luvdunhill

Too bad I have the family with me, or this would be fun to look at and document, as I'll be in the area for the last two weeks in July. Anything in the area that I could sidetrack the family into doing without me?

Al: If I can do anything, just let me know. You're definitely in a hands of a very capable crowd around here!

x2 what Nate said. If you cannot go wild on the ventilation (including a vented bottom, IMHO), consider running the power supply rails lower and/or a lower bias point, as that will help with the heat.

just dropped it onto my Mouser order Let me know where I should send it!

Manuel: Let me see what I can do

I was sorta curious what these will start to go for. What's your opinion?

This is pretty common with most modded gear. The number of permutations isn't quite as many as Tony suggests, but there are 6 versions that I know of that really fall into two major categories.

nope, a bit larger than Justin's and are custom milled so that rails won't be necessary, as they are integrated into the heat sinks themselves. They are the largest profile Conrad makes. yeah, I'm hoping the phase change compound will make them easier to separate, but more on that later, as I'm still playing with it

oh ok. The cloth was clean as a whistle with water and a plain dry cloth. It wasn't until I added the oil that the black started come off.. and it was pitch black. Do you think there is a fixed amount of tiny particles on the heat sink, or it would keep rubbing off black as long as I tried to rub down the heat sink with oil?

Heat sinks and brackets are ready after using 600 grit sand paper, if I apply a bit of oil and rub the surfaces I end up with a black rag (um... okay, anyways) I'm not sure why this is, or what would be black, besides perhaps the sandpaper? Who knows.... Then, I mated them together with oil and couldn't get them apart... wish I had a vise or something... I ended up putting a small gouge in the heat sink when I finally got them apart by putting a lot of force on the assembly by using the angle as a cantilever of sorts... Looked through all my power resistors can don't have anything low enough (HV junkie), without paralleling 50 or so resistors together... so I'll have to head up to Frys, as I sorta want to test the sigma22 at load before doing much else. Hopefully this number of holes to secure the bracket to the heat sink will put me as the secure leader in team overkill, with digger945 in second place with plans of a measly "2 maybe 3 #6 screws"

are they like under your bed? you're going to have the most gear per square inch of living area I've ever seen!

Let's see.. 20K in the middle and 10K on the sides. I think that's right :/ I use two types of solder. Johnson IA-423 ternary eutectic (4.7% silver, 217C melting temperature) solder with various fluxes and WBT 8020 (4% silver, 180C melting point). The Johnson is much "slower" solder, making it ideal for certain types of uses, where the WBT is "faster".. I think you're probably seeing some of both on this board, heh. The Johnson is harder for me to get a hold of, but now it seems that PcX sells it with a different flux than I'm using now. You can buy direct from them in 1 lb spools and get just about any diameter / flux combination. I think it runs around $25 / lb from them direct, but I bought 3 lbs from them 2 years ago, so it might have gone up, who knows. Nice stuff. You can make it flow faster by adding extra flux, and I do this quite often, as you can see from the top of the boards there... I really want to look into getting a more aggressive flux cleaner, as on larger boards alcohol + air can doesn't work so well, but haven't gotten around to looking at the Johnson site to see what they recommend.

try woo*********** edit: fail

ok Jacob, everything fits. No need to move the JFETs, they are perfect. Still need to double check the orientation of the TO-92 parts, but it will have to wait until tonite, unless someone else can look. The jumpering for the regs is a bit annoying (pin 1 to 3 on one and pin 1 and 2 on the other), and given how slick the feedback jumper is, could a similar SMD jumper be added to the bottom of the board for the regulators?

Gotta head out, and will be busy until tomorrow night Maybe I can get another set of eyes to double check the transistors? I'm most worried about the orientation of the 2SC3381/2SA1349 and JFET "singles". I double checked it, but you never know. From top to bottom, left to right I have: JJJJ KKKK (not populated yet) ACC CAC ACA AAC AC CC AA AC AA JJ KK CC ... and pics to show orientation of the "duals"... zoom all the way when you view the pic, as the light made things hard to capture, and seems to make it look like there are some flaws in the dual assembly, which are pretty much smooth when looked at straight on... oh well, just a bit self conscious I guess Tomorrow I need to jumper the regs, jumper the feedback and install the MOSFETs. Then have to bolt my sigma22 to the heat sink and get things ready to flip the switch. I'll probably load test the sigma22 first, assuming I can find enough power resistors around here.

nope, never heard anything on Andromeda, that seems to be the other sale label? Last thing bought includes the following from Amazon: # 1 of: Windows Debugging: Practical Foundations Sold by: Amazon.com, LLC # 1 of: The Unofficial Guide to California with Kids (Unofficial Guides) Sold by: Amazon.com, LLC ... and a Squeezebox Classic from a member here!

cool, I like Pentatone. Any good deals?

yup, air

meh, but can it hit 1 Hz at 3 miles away like the one I posted? http://www.rotarywoofer.com/KING_IS59_Summary.pdf ... that U-Haul has some serious bump.

heh, nice one Those are the only parts I'd want to salvage out of Mikhail's amps. I have some of the older Vanderveen (sp?) design stuff, and they are quite excellent.

Not for these frequencies. 1W 1m is the standard for SPL. There simply isn't a standard for measuring Xmax, see my article above. SPL also accounts for Sd, so you can compare different diameter drivers directly. I've measured this many, many times. Hell, microphone calibration doesn't even come into play at this sort of measurement. I'll give it a rest.

because, it's a rather bogus parameter. The resulting SPL would be more appropriate comparison in my opinion.

meh, go with this: Eminent Technology: home

Xmax is a crock. I mean, what distortion to you define? I could define Xmax = Xphysical, why not.. I'd have a ton of distortion, but hey. If you think everyone uses a 10% number, you'd be wrong... It's just like Watts... without clarification, it's rather meaningless. edit: just found this link, good read: http://www.aespeakers.eu/knowledge-base/the-deal-with-xmax.html

nope. What about difference between underhung and overhung voice coils? Different topology means you cannot compare the numbers directly.