djk

1959 JBL vs Klipsch

The early Cornwall had the drivers soldered to the internal speaker wire, the later models did not. Even when new the later Cornwall had a problem with the image drifting. Soldering the wire to the drivers will fix this, but Bob Crites says a lot of people ruin the tweeter while doing this, and thanks me for the replacement diaphragm business he gets from these people. If the ESR is high on the original caps (over 0.5Ω), they will benefit from being replaced.

Two things damage speakers: Mechanical damage (from too much excursion). Too much average power. (notice that clipping is not one of those two things?) Compression raises average power, and thus burns out drivers. --------------------------------------------------------------------------------------- Clipping blows out drivers, not because of the clipping, but because of the increased average power in the program material during the time when the amplifier is not clipped.

I remember the FT101 tuner, it used a $20 Alps tuner can (like a car stereo).

The PD4V has no phase plug, and just looks like a big hill at 2.5Khz, rolling off above and below there.

Put up a link to your schematic.

Joined on 09-01-2000 Posts 1,891 Re: Using 4 ohm tap or 8 ohm tap "So are you saying that you can get better sound on the 4 ohm tap with Klipsch speakers and tube amps?" At low volumes a speaker always plays loudest on the 8 and 16 ohm taps. As you turn up the volume and 'thump' it a bit you will find the speaker sounds the best on the tap that closest matches its impedance, and plays the loudest too. Always try the 4 ohm tap. Leave it on whatever sounds the best. Hint: it sounds 'thin' when you turn it up if you have it hooked to too high of a tap.

" I used by router and dug our 1/8" to clearance for k55. " Klipsch did that on some of the pro versions of the LaScala.

Those early Nak receivers were built under license to Nelson Pass, a patented Stasis design.

They shut off the power to my room when I would play my 30W Sansu too loud (on my Altec A7's).

+1 on the Thorens.

Check for a dirty speaker relay contacts.

Measure the ESR, if it is over about 0.5Ω, replace.

http://www.ebay.com/itm/Klipsch-La-Scala-Factory-K-77-F-Tweeter-Horn-Diaphragm-Faceplate-Assembly-127126-/151254367672?hash=item2337767db8:g:jcMAAOxy3HJTI3ez The only one I have seen that is OK, the cheaper ones are junk.

" I have a question about my Carver M1.0T amps. I have used them in the mono bridged mode pushing some Infiniti Kappa 7's. " Do you drive your car into brick walls too? The M1.0 will run in mono into 4Ω for a very, very, very short period of time. It will rip your face off with a single stereo M1.0 driving a pair of RF7's. The M1.0 only has ONE output pair that must provide all the current to drive the load, all the other outputs are in series. That pair of outputs is only rated at 15A, and the gain drops like a rock above 8A or so. 8A is 5.6A RMS, or 32A^2 * 8Ω =256W/8Ω (in stereo).

In RF circuits the outer foil is connected to the lowest potential (side closest to ground).

Clean them up a bit, use Kiwi black dye on the raw wood. http://www.ebay.com/itm/Klipsch-La-Scala-/172529027470?hash=item282b88098e:g:AAgAAOSw2gxYoPYi http://www.ebay.com/itm/KLIPSCH-LA-SCALA-VINTAGE-SPEAKERS-LS-BR-SERIAL-24U458-24U456-/292051891549?hash=item43ffa6355d:g:JBgAAOSwdGFYwz76

" MCM drivers. Hope this is a hit a $31" When you measure the T/S parameters, you will find them way off (Qts much higher) They will probably require the box to be at least twice as big as you think.

Two 15's, 6 cu ft, 35hz.

Made after 1987, week 39.

" Pick up an MC 2105. " Capacitors Posted by djk (M) on May 9, 2009 at 06:26:50 In Reply to: DC output during startup posted by mikeg on May 7, 2009 at 14:52:35: The MINIMUM age of a MC2105 is 30 years old. The first thing I would do is replace all the electrolytic capacitors. ----------------------------------------------------------------------- I own a MC2100 and two MC2120s. Caps wear out. Even when not in use. This list is for the MC2100, electrically it is the same as the MC2105, just without the meters. Even though your old amp is still working, you have no idea how much of the music you are missing. The parts are inexpensive. Digi-Key is good, Mouser has no minimum order. Posted by djk (M) on July 11, 2004 at 04:29:36 In Reply to: Re: MC2105 @ $ 100 even @ 20 yrs old is a best buy for me. posted by julian4@telkomsa.net on July 06, 2004 at 14:58:04: The sound would benefit greatly from replacing a few dried out electrolytics, and adding a few film types here and there. C301, 302 is the main input coupling cap. It is a Mylar type so it is likely to be OK, upgrading it to a Polypropylene type with give a smoother sound to the high end (0.47µF). C307, 308 are emitter bypass caps, 100µF 15V. Replace with same type and add a 0.1µF film bypass. C309, 310 are the output coupling caps for the pre-driver section, 10µF 25V. While a film type would be better, size is a problem. The DC bias across this cap also helps out with its being an electrolytic. Replace with same type and add a 0.1µF film bypass. C303, 304 are the DC power supply caps for the front end, 470µF at 25V. Replace with same type and add a 0.1µF film bypass. C1, 2 are the feedback loop caps, 330µF at 3V. The signal goes through these so replacing these with new ones and adding a 0.1µF film bypass really opens up the sound. Go with as high a voltage as what space permits. C11, 12 are the DC supply caps for the voltage gain stage, 150µF at 50V. Replace with same type and add a 0.1µF film bypass. C201, 202 are the main filter caps, 39,000µF at 40V. These may be quite expensive new, although I have seen them surplus for very low prices. I would use then unless signs of leakage or amplifier hum are there. Add a 47µF at 50V cap in parallel with each. C203 is a multi-section cap that will be very hard to find a fresh date code. New caps are small enough that they may be wired to the terminals of the old one, leaving the old one in place. This cap is important as it provides the current for the diff pairs and the VAS. The sections go 80/80/150/50µF with the voltages being 200/200/150/150V. If you measure the voltages 100/95/90/80V are typical, so 200V caps are not really needed, but 100V is not enough.

"Really... was material coming out the entire time?" No, I quit when it seems clean, re-assemble, then listen. Sometimes there is debris under the top plate (especially if someone used compressed air and blew it back away from the gap), and it works its way back to the gap. "I made a couple passes, didn't see any debris, and reassembled." That's what I do too.

" what the difference be on swapping an 8ohm one " You would need to change the crossover parts for the 8Ω driver, and adjust the levels for the mids and HF (including some part value changes). http://www.usspeaker.com/KappaPro-15LFC-1.htm Will need an extra gasket and a minor cabinet mod.

The Hughes (Peavey) is a conical, with a Quadratic throat (and sound quite good, odd 1.6" throat though).

I've had to spent hours cleaning just one driver (before they quit buzzing).