TymoTee Desktop Monitor
  • Tymphany TPY04W08O001ES 4" Woofer
  • Dayton ND20-FA6 Tweeter
  • 6.0 Liter Box with 1.5"D X 4" Port
  • F3 = 59 Hz, Fb = 65 Hz
  • 1/2" Baltic Birch

Updated Version

I got a consignment request from a guy who wanted a "kit" that he could finish himself to match his office furniture. But he didn't want to build the box himself. I looked through my inventory and found another pair of the Tymphany buyouts. Since I was never really enthralled with the rear mounted Dayton on the original Tymotees, I decided to build a second version with the ND20-FB6 I used in the Amethysts.

I changed the basic box shape a bit, reducing the volume and the height. I chose to offset the tweeter as it would have wound up almost equidistant from all three edges. The new crossover is pretty simple. Ultimately handing off at about 3000 with fairly benign impedance curve. Both coils are 20 gauge air core. All resistors shown are real and reflect the DCR of the inductors used.

Version 2 is a distinct improvement over the original. Most of that is attributable to the ND20-FA6. It's simply smoother and cleaner than it's FB brother. The overall presentation is smoother, the smaller box doesn't seem to affect the bottom end. (Ample but not overwhelming). In side by side comparos, Version 2 is cleaner, more relaxed and less fatiguing.

April 2011
Tymphany TPY04W08O001ES 4" Woofer
Dayton ND20FB-4 Tweeter
6.5 Liter Box with 1.5"D X 4" Port
Fb = 63 Hz; F3 = 57 Hz
1/2" Stock for box


Since nowadays everybody seems to have the pecuniary tendencies of Scrooge, and I needed some shop therapy, I decided to do a quick and dirty buyout project with drivers in the bin.

Other than having the longest model number on record, the Tymphany 4" looked like a cool little driver. Ample Xmax, small size, decent sensitivity. Thought it might make a nice little monitor for a graduation gift.

Looking through my box of small tweeters, I found a pair of Dayton ND20FB-4. I had never used these before -- mainly because of the rear mounting scheme. But it occured to me they would be easy to mount with some hot melt, placed through the woofer hole. Unlike the ND20FA-6, this tweeter takes a 1 3/8 hole from a spade bit, and is the perfect depth for 1/2" baltic birch. I soldered the leads on before I put it in the box.

The other issue with this rear mount is finishing. I figured I'd have to put the finish on the baffle before installing the tweeter, not much room for masking. I decided a quick roller job with Duratex would do it.

The Tymphany is probably better suited to being a high SPL mid in a 3 way. Most likely it's intended purpose. But I found a 6 liter box with the stock 1.5" by 4" flared port from PE would produce a decent bottom end. It seems like a pretty big box for that little driver, but it sounds just fine. Roughly the same bass output as the Amethyst (but 8 Ohm) and the same box volume as the Po'tables but cheaper and less sesitivity than either.

Since it was a windy day, and this is a lightweight box, I decided to measure using ground plane methods. The Tymphany sure looks promising being nearly flat out to 5000 or so. The ND clearly needed something at 3000 or above. There is virtually no offset in the acoustic centers -- probably due to surface mounting the woofer and the recessed horn load on the tweeter.

Crossover and Listening Impressions

I found a variety of potential crossover points but finally decided I liked the model at 3500 Hz the best. The woofer coil is an 18 ga laminate core. The tweeter coil is 20 ga with a 1.5 ohm resistor in series. Pretty simple and cheap. I threw some mattress topper in the box with a fistfull of dacron batting and buttoned them up

When I got around to building and tweaking, I started with 5.7 padding resistor. By the time I got done, I settled on 8. This variant of the ND series seems better off axis than on axis. Just a bit edgy and gritty for my tastes. The result is voicing a bit on the warm side. Definitely a trade off between ultimate "sparkle" and too much glare. Again, not uncommon (in my experience) with low cost tweeters. Considering how the Tymphany measured, I think the ND16 would work with it just as well. One could probably go up to 4000 and crossover there if you choose. Of the three ND tweeters, this would be my third choice.

The Tymphany actually does a pretty nice job. Bass is decent. Probably about 3-4 db baffle step. I belive the 5 mm Xmax. The driver works pretty hard, but certainly can play loud enough for my shop. Typically nice & relaxed paper cone midrange. As a pair they do a nice job of imaging and presentation. There are a couple of edgy notes when they are pushed too hard. Considering the drivers come out to about $20/box, I wasn't expecting reference quality. Very good for the price. Overall a nice pair of "gifters" that will make some young graduate very happy.