Nachmu DIY Blog

Apparently, Nichicon makes these boutique lines of capacitors, which I found out when I couldn't find 50V Panasonic FCs at 10,000uF anywhere. Nichicons are definitely more expensive, but not killer expensive, like Black Gate.

Besides, I'm not sure I can hear the differences among capacitors, yet. Well, I'm about to find out.

At any rate, I had some trouble installing them, surprised as I was that there is more than one kind of lead for capacitors. Imagine that! More than one kind of lead!

Aren't they beautiful, though? The looks are certainly worth the extra dough. These are the Nichicon KG Gold Tune series, 50 volts of pure 10,000uF goodness. I'm using them in this modified snubber setup of the the BrianGT LM3875 chipamp kit:

Click here to see my snubbered setup with the Nichicons installed.

This blog post anticipates a future, longer post. I must say, in the meantime, that the woodworking community should be noted for a high standard in communication skills. As far as any serious woodworker goes, professional or hobbyist, I've found that each of them can communicate in writing and in speech far better than the average man.

I wonder what that says about the craft?

MJK has released the new Mathcad worksheets, with more to come. I'm very excited about this, and as soon as I get about a million other things done, I'm going to build the next installment of the Caterpillars.

Let us exult in the power of Stanley #8
For he has conquered the mighty oaks.

Click here to exult in Stanley No. 8

Over at the DIYspeakers forum, there is a battle currently raging over whether an OB subwoofer can actually carry the low frequencies.

I'm inclined--under evidentiary review--to think they can go low, but only at certain SPLs. I also think that the key is size. An OB subwoofer has to be BIG. Gargantuan.

Fortunately, I have the space. And I have the wood. And I have a couple of chipamps lying around that need a home (i.e., a transformer and some big caps). And I have a couple of less-than-ideal 12" drivers with which to build a prototype (qts<.6).

I hereby bet that, in a sizeable room (10x20 ft or 1400 cu.ft.) under medium SPL requirements (I have little kids), my OB subs do the job down to 20Hz.

"Aw, crap!" I said to myself when I finished a day of researching building my own home theater speakers.

Here are some impenetrable mysteries:

1) The standard crossover frequency. By my account, the subwoofer covers really low frequencies, not just "sub" woofer frequencies. Thus, I have decided to build stereo subs to cover most of the low frequencies, and let the stupid mono low go without for awhile. Or maybe I can slap together something to add that LFE rumble. I don't think I'm going to kill myself to get 0-20Hz thunderclaps when my mains are going to be able to cover 20-120Hz without any troubles.

My only question is whether DTS encoding (or any multi-channel encoding) sends certain signals exclusively to the mono sub or if that .1 channel simply augments and supports 0-120Hz information.

2) Do I really need a center channel? Can't I do a phantom center? This is basically the same question as above.

I just knew we had affinities. I was reading through this thread from several years ago about what kinds of woods would be good [mmm...all sorts of poetic devices there...] for a speaker enclosure because I want to build a pair out of walnut, and this thread started a flame war, which can be summarized for 33 posts as "unprocessed wood is pretty much stupid" for this reason or another.

Some rather dismissive individuals made some pretty bold statements which didn't jibe with my immediate experience, namely that some unprocessed hardwood speakers sound good. Even worse than that, the thought was going through my head that unprocessed hardwood enclosures sound good because they introduce their own resonances. For a while there, I thought I had committed some awful heresy, then Nelson Pass chirped in here, in post #34:

I can't resist adding my two cents.

MDF is for the same lazy guys who think that speaker cones are pistons, and enclosures should be dead.

OK for those who like dead music, but I often listen to old speakers, and I can say that dead enclosures and inefficient speakers look (and are) easy to design, but they have yet to match really well designed live enclosures and sensitive drivers. Hard work and good taste still win the day.

Just because you can understand the numbers and plug them into currently available equations doesn't mean they're better -the sound is what counts, and the most critical listeners are the biggest iconoclasts of the "modern approach"; that "left turn" that consumer audio made in the 60's.

Give me an old pre-Dolby Ampex tape on a tube amp on a nice set of Tannoys in a live enclosure. You can have the THX in particle board.

Yes, I like how this fellow thinks! I wonder if he's a successful person of one business venture or another...

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Martin J. King, the proprietor of the great mathcad worksheets for transmission-line enclosures says that he is "trying for March," in pursuit of completion of some new worksheets.

I can't wait!

Audiophiles, the joke goes, are those who can hear what is not there.

I like that. I wish I were an audiophile.

...are those which cannot be heard.

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