Orthodynamic Roundup - Page 811

Heh..am having a ball with all the ortho goodness that I have currently at my disposal..at least for the next couple of weeks.

Look at what's happening here..an ortho orgy...picking on the lonely stat

looks like a whole lotta goodness ..dB

Modding vintage cans?

Specifically, I picked up a pair of Realistic Nova 44 quadraphonic headphones at a thrift shop and was thinking about replacing the drivers with more modern ones and wiring them for stereo. Is there any benefit to having two drivers per side in a stereo configuration?

Here's some pics of inside the cup (please excuse the quality):




I was thinking about using these planar drivers but I read that they need a very small cavity to have any usable bass. Then I thought about filling the cavity somewhat by cutting triangle pieces of self-adhesive vinyl damping sheet to fit the top and bottom of the cup. Then I would cutout progressively smaller pieces and stair-step them up to the back of the enclosure. This would give me two drivers per side in what would effectively be a horn-loaded enclosure. Does this sound workable or would I need to stick with dynamic drivers? If so, what's a good source for them?

I'd be running these off a cheap HotAudio USB DAC/HP amp combo unit that I bought off of eBay.

Like I said, I enjoy tinkering so any labor involved is not really an issue. I'm just wondering if I could have my fun modding these and the results be worth the $$$ cost of the drivers. They're not much but I don't want to buy them if a total disaster is a foregone conclusion.

I can guarantee that you'll enjoy the process and learn a bit about tuning the sound of headphones but that doesn't mean that they won't be a disaster. I say go for it.

Yeah, I'm definitely going to try something with these. I'm just a little gun-shy about the SFI drivers because of all I've read about them needing very shallow enclosures.

So I guess my primary questions are...

• Should I go with the SFI's or should I go with dynamic drivers?

• If I buy the SFI's (taking into consideration my cheapy amp) should I get the 120ohm or the 32ohm versions?

• If dynamic drivers are recommended, are there any good sources for decent yet inexpensive ones?

are they've been broken so you try to replace em with somethin else ?

you should try both of em, but base on what you had saying maybe 32ohms are more suit...

Cable panic!

I need a new cable on the Dual. The Dual is dual entry. What cable should I use? My cable store stores Mogami. Is there a good Mogami cable I can use?

Well, you're going to use 2 drivers per side, so the volume of the cup is less of an issue and you can connect each side in parallel for a 60ohm load with 120s or series connect the 32s for a 64ohm load, so the differences are negligible once actual impedance is factored in. Ask if he'll match drivers for you for an extra $5 or $10, it will be worth the extra cost because you could end up with a 10ohm swing on the 120s and have a 4-5ohm delta between the two sides after paralleling the 120s. Series connecting 32s would push the delta even wider as I've seen them measure as low as 27ohm and as high as 36ohm in my 15 pairs. I was able to match a quad to within .3 ohms on the 120s, but I was just lucky as I had a lot of variation after that.

Mogami 2893.

Well I'm not really back, but I just finished recabling a pair of HP50 I got a while ago and stopped by to check how things were going.

No, the search engine is not self-updating, I mean it could be, well let me set it up so that it is, at least for this thread.

Anything I missed these past few months?

Edit: the index for this thread is now set up so that it's updated at midnight (CET time) every day, if you need more frequent updates just ask

I'll order 3 meters of Mogami then, and a Neutrik plug. What's the best thing to do at the Y-split since the cable cover has to end there? Is there anything better than shrink-plastic?

I suppose then I'll get two bare cables going to each cup... do I need to do anything with them? Also, once inside the cups, something to act as a "stopper" would be good. Ideas for that?

I use two different sizes of heatshrink tubing: a smaller diameter for the two smaller cables going to the cups, and a larger one to cover part of the bottom cable and the two smaller pieces of heatshrink. I usually sleeve the upper cables with cotton sleeves made from bootlaces.

Inside the cups, either use the smallest cable tie you can find, or very thin layers of heatshrink one over the other to form a thick ring.

For a classy Y Split, take the barrel of a spare plug and place that over the Y split, then heatshrink over that with some adhesive lined heatshrink. Another technique is to use adhesive heatshrink with plyers to clamp the middle closed over the y split.

A gob of hot glue serves pretty well as strain relief on a cable entry. It's on the inside of a cup, so looks don't really matter too much. Heatshrink the cable entry too though.

Do I need shielded heatshrink tubing for the short part going from the Y to the cups?

What two sizes do I need of the tubing?


I think I'll go look for pictures of both variations :-)