Zaph's ZTD3 - tweeter (un)availability

[eddo]

Hi all, first post on here...

So I've found myself in an interesting position, having ALL of the parts to build Zaph's ZTD3 except the NT1 tweeter. Madisound is out of stock on the NT1, and from my chat with them it seems dicey as to when/if it will be restocked (Aura factory relocation). I hope to wait and see if I can get my hands on a few later in the spring, but I'm not going to hold my breath.

I'm wondering if anyone would be willing to suggest a possible workaround. I know that this design is optimized for the NT1, and any changes will require mods to the baffle and x-over. John does not recommend the ND20, I assume because of the impedance difference and higher distortion (it obviously isn't a drop-in solution). I'm just trying to find a suitable replacement, as I really like this design and have the components sitting here begging to be assembled!

Any input form John would be greatly appreciated, I don't want to perturb his carefully thought out design with a poor tweeter choice.

Thoughts anyone?

[Luke G]

I was asking about it as well...

http://www.htguide.com/forum/showthread.php4?t=29460&highlight=aura

[eddo]

I guess I didn't search this topic thoroughly, thats a bummer. Oh well, I'm always one to improvise if the situation calls for it. Perhaps others interested in this design would like to brainstorm and come up with a potential solution? I'm going to build this one way or another...

[JonP]

Hang in there...

Problem is, changing a tweeter in a design pretty much demands a redesigned crossover. Changes to the tweeter side, and likely also some smaller changes to the woofer side. Unless you are very lucky, and find a tweeter that is virtually the same in it's characteristics, that's what it's going to take.

So, that's pretty much a new design.

That being said, probably the closest similar tweeter (and it's probably not close) would be the Dayton NT20-? that shares the hole mounting frame. Zaph's design not only has a tweeter with particular electroacoustic characteristics, it has particular physical ones, too. (3/4" dome, ultra small hole mount body) Not many that you could space that close... maybe just those two.

Anything else, it's a bigger tweeter, farther center to center spacing and thereby need for lower crossover, larger changes to the woofer filter... now, it's a different speaker entirely...

[jkrutke]

I've got some Hi-Vi T-20's on the way for testing, and also a pair of TN-25's. The TN-25 has been out for a while but I've never tested it.

If the T-20's don't suck, maybe I'll consider those for the design though I'd have to cut a new baffle, get some RS52 and RS180 drivers in stock again and essentially redesign the whole thing. I could potentially just cut a baffle and stick the tweeter in it to get in-baffle data, but I'm a little uncomfortable recommending it without at least some listening tests first. A complete redesign is a lot of work and may never happen.

Those who have all the ZDT3 drivers should save the design to their hard drive at this time. It's likely to be pulled soon. ZBM4 also. Mostly because I'm tired of hearing about these supply issues.

I've been hearing the words "Aura" and "factory relocation" in the same sentence for over a year now. It's obvious to me that the company is having serious problems. I doubt if I'll use any Aura drivers again in the future even if the company seems to come back from the dead. It's too bad, some of them are nice.

[jkrutke]

I may be redesigning for the PE rear mount ND20 after all. See this post.

[eddo]

Just looked at the Zaph blog, that really made my day . Thats great that the ND20 shipping situation has improved, looking forward to building this design.

Many thanks to John. I'm sure others will also be happy about the improved outlook for the ZTD3.