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MikeS

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Posts posted by MikeS

  3. Posted · Edited by MikeS

    I had a pair of Kicker C12's way back in the late eighties. After a year or better of hard use, I started to hear slight buzzing noises at low volumes.

    The dustcaps were coming loose. I re-glued them, and the buzzing stopped.

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  4. Posted · Edited by MikeS

    You'll play hell trying to find american made capacitors in any of those amplifiers pictured.

    Even when it comes to restoring a old hi-fi tube amp, most the replacement electrolytic capacitors are sourced and made overseas.

    Even the modern "Sprague Atoms" are made either in China or Japan.

    Except the CE Manufacturing aluminum multisectional electrolytic capacitors......I think they are made in the US, in Califiornia or some such.

    Most the high quality boutique Electrolytic capacitors are made in Japan. Such as the Nichicon Muse series, Elna Cerafines, Rubycon Black Gates........

    I'm sure there is quality made American electrolytic capacitors out there, but I really doubt they will be in common consumer grade car electronics.

    I also wouldn't doubt all those amplifiers pictured are made in the same South Korean plant. The plant probably does quality control, and the dealer who pawns them off in the states probably does testing and more quality assurance before they are sold.

    And with a whole pallet of amps, I'm sure they have to go through, test, and ween out some of the bunk ones.

    :ughdunno:

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  6. Posted · Edited by MikeS

    He had lots of test equipment. That would be something useful for me.

    As far as I know, the Citation II is still sitting on top of his piano in the shop. That thing is a beast of an amp. Lots of Iron in that. He had all oft he original literature with it. He showed it all to me. He even had all the newsletters that got sent to citation owners. Very cool stuff.

    I want some tube amps to run my Dahlquists. maybe 60 watts per side. Either a set of monoblocks or a 2 channel. I have been on the lookout for a while but everything is out of my range(I'm still broke)

    Well, the Citation II is 60 watts a side. The "Deuce" is a classic, a keeper, and well worth the investment.

    They don't depreciate......

    http://www.bassboy.com.au/getreel/ebay/cla...ps/hk/specs.htm

    I'd try to follow up on it, or at least see if it's still up for grabs, or up for grabs at all. Even if you can't afford it.....

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  7. Posted

    Nice!

    Unfortunately, the guy who owned the local Hi-Fi passed away a couple weeks ago. I may end up picking up a few things before the fmaily closes shop.

    He has some nice project pieces, so I might be starting a rebuild soon!

    I wish I could get his HK Citation 2 he had sitting around. That thing was a beast of an amplifier.

    That sucks. Sorry to hear that Todd. Those old timers pass on, and another little bit of the old school knowledge disappears along with it.

    Yeah, I'd be trying to glom on to whatever you can afford/get your hands on.

    Along with projects, maybe see what he has in the way of test gear. Old school volt ohm meters, VTVM's, tube testers and tubes are things to snag.

    What happened to the Harmon Kardon Citation II amplifier? Did it pretty much vanish right when he passed away? That's a well coveted amplifier, and worth a few bucks as well.

    I hooked the Altec 345A amplifier up to my LaScalas just about a hour ago. Plenty of power, and bass is strong.

    It has new tubes except for the 5U4 rectifiers, and brand new parts. So it will take some time for the amp to settle-in. It still sounds rather good, however. Just a wee bit bright/weedy......and I'm pretty sure it's the new parts and EL-34's. Time will tell I suppose....

    I listened to it about 20-30 minutes just to hear it. Now it's back to the bench for testing/checking/measuring on the scope.

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  9. Posted

    Don't listin to all of them. Plug it up to the wall. The sine wave is good for it, it will make it happy!

    This type of crap is what helps people ruin their equipment. If you don't have something informative to offer, do not post anything.

    This is counter-productive and a stupid thing nonetheless..... But a buddy of mine Johnny back in the late '80's-early '90's was back east or in Texas or somewhere at a Soundstream dealer. And one of the sales pitches/gimmicks was to plug a Soundstream driver directly into a 120 volt AC wall socket.

    I remember my friend bragging about it, buzzing away at 60Hz without burning up.

    I have no idea how long long the test was performed, (probably not very long) or if there was some sort of device or something to limit current to pull off the trick.

    I suppose back then I would have been impressed as well, watching a subwoofer plugged into the wall......you know.....WOW! Wotta tough subwoofer.....

    Nowdays, I dunno........Well, that's cool.... now let's try it at 240 VAC, and work our way up to 480 VAC....

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  11. Posted

    Ive been looking at these subs hard and on there site all of there subs,12-18 have 2000rms.What is there peak?

    What standard?

    I know they are at least 10,000 peak at 125ms, 20,000 peak at 62.5ms....

    Do you have idea if those driver peaks were determined in the proper specced enclosure, or measured free-air/open-baffle?

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  19. Posted

    I dunno if it matters where you set the input gain on the amp. I would think you could still clip the amp regardless if the gain pot is set low or high.

    I think it just boils down to a simple act of volume control moderation.

    If the woofers are going clickety-clack, the mid and top end sounds all grainy and compressed with a touch a broken glass thrown in, and the tweeters are going squick-squack........it may be time to turn it down......

    I dunno........

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  20. Posted

    They'll work with just about any 2-way crossover you get, they just won't work well.

    Every single different component set should have a crossover optimized for its particuar drivers. There is no such thing as a "universal" passive crossover, you'll see them advertised sometimes that way, but it is marketing.

    Do you still have the old ones? If you get me a close up picture of the guts from a few angles I can give you a schematic and help you buy PC boards and all the parts to build yourself a new set, a set that would probably sound much better...

    Would probably cost you around $40

    that is what i was thinking... the cross overs were made for the speakers it was with.. while i was shopping i seen some guts close to mine and some waaaay offf.......

    i sure will take some pics and post them.. one of them in still in tact so just the leads are broken!

    ill take pics this afternoon thanks!

    There ya go, just reverse engineer the crossovers. The values and voltages should be be indicated on the capacitors and resistors.

    If there is a inductor or two, it may be a little more difficult if the value isn't listed on the part. Unless you have a way to measure inductance. You can still probably use the same inductor/inductors if need be.

    You could source the parts from PE. You can get into some nice metalized polypropelene capacitors for a good price, or even film and foil if you want to get particular.

    There is the issue of microphonics with regard to passive crossovers when the mounted inside of a speaker box, when ran at high levels. (vibration from the woofer)

    I've never had much issue with this in home applications that I can tell, but the listening levels are lower.

    Of course you have the passive xovers externally mounted being a car component speaker set, probably close to the subwoofers?

    If the SPL from the subwoofers is enough to crack and break the PCB boards to the passive xovers, then I think maybe the microphonic issue may apply here......

    So when or if you build the new networks, you may want to take that into consideration and maybe damp the crossover networks real good, or maybe even pot them. Build 'em so they are impervious to vibration, and won't break.

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  22. Posted

    I dunno, there isn't anything "mythical" or special about BTLs... They don't model wierd, in fact when I ran the T/S parameters, they say big ported box... Go figure.. And they do great in the 40-50Hz region... They are efficient, very efficient and look great for getting loud....

    In fact, it models very similar to the Aura NRT-18, which I have a TON of experience with.... I know how to make that thing get loud, I am sure the BTL would be just about the same...

    The BTL doesn't seem much unlike a pro-sound woofer. Calls for a big ported box, high efficiency, works best in the 40-50Hz range......Hell, I dunno....

    95Honda knows how to make things get loud, trust me on that one.

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  24. Posted

    Like Manbeer says, you can make your own. It's just basically a line level lowpass filter. (Or is it highpass? I always mix the two up.....)

    Which I think composes of a cap and resistor, in a basic first order network. (6db) I'm sure they can be configured in higher orders as well. The way the parts are configured determines whether it's high or low pass.

    Google search high and low pass line level passive filters.

    It's line level, usually in millivolts, so you can use smaller low wattage/voltage parts. The insertion losses are a lot less than a passive speaker level network, if at all I guess.

    I'm not sure if this is the proper formula for this application or not. But you can use values of R and C to determine frequency, or determine frequency and noodle in values of R and C to match the frequency value. This would give values of R and C for a simple 6 db first order network with a known break point frequency.

    1/2X3.14XRXC=F

    I used the value for C as 0.1 uF for the sake of math. 6.28X0.1x50000=31400 31400/1=0.000031847.

    The capacitance is noted in microfarad, (which is a millionth of a farad or some sh*t) so you have to move the decimal point over to the right six digits. So 31.847Hz, round it off to 32Hz.....

    A 80K R will give a break point frequency, ( with 0.1 uF C) at 19.9Hz....20Hz...

    Whether this formula evens relates to this application is beyond me, so take it with a grain of salt.

    But you could build one or two for under ten bucks I would think.....

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  25. Posted

    Subs just don't last

    I'll disagree with that, but I have to go now so it'll wait until later :D:P

    Edit: As long as the surrounds stay away from lots of direct UV, you'd be amazed at how long speakers can last and still be very playable condition. I have a friend that has a pair of Altec cabinets with 2 15" midbasses, they were made in the early '50s...other than one hole in a surround due to a mouse that was living in one of the cabinets, they all worked :)

    I've got a pair of Altec 415A biflex drivers, probably made from the mid to late 50's. They sound pretty damn good.

    They are still rather nice, with one having slight bumps in the dustcap from the original installer I would guess.

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