Little Dayton rs100/Vifa ox tapered TL build thread...

[jamikkim]

Hey guys...!

This little project is finally beginning to resemble a pair of speakers instead of a couple of design sheets in Excel and on paper... :o

I had some fun with the rs100 in the enclosure before it was glued fully, and it sounded fairly terrible...I'm glad I still have things to do on the enclosure, such as chamfering the backside of the baffle and adding the lining and stuffing inside...

I'm actually pleased I used the 16mm panels, since the TL divider acts as a good brace, and 1'' MDF would have left the magnet almost inside the hole for the driver, and given the slenderness of the inside (3.5''), that can't really be good for the sound quality...

I have a little idea for where the crossover will go, since I didn't want to just lengthen the bottom of the box...


The last pic is an amp from a pair of computer speakers inside a slightly more attractive enclosure...

[jamikkim]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

hey everyone...

A little bit of progress, I made the holes for the "binding posts" and added some felty kind of stuff to the inside of the enclosure (it does seem to work quite well). The binding posts are an improvisation of sorts, since a normal set of posts cost $10 ea. meaning $20 for the speakers. I looked elsewhere in the store and found these banana plug to bp/bare wire cuties for $3 single. They'll require a bit more work to make them air-tight and to solder the wire to them, but will function exactly the same from the outside, for $8 less than "ideal" ones. It turns out they fit just nicely in the holes I made for them... ;)

Next up is sanding the "1/4 inch bevel" from the baffle...hmmm... I might be able to make a cone something with a scrap of MDF and some sandpaper...

[tomzarbo]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

Lookin good so far. I like the RS100's myself. Are you using the 8 or 4 ohm version?

TomZ

[jamikkim]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

Both woofer and tweeter are 4 Ohms. The design has full BSC, so I wonder how they'll do with regards to the amount of bass...

I tested the rs100 again now with the chamfer and the padding on the inside; the sound was notably better, though still some bass missing due to non-glued panels => air leaks. I'll have to check everything before I glue the last panel, because although I can fit my hand through the 89mm hole and reach all around inside there, it will be difficult to do anything in there...

[honfatboy]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

Could you post your plans? I've got a pair that I need to do something with.

[jamikkim]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

Um...I will need to scan the new plans I made for the 16mm MDF - I have some older plans that use 1" panels, but I think that is slightly too thick. Note there is some finicky design work with them since I didn't have a router, so I hope they aren't too complicated for you...

[[email protected]]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

how did you design the ttl? i have used the ox and really liked it. its a tough little guy. will you be able to post a fr graph when completed?

[jamikkim]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

hey everyone...

I fitted one side together on the weekend because we all try to listen to our speakers as soon as there is the slightest chance of functionality... ;) I have to say I was disappointed with the response, it was fairly "bright" and "harsh", perhaps a little shouty as well, something I really didn't expect from a design that is supposed to be "flat". There are some things I am guessing could be the problem:

- The tweeter chamfer is not done.
- There is an error in the crossover circuit.
- I don't know what "flat" sounds like... ;)

Any ideas what may be the cause?

edit: arlis, Pete did most of the TL design work for me using MJK worksheets, so thank you Pete!

edit2: oops, I'd better show you guys where the woofer tweeter hook up points are on that crossover!

edit3: hon, are you still around? I have some proper scans of the design plans now if you (or anyone else) would like them...

[Pete Schumacher]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

What are you using for stuffing? Most tapered TLs have a fair amount of stuffing in the first half of the line. Without it, the response will be terribly ragged.

[jamikkim]

Re: Little Dayton rs100/Vifa ox tapered TL build thread...

Well, that was the other thing - the only stuffing in there at the moment is air... :o I haven't really listened too much to bass response since the panels aren't glued and there are trim bits which I haven't made up yet, so leaks everywhere! I won't be "analysing" the TL's response until that is more complete - just my crossover design and tweeter bevel at this stage...

I think the harsh/bright problem is in the mid-high range, mainly the tweeter, given that the woofer rolls off from about 2kHz (this sounds correct as there is not much intelligibility of "s" sounds from the woofer) . So far I haven't found an error in the crossover; it's like proof-reading your own writing though.

edit: new week: I tried both speakers on their sides and sat the tweeter on top. The sound was much nicer, it still sounds like more top octave and a dip in the lower treble due to no reinforcement from the baffle. Based on this listening test I think the crossover is ok, and that the still rough tweeter hole may have created some issues. I think I may have also had the tweeter polarity the wrong way last week, which is really embarrassing... :o