Milosz

Wonder if the drivers are bespoke or just some other company's dynamic drivers put in nice wood earcups?

Nice!

Hahaa yeah. I tend to get the stuff all over my fingers. OK, so the regular white stuff is OK, no need to try to find some exotic high-voltage rated stuff compounded of finely divided unobtainium oxide.

Quick question: what type of silicone heat sink compound are y'all using with the alumina TO-220 insulators? Is the regular white gunk OK to use, or is there some special stuff to use instead at these voltages?

Wow, good stuff!!! WOW!

The advantage to the owner of wooden headphones is that they can look nice. In some instances REALLY REALLY nice. The advantage to the builder is that shaping a headphone cup or driver support ring out of wood doesn't require the tooling that carving one out of aluminum would, and doesn't require the really expensive dies that making them from plastic or die-cast alloy requires. Look at Audeze- to tool up for plastic molding dies for their 'phones would probably have been so costly they wouldn't have been do-able, but using wood worked out well for them. Wood also has some self-damping qualities, it tends not to ring. That's a good thing. Many plastics can be found that also damp nicely. Metal can be damped depending on what you glue or bolt to it. So, while wood is not unique in being OK in terms of damping, it is among the materials that can suitable for earcup fabrication because it generally won't ring like a bell the way some materials might. For example, a thin steel stamping might not be the best earcup... or a glass dome...ring like bells, they would. By the way I am introducing to the market a new WOODEN CABLE for the HD800......

FYI This knob was fabricated for me by Master Lapidary DONALD SLATER at NATURE'S GALLERY http://www.natures-gallery.com/ Total price was $50.00 INCLUDING THE MATERIAL! (Tiger's Eye) And although it's hard to tell from the pictures, the surface is glass smooth, the natural flaws in the stone do not "come through" as cracks on the surface. Tiger's Eye is basically asbestos fibers embedded in quartz, colored by iron and sulfur traces; there are inclusions of other minerals in the stone as well, some pyrite etc. So what looks like a "crack" is basically a vein of transparent quartz. It adds to the fire, and although in the photo it looks like a crack, "in person" it looks more like a transparent plane cutting the material and is completely smooth on the surface. The lapidary put a nice, sharp bevel along the top edge, which you can see. Excellent craftsmanship. This will be mounted on a polished copper front panel, with a cylindrical recess cut into it..... I am thinking the front panel will be a 1/4 inch thick copper "slab"..... Here's a rendering of the design, the copper comes out as solid tan color but the finished item will be more mirror-like. Heat sinks along the sides, power supply underneath, separate chassis. The wood is figured bubinga, which in person has pink colors to it that compliment the polished copper. In this rendering the knob is black. Obviously it will be the tigers-eye knob when built..... completion may be around September. I have all the parts and materials but my workbench has two other electronic projects ahead of this one. The final design will vary somewhat. For example, the wood front will probably be the same width as the heatsinks instead of allowing the heatsink to protrude.

Blind concentric hole drilled in back of knob; Stub shaft epoxied into hole. Stub shaft passes through panel bushing behind front panel, and connects to the attenuator's shaft via a "coupling" - see photo below, sold at http://www.octave-electronics.com/Parts/hardware.shtml

Here is the second of the tigers-eye knobs. This one is larger diameter. The photo doesn't really do it justice, there's a lot of fire (chatoyance) in the stone as you move it which doesn't show up in a still photo.

Gilmore's Corollary of Murphy's Law states that the counterfeit MOSFET from eBay which saved $5 will take $350 of hard-to-find parts with it.

http://www.americanelements.com/osmd.html Hahahahaha "American Elements specializes in producing high purity Osmium discs......Our standard disc sizes range from 1" to 8" in diameter and from 2mm to 1/2" thick. " 3 inch Osmium disc 1/2" thick = knob Osmium is good if you like a dense knob...make a good flywheel for a tuner. Pricey....

Damascus steel of meteoric origin, I hope!

I think it's hilarious that there's a SEPARATE THREAD - with 9 pages of posts, yet!- for T2 knob making. If you tried to explain that to a non-audio 'outsider' I have a feeling they'd find it hard to understand.... Actually these knobs don't need to go on a T2. You could put them on your Beta 22, or your Philco TV for that matter..... The lapidary (Hiddenite Gems) where I had the tigers' eye knob made was fascinated by the idea of a fancy decorative knob for fancy audio gear. They "got" it at once, in fact the actual worker (lapidary tech? lapidarian? Lapidarist? ) who did the work is making a knob for some vintage radio she has. She dug the idea. By the way, price estimates for the work that I got ranged from $850 to $35. The $35 included using their own chink of Tigers'e eye.... I chose the next highest (second cheapest) quote for the knob made using my chunk of tigers' eye- the one in the pictures- and ALSO gave the low-price guy the $35 (plus $8 shipping) make me a knob, so I will have two to choose from.

Yes, with the right casework, a lapis knob would be very nice. Maybe with a nice bright aluminum case. Or, with a very pale wood front escutcheon. It isn't JUST about the sound, the look and feel of the materials / workmanship bring pleasure too.

Thanks for all of the wonderful compliments. The surface of the knob is actually smoother / glossier than it looks in the picture, and of course the material exhibits the characteristic 'chatoyance' of tigers-eye - the shifting reflection effect. I got a chunk of tigers-eye on eBay for $8 and found a lapidary that fabricated the knob for me, the price for the work was reasonable. They did a WONDERFUL job, they are Hiddenite Gems, http://hiddenitegems.com/ [email protected] if anyone else wants a semiprecious knob. ('Semiprecious knob' - that just doesn't sound right .) There are other nice minerals - PERISTERITE, LABRADORITE, AGATE, MOONSTONE of various types, and even FIRE OPAL.....

Now have a finished knob for my (under construction) DIY-T2 Material: tigers-eye

I don't see the advantage to this scheme. Any CD player will use the Reed-Solomon error correction that's built into the Redbook standard for most errors, and this mathematically produces exactly the correct bits that are lost due to the error. This happens on-the-fly; all CD players have some kind of buffer where data is placed for some short period of time as the disc is read and the algorithm is run. More serious data read errors that cannot be overcome by error correction have some cut-and-paste replacement type thing that happens, basically if a block of data is lost that was too large to be recovered by the Reed-Solomon code, then the last good data is plugged in to the hole- this is "ERROR CONCEALMENT." And if an even larger block of data is missing, the player will mute. Beyond that, the disc is rejected. Obviously this "repeat" method of covering up errors is not a good thing to have going on with any regularity, it can be seen as a form of distortion- a fairly serious one. HOWEVER, in my experience, a CD in decent condition never reaches this point. I had an NAD CD player that had an indicator LED that showed when errors uncorrectable by Reed-Solomon recovery occurred- and unless a CD was in bad shape, the LED never lit. Just to be clear, the Redbook standard for a CD provides that the amount of bits burned to the disc is essentially DOUBLED, the extra data being the Reed-Solomon checksum bits. So between the audio data and the additional error correction checksums, there is enough data to recreate the missing bytes with ZERO errors in the output, as long as the bit-error-rate is below some reasonable level. What's stored on the CD is just a series of numbers, and using math you can solve for missing pieces. See http://en.wikipedia....3Solomon_coding Essentially it works like this: Let's say we have three bytes from the data stream, in sequence as they are recorded on the CD 8456 8448 8439 For our error correction code, we will use the DIFFERENCE between each successive sample - thus: DATA | Error Correction Code (calculated at the time the audio recording is being prepared to manufacture the CD) 8456 (8448 - 8456 =) -8 8448 (8439 - 8448=) -9 8439 So, we have three data samples from digitized audio, and two code numbers which are stored along with the audio data on the disk. Let's assume the middle audio sample, 8448, is lost- can't be read from the CD. DATA | Error Correction Code (calculated at the time the audio recording is being prepared to manufacture the CD) 8456 (8448 - 8456 =) -8 -missing!- (8439 - 8448=) -9 8439 Well from the remaining known samples and the error correction code we do the following math EXISTING SAMPLE (8439) + ERROR CORRECTION CODE (-9) = MISSING DATA = 8448 [This is an example only, a simplified version of what goes on with CD error correction] So, you can see that the Solomon-Reed code result is ZERO data loss when the disc is being read, unless the number of errors is too great for the error correction setup. These minor read errors result in NO LOSS of audio, as the error correction scheme is mathematically perfect. So, since the existing error correction built into a CD provides perfect recreation of the data originally recorded onto the CD unless the error rate climbs too high, and in real life the error rate never gets that high unless the CD is defective, has been used by someone as a coaster for his beer mug, or is otherwise generally pretty scuffed up, I don't really see the value of going through all of this extra trouble and expense. And, if you are really concerned about playing back a CD with zero errors, you can always use your computer to rip the CD to Wav or other lossless format and check the resulting rip against the AccurateRip database. (Many CD-ripping programs will do this for you) If you rip a CD and the AccurateRip check says it error-free, then you have an absolutely, bit-for-bit identical, error free copy of the CD on your PC, which is EXACTLY the same data as released by the folks who made the CD. This is even MORE likely to be 100% perfectly bit-accurate than the "double read" idea in this Halo player, and you can do it with your existing PC and DAC, without spending the $5000 for the player. See http://www.accuraterip.com/ Having said all this, I do want to go on to say that the Parasound Halo gear is generally really fine equipment, and in addition to this redundant read method for playback, I'm sure this player would have a very well implemented DAC and very clean sounding analog sections, good power supplies, beefy construction and so on.

Could you cut that stone on a CNC mill? Wouldn't even a silicon carbide cutter get dull about immediately? I guess diamond tools could be used, at low speed. Yeah, tigers eye, the fibers inside are asbestos.... don't want that flying around. Actually even ordinary silica-type rock dust is bad. But... I wonder if someone with lapidary skills and gear could turn this 2.5 inch lump of rock into a short, wide cylinder- i.e., a KNOB. Maybe with a domed top, sort of quasi- cabochon...? Or maybe a flat "bar" type knob...

Tiger's eye? http://www.ebay.com/...e#ht_1700wt_879 Hone your lapidary skills and make a knob from this.....

Some of these burls might make cool knobs or panels http://www.hearnehardwoods.com/hardwoods/exotic_hardwoods/exotic_wood/australian_goldfield_burl_lumber/australian_goldfield_burl_wood.html

Tungsten. Osmium.

I think a metal knob with an embedded peltier would be a fun idea, you could have a control on your amp to set the knob's temperature to your liking- cold or warm....

You are all entitled to your wrong opinions.

I find this further comment quite interesting. I have an LCD2 R1, and SR-007 mk II; I am now less interested in trying to come up with $4,700 for an SR-009 - I think I will "stop" with the SR-007 for now. I am not a bass freak, but it is one of the aspects of music I enjoy most - the impact, the texture..... for example I absolutely LOVE the bass from my Quad ESL-57's (within their limits of course)