Got my new diaphragms and caps in

[whtboy]

My order from Bob Crites came in today. New tweeter diaphragms and his B network cap upgrade kit which consists of polypropylene film caps, mounting brackets and a generous bag of spades and female connectors that fit over blade connections.

I normally enjoy DIY work, but I did not enjoy performing the upgrade at all, mostly due to the fact that I don't have a great work space, my lighting was poor and I wasn't able to find the pictorial guide I originally saw showing in detail how to replace the diaphragm. But I winged it, it wasn't terribly complicated and both channels sound pretty good, so I'm guessing I did it right. I will say the voice coil on a K77 diaphragm is very fragile, the magnet assembly is very heavy and there doesn't appear to be a great deal of difference from the operator's perspective between gently sliding the coil into the magnet and smashing the coil to hell when you put it all back together. I couldn't really see it going in without holding everything at an angle that makes the diaphragm want to move around in the process.

Bob charges a really fair price so put the diaphragms in for you, so if you're not curious and interested how to do it, I'd say it's worth it to let Bob do it. I have no patience whatsoever though, and I wasn't willing to have no tweeters at all for however long it would take UPS to ship the parts back and forth.

So, how does it sound? Overall I'd say I'm pretty happy. I've listened to a handful of CDs so far - The Wall, Joss Stone (Soul Sessions), Eric Clapton Unplugged and a handful of MP3s.

The imaging was very good on The Wall and Soul Sessions. Not like a pair of nicely setup Martin Logans, but pretty good considering the limited placement options I have in my living room. The imaging on Eric Clapton's Unplugged sucked something awful and I can only guess that it might be the recording itself. I'm listening to a 160 kbps MP3-encoded track of Coldplay's "Green Eyes" and the image on that is far better than the Clapton disc.

I still have a number of reservations about my system in general, but overall I am much happier with my Cornwalls now, and I am very pleased with the upgrade. I highly recommend Bob Crites' cap kit and diaphragms. His prices are extremely fair and it's been a pleasure dealing with him.

THANKS BOB!!!

Now for some pictures...

[whtboy]

My left tweeter was out when I bought the speakers. The left diaphragm had no writing on it, but the right diaphragm (which still worked) had "4-9-89" written on it in black ink. The driver assembly looked the same on the outside but the paper that sits between the diaphragm and the magnet was different. The paper in the dead tweeter was cut to fit perfectly in the plastic assembly and hold the diaphragm in place.

The paper behind the 4/89 diaphragm was just a ring of paperboard that I had to carefully center on the dome. Not confidence inspiring.

The 4/89 (working) diaphragm measured right at 6 ohms. The dead diaphragm tested as an open circuit.

If I ever have to replace K77 diaphragms in the future, I will still probably do it myself, but I will make better preparations for quality lighting, delicate tools, one of those magnifying lamps, etc.

The 4/89 diaphragm:

[whtboy]

New diaphragms from Bob (they both looked like this and had the same date on them - 11/05)

[whtboy]

Here's a pic of one of my Cornwalls open prior to the upgrade, just in case there are any people (like me 3 hours ago) who are thinking about doing this and are curious what a corny looks like inside

[whtboy]

Here's a pic of my first crossover, half-done. There are two caps on a Cornwall B network. The cap on the left is from Bob. The cap on the right is what was there before. Bob includes crimp on connectors that will make future cap changes easier since they don't require soldering.

[whtboy]

Here's another pic of the same thing from a different angle.

[whtboy]

And a pic of one completed network

[whtboy]

Just in case my experience sounds a little lackluster I should add I'm using a (relatively new) Yamaha AV receiver that leaves a lot to be desired. It's got a serious noise problem that is audible at normal listening levels and on top of that my living room is pretty small and has a nasty small-room echo I've been working to eliminate.

I've been toying with the idea of bi- or tri-amping these guys with some of the plans available from Rod Elliot here: http://sound.westhost.com/

I've already got the board for a Linkwitz-Riley active crossover but I think I'm going to live with my current setup for a little while, do an A/B test with a real amp and see what I get.

I want to say thanks to Jeff, Bob, Put and everyone else who shared their time, experiences, insight, knowledge, etc. - it definitely made me much more confident in the purchasing/upgrading decisions I've been making.

Thanks guys!

-jacob

[Daddy Dee]

Jacob,

Congrats on your project. Pics look great.

[whtboy]

One more positive note - I've been sitting in bed reading, listening to ...and Justice for All from another room, and I realized I can pick out the individual drum sounds much better than before. I didn't notice it at first, but just casually paying attention, it is much easier for me now to listen to a section of music and hear how it is played.

I often struggle to figure out which drum is being hit, or to differentiate between a crash and a half-open hi hat when everything but the initial sound fades into the flat noise of the music. I can tell much more easily now, and this is on a badly scratched CD that was burned from a lame-encoded MP3 at 160 kbps!

Also, the cymbals on the first few tracks of The Wall are simply incredible - so dynamic and real.

These speakers don't sound anywhere close to how I imagine an ideal speaker might sound, but I'm extremely happy with my setup all things considered.