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Met the man, the myth, the legend, Sir Stretch! Had a great lunch with him and Al. He lives up to the hype! We only have the two, but we switch with each other every week. Also made a trip to Ikea with Al. I needed an armoire for my clothes because I'm gay! Al not only helped me pick them out but stayed and helped put everything together. He's either an extremely good friend or extremely bored. I think maybe both!

Yay ! I got music, and no background noises even at max volume. No Hums, no hiss !! Oh my gawd! I am blessed by Dr. Kevin Gilmore!. I appreciate it so much sir Dr. Gilmore! Finally, I have reached my “ultimate dream goals!” With very limited knowledges. Thank you to George for making this Build a possibility!! Thank you so much to the community as a whole. The best Stax community out there ! Finally, some pictures, herself and in all her glory. Pure solid silver for wires . I am big fan of it I am smiling like a maniac! Yayyyyy! stacking up, and Amp is 130F, the PsU is 141F after 2 hours. Pretty warmth ! Can’t imagine the original The most beautiful amp I have ever had! Period. Time to “burn-in”

Yesterday: finally moved all the way out. I’m back in Tennessee now. Everything (hopefully) will be finalized this week, but everything that we are keeping from the house is in transit and everything else has been arranged to deal with. There’s now about 3x what is reasonable in my tiny apartment and 10 uhaul uboxes on their way to Tennessee. Now to find a house on this end.

I helped this guy move into his new place in Mayberry.

I am getting very close! Thanks god that @Kevin Gilmore , @Georgep , @Soren, Birgir, Mike, and the whole community here. Especially thanks to Kevin for taking up your time and advises, and thanks George for the chassis, some obsolete sands and sharing hard to find Xicon. I finally realized that adjusting the batteries with 10k pots is wrong, and it will in the end make 1 battery stuck. Have to measure 22k resistor to 6.5V and then dialing with 2k pot to 740V . Thanks George for the method and it worked to unstuck my battery Now, I can have all 4 batteries at 740V, O+/O- is -100mV to +50mV on right channel. -200mV to +12mV on Left channel. This is cold start O+ to Ground References is R (2.2V and dropping steadily) and L (4.5V and dropping steadily) I think my next step is to plug in the 009 and try to observe noises **my Tube arcing problem turned out to be that JJ 6ca7 was pretty fragile, and couldn’t handle the T2. I was sweating and checking everywhere to realize it was a ghost, until KG confirmed that JJ are junk. I stuck in Groove tubes EL34, and it got to this result.

Bob Mould - Workbook

Key lime pie

that definitely works, but the price is a bit goofy. probably what happens when you spend 10 years trying to make better parts only to make parts identical to the originals

Time for some impressions of this rare beast. The Icelandic distributor has a set on loan and they carved an entire afternoon out of the schedule for me to try it and do some comparisons. I showed up with the HE90 I built from spare parts, Aristaeus, Carbon amp and a port modded SR-007Mk2. Since they were using the built in dac on the HE-1, I just plugged both amps into as well to equalize the comparison. Over all, I like the build quality of the headphones. Imagine a HD800 built properly and you are pretty much there. The leather earpads are super nice and the headband has nice extension to even fit my large melon. I don't think they are super comfy though as they are fucking heavy (550gr) and all of the pressure is on the top of the head. The Stax 4070 is just about as heavy but far more comfy due to the suspended headband design. The earcups get a bit warm due to the internal amps but only about 5-7°C above ambient. The cable is also pretty nice and not microphonic at all but more on the amps etc. later. Amp itself...well it is just fucked up. I get that they were trying to cater to some nouveau-riche people who just want something expensive but the wank factor is off the charts. I also have serious doubts about what's hiding in that nice marble shell... As for the headphones them selves... well the drivers look pretty much identical to the HE90 units and the few pictures of them that exist, point to that. I wanted to rip off the earpads to check further but people get antsy with something this expensive... One worrying thing I noticed though is that both sides of the drivers have porous dust covers. They look identical to the woven nylon found on the HE90 and well...I would expect solid covers. Now for some actual impressions. As I said above the HE-1 dac was the source for all the amps. To that you have to turn off the headphones so no direct comparisons were possible but I know how both systems should sound so not a big problem there. The source feeding the HE-1 was a Macbook Pro running itunes but I bypassed that with my own FLAC files and player. There are some major changes compared to the older system, this one can do bass and isn't as horribly colored either but over all...I was not impressed and the system never made me really interested in the music. It doesn't engage like a good 007 system can, where I sometimes just sit in awe even after owning a set for all these years. Here, it just doesn't pull me in. This is clearly a midrange issue as there just isn't enough presence there. First off the major issues are the bass, treble and the soundstage. Let's start with the bass, it has this annoying hump to it sort of like the old Lambdas. I'm not sure if this is the mosfet driver (could be, the Cavalli crap boxes have similar issues) or the headphones but it is a clear coloration and once you notice it, just annoys the fuck out of me. Now on some tracks it wasn't as noticeable but always lurking in the background none the less. Next up is the treble...which is both subdued and bright at the same time. I know plenty of people complain the 007's lack sparkle and with the Mk1 this was mostly true but they could be bright if the source called for it. The HE-1 manages something different, the treble is just flat and boring but then it suddenly bites hard. Now I was listening at higher levels but still nothing super loud, only about 12 o'clock on the dial. This also wasn't like the upper midrange bite of the 009's, more lower treble fizz but the source material didn't call for this. I'm so used to listening to SR-X Mk3 Pro drivers now (which are pretty much the gold standard for treble) as they are in my DIY headphones and nope, nothing like this. I suspect the amp is a huge influence here too but no way to verify that... Last major issue, the soundstage. Many will know my stance on the old HE90 where it sounds like you are listening to some people playing in dense fog and you can't quite make out where they are. This time around it is much improved but the lack of pin point accuracy is still apparent. The soundstage is also a bit too far away for my liking and it just doesn't throw the same huge headspace the 007's can. This also affects the midrange and the whole "disconnected" feeling I got from the whole system. I once reached for my phone as I was just a bit bored listening to it. Over all I like that Sennheiser built this but they really should have spent more time on the electronics. I don't think there are any improvements to moving the amps to the cups over something like the Carbon where I can burn 50+W as heat and overcome the small capacitance in the cable. Next post will discuss the tech specs of the system but I'll end with another picture of it all... It was really dark in there and I suck at taking pictures... Now for some technical discussion. I found the specs in the back of the manual and it turns out the bias is 650VDC and the amps run at +780VDC. This makes this more than compatible with Stax so I see no issue with removing the internal amps and rewiring one of these for Stax use. I have been asked to that before but I'm really hesitant to mess with something this expensive. That said, moving to proper amps which are not just the HEV70 rehashed can only be an improvement. I've never found any mosfet device with sufficiently low Cob to work in this role so I truly don't get what Senn were thinking. Some other info, the entire amp only consumes 40W per the user manual which doesn't leave a lot for the actual amps. So we have 8 tubes running with heaters plus all the motors in there. HV supply for the tubes, another for the output stage and well...not a whole lot of power to spare here. Compare that to the BHSE, Carbon or even the T2. All of them use far more power and it is just for one goal, to power the headphones. I also played around with the amp and I could swear that the volume control feels like a RK27. No way to know but how it felt when moving to the extremes...it was just like a RK27. Now as a proper volume control aficionado... ... they all feel a bit different. TKD feels nothing like a P+G or a RK50... Until somebody opens one of these up, take it how you will. It is also clearly a volume pot and not a chip or some other setup.

This was back when i had power at my house....been 36+ hours without, and counting..... New Shpongle! Have to say, though, was a bit underwhelmed for the first few songs, a bit bass-heavy EDM for me. But they got more of that Psy-trance in later, so got better,

My Life with the Thrill Kill Kult – 13 Above the Night

I thought I would provide an update on the sound of my 2 SRX-Plus amps. I used new Penta Labs quad 12at7s that were balanced and matched in both builds. I used some existing NOS 12AT7s I had laying around and could not balance the amp correctly. With new balanced and matched Penta Labs, it was a breeze to get the amp dialed in. Then for one amp, I used new Tung Sol 6SN7GTBs, and in the other, NOS GTA Sylvanias. The Sylvanias sounded better out of the gate. cleaner and crisper sound. Tung Sols seemed a bit muddier. I have been primarily listening to the Tung Sol amp for the past week, and it appears that over time, the amp has become more clear and defined; less muddy. I am not sure I believe everything I read about break in periods for headphones, speakers, tubes, etc. Much of the break in talk is not supported by objective measurements so I am skeptical. However, it sure seems that something has changed in the Tung Sol amp over time. And I don't think it is just my ears because I have been using an HD650 Sennheiser as reference for comparison. Both driven from the same O2 DAC/AMP source, with line out of the O2 DAC going into both the O2 Amp (for HD650s) and the SRX-Plus (for SR-507s). Of course, the SRX/507 combo always won, but at first, the HD650s just seemed cleaner less muddy. There was and is a surprising amount of bass coming from the SRX/507 combo, but the bass seemed too muddy and was somewhat fatiguing. Now, that muddiness in the SRX/507 seems mostly gone. Still not perfect, but better. Not sure if this is a combination of the amp settling in, the Tung Sols breaking in, the Penta Labs breaking in, my final dialing in of the amp outputs (my offset was about 70V or so before I did all the tuning to get it to essentially 0V after warm up), or maybe my ears getting more used to the sound. But the SRX seems to sound a bit better every day. I have about 30 hours of listening time on it so far. I will report back when I cross 100 hours. I did notice that when I put the NOS Sylvania SN7s in my amp instead of the Tung Sols, it does sound noticeably cleaner and clearer. Perfect, really. No trace of muddiness at all. And that is without retuning the amp for these tubes. So perhaps there is something to be said for either the quality of those old tubes, or the fact that new tubes need an extended break in period? Why do I continue to use the Tung Sols, you ask? Well, because my son's ears are much better than mine, so he gets the good Sylvania tubes! For someone coming from Dynamics or even Stax driven by SRD-7, I would rate the sound as SRX-Plus/507 >>> SRD-7/507 >>>>>>>>>> O2Amp/HD650 So I would strongly recommend the SRX-Plus build. Just be aware of the importance of good tubes both in dialing in the amplifier and in quality of sounds. And if using new tubes, given them time to break in.

According to the DIYAUDIOSTORE site, that price comes with 2 matched pairs.

pizza

I don't, but could potentially start working on layout in a few weeks, given enough people want it and Kevin is okay with it. Do beware that even though the boards can be shrunk much smaller using SMD parts, the heatsinks obviously need to be the same size as before to dissipate the same amount of heat. I need to experiment more with forced convection to really get things small.

They're probably just using an old photograph.

Do you two ever change your t-shirts? You wore those when I visited a week ago Congrats to Steve on the move and Al on a new "neighbor".

Can Birgir interest you in a nice KGSSHV Carbon....?

Went to a race on the Chicago Cross Cup series today, Lots of fun.

That was not their retail price, that some morons are willing to pay a premium for those pieces of arguable shit doesn't justify a half cooked headphone should cost 4K new.

Was at Newquay, Corwall (UK) to watch Bloodhound SSC doing its first public runs. Just using the Eurofighter Typhoon jet engine to propel the 5 ton vehicle to >200mph in 8 seconds. It was bloody awesome. In no uncertain terms it was bloody awesome. Next year, using the the jet engine and one rocket there will be a straightforward land speed record attempt of around 800mph, and in 2019 the full >1000mph once they have put in a cluster of three rockets. This is a long video, but the first section is well worth watching, as is Andy Green's commentary on his supersonic record 20 years ago. The first hour and a quarter is about yesterday, and then 2h to 2h15 is about the supersonic runs 20 years ago.

Or you have more 12AT7 problems.

Looks like a great time. Can’t wait until I can join the travel team.

dbel84 once again puts foot in mouth with this gem "I can also tell you that he will not be publishing any of the production designs for DIY. This is not selfish or mean spirited but rather more of a support issue as the boards are 4 layer and very specifically designed to perform the way they do - anyone trying to lay out a 2 layer board will run into some challenges. I had this conversation with him a long time ago as designs were retired ( Liquid Fire ) , and know that his positioned would be unchanged. Laying out boards was a gift that Alex had, I have yet to see anyone so skilled , it was part of the artist in him." I think birgir will agree that alex's layouts are among the absolute WORST that we have ever seen. Specifically for the Liquid Fire, LL mk1, LLmk2 and LG, they are all 2 layer boards with 1 oz copper, super thin lands that wander all over the place, and solder pads that are way to small. The left channel does not match the right channel on the Liquid Glass. The liquid carbon is just a terrible layout. As the stax mafia did in the past publishing every single singlepower design (except for one, never could get a active cable driver) I assume its our job to now publish both schematics and diy boards for every single cavalli product