assure I apply the best filters to the "new" system with the Sylvania rectifier and the KRA 300B tubes I restarted the sub and supertweeters and remeasured the complete system using Dirac Live and set up new filters in the miniDSP DDRC-22D. It was a smidge time consuming to take 13 measurements but the resulting sound is worth it. Green sweep is the new corrected response vs the old corrected response in blue - better fit to my target home curve.

Steve helped audition the new tube setup. There's more listening and perhaps tweaking to be done but the upgrades, while somewhat subtle, are present. Finally, here's the "new" amp in with the rest of the gear in the "rack" - I need to do something about hiding some cables in back. Kala will also be pleased to "hear" that I really don't think I can do better; by "hear" I mean the explanation and that I probably won't take the NestT further into audiophilia and not the actual "hearing" right beneath our master bedroom.

UPDATE 06Jun21 - While in Summit I took some time to re-roll the new 300B tubes and perform complete equalization and re-measurement of the system. Below, the only variant is the 300B power tube: green is Gold Lion, orange is TJ Full Music and blue is KR Audio. I also re-listened to key tracks from The Killers, Molly Tuttle, Reina del Cid, Phoebe Bridgers and Dire Straits to cover the gamut. My conclusions are similar to my initial assessment but I must say the TJFM tubes are very smooth and render acoustic pieces phenomenally well. The Gold Lions too are not slouchy, but are clearly eclipsed for me by the others, especially on dynamics. Again the KRAs are best, they really deliver tighter overall bass and yield great punch in rock pieces without suffering on the quieter voice and acoustic stuff. They are also quieter than TJFMs, but that's not audible at playing volumes anyway. Again I am struck by the relative similarity of these SPL vs frequency curves - indicating how clearly the Fostex driver and DRC BLH cabinet design dominate performance. I've set up filters on the Dirac such that if I change tubes I can simply select a different filter set which is matched to that power tube - but the KRAs will see the bulk of the duties.



Tuesday, May 18, 2021

Fresh Tracks On The East Face 18May21

Whoa, it snowed last night above 10Kft elevation and Steve scored us "medallions" to ski ABay gratis today. No reservations, no masks, fresh snow, runs @ ABay... what's not to like. It is spring so we targeted a 10am start and hit that exactly - we finished a little after noon for a beer on the beach. But first we scored a number of fresh runs - the best of them traversing out on the east face. Skiing was springtime good and we hit all the open stuff; Pali had recently closed. Great day with my ski buddy but the beach was not raucous at all today.







Monday, May 17, 2021

Through Denver - See M&A Place And Visit Comet Brews 16May21

I dropped Rob at the airport painfully early on Sunday so he could finally get some sleep. Kala and I were headed to Summit so chose to stop in Denver for a visit with Matt & Alexa at their new apartment in The District. We had a nice visit with M&A and enjoyed the tour of their new, larger, finer place and Matt's new driving sim rig.. They even have two covered parking spots below their place and are in walking distance of the famous 50 year old Denver bagelry, where they took us for breakfast. We also took the chance to taste an excellent lager at one of their favorite breweries - Resolute's unique and very tasty salted lime lager, Crispy River is even available in cans but on tap was outstanding.

Then, in Littleton we visited Comet Brews to meet an old friend and new father and brewmaster Brian Wilke. Fortunately his family was able to stop by too - Nelse is a tall and very happy kid - a Godsend for Brian & Lisa. I dropped off a set of audio gear that may become part of the brewery sound system (Adcom gear including amp, pre-amp and disc changer). We discussed how to run speaker wire but else just talked. B&L are holding a grand opening soon after a year deferral due to covid and other. Comet is not messing around with pilot batches - they went right from home brewing to full production. Great to see Brian and his total environs - how he keeps all that together with a full time software job at Amazon is amazing.

Saturday, May 15, 2021

Spring CoWW Outings 13May21-15May21

Wow-wow-wow, we had a great several days on the Front Range waters fishing, solving world issues and sharing again with good friends. Different groups of CoWW fishermen grouped to fish the 11 Mile section of SPlatte, then the PT section of Arkansas and finally the BHSC section of Arkansas. We (Rob, Dave & Jim) started at 11 Mile and completely crushed it. Everybody had many cutbows & rainbows, some cuttys and a couple browns, including some larger ones like my 22"er or Jim's big fish. I had the best day ever on @ 11 Mile with over thirty fish! I had so much Hero cam footage that my battery died and I had to use a camera and one-hand the shows. We had a blast fishing the last "campground" section (though it's not open yet) of the river here, all armed with Rodfather builds. Flows are still just 63cfs and bugs were evident but not epic - midges worked best in the AM and the BWOs worked best mid-day, then we were back on the midges later in the PM. We capped the gr8 day at Cerberus meeting our MIA CoWW, DD, there - great food & brews. Yeah, the brewery pic is a bit fuzzy - as were we.

 
After sleeping very soundly we hit it again on Friday - this time with Rob, Jim, Dave and Andy Holley all riding in the Crusher Too to Pueblo Nature Center, and meeting us there from Salida was the mighty Lehmann. Flows were up 3 days ago to over 350cfs but holding pretty steady, and the water was oddly gin clear at the new levels. Despite the good viz and decent later spring flows, we saw just AM midge sign and sighted not as many fish as typical for this area. Greg caught the most by changing tactics all day and oddly the rest of us had a very high number of remote releases. Andy won the best plan well executed with a nice targeted cutbow catch on the way back to the car ~ well done. While it was kind of frustrating with a modest catch, there was other stuff going on. We competed with a giant raptor at one hole and I swear he was yelling at us to move on on occasion. We also were treated to a gaggle of goslings (16 kids). We even crashed the Pueblo nursing school graduation event at Brue's while we waited (a long time) for our table. Another good beer and bar food venue (green chili sloppers were the ticket).
 
Undaunted by the thin Fri catch and bolstered by a full evenings' rest, Rob, Greg & I hit the freestone section of the Arkansas while Jim & Andy played golf. We started below Coaldale at Lone Pine and moved up to Canyon Trading, still below Coaldale. Everybody was blanked that morning in fairly stained water; flows were fine @ ~260cfs but what we saw while passing Hayden Ck told the tale of runnoff as this tributary is running very chalky. Frustrated with the AM result we headed to the always tasty Amica's pizza in Salida for an early lunch - and then even stopped at Salida's new brewery, Tres Litros, for a good hazy IPA. Re-invigorated we headed down to Salida East determined to right our wrongs, and at least I got a couple standard browns on my full pass of the area. While the CG is open, there weren't many fishermen at all and the sites seemed more filled with kayakers. Rob & I closed the day with many beers in the Blodgett theater room and playing "YouTube music & comedy education challenge" between revealing thoughts. A weakish day closed strongly.
What a blast it is to go fishing with the CoWW.