2,5 way tower speaker kit diy project

[Thorsten Loesch]

I will adamantly state that no Wavecor thus far will ever sound better than the classic SS Rev 9900. It is 30 yrs old, and still state of the art in performance.

Hmmm.

Which wavecor so far did you try?

The 9900 is an ok tweeter, but I'm not blown away especially in light of the cost.

Wavecore is much lower cost and the waveguide makes it preferrable in my books.

Thor

 

[Wolf]

I had a look at the other 'design' SB Acoustic TMM, and I'm not happy with the xover schematic. The way it's wired will place the 2 resistors and shunt coil on the tweeter circuit directly across the amplifier terminals in series. This is something that could cause a fire under higher outputs, and requires heavy heatsinking and larger higher power resistors. The fact that the designer did this is short sighted and uninformed about how speakers, components, and amplifiers act in cases as these.

One of the rules in speaker schematic design should be to not ever bypass the tweeter's first series capacitor, in 2nd order electrical circuits or higher, unless special allowances are made. The resistors must be at least 25W, mounted on a heatsink, and also be external to the cabinet for adequate air flow as well as avoiding contact with damping materials.

If you have a series resistor before the xover, then it can be bypassed with a cap so long as there is another cap in series without a resistor across it.

Why this is a problem? Bass frequencies are blocked in Tweeter filters by capacitors. If there is no block of lower frequencies then full amplifier bandwidth can be fed through a circuit. This is why an Lpad is after the xover to limit bandwidth. The amplifier is just supplying the power to the load presented.

In that schematic, you have a coil and 8 ohms across the amplifier. What do dummy loads do when testing amps? THEY GET HOT! Without the capacitor to limit the bandwidth, your house and all of its belongings could be destroyed in the process.

All of you builders and both up-and-coming and experienced designers should be made very aware of this. Please do not do this.

EDIT: I would also like to add that it can also increase HD in the tweeter or mid by allowing the bass range to pass through the tweeter if this is a 2nd order electrical filter. Even if minutely passed or at an attenuated level, this is bypassing the highpass that is cleaning and protecting the driver in use. Likely a case for some large IMD too.
I've even seen someone use a resistor across BOTH caps in a 3rd order electrical network. It's dangerous to both user and driver, and I can't understand why it would be viewed as safe or okay.
The 'benefit' as this looks in sim is not worth the hassle or caveats.

 

[Wolf]

Hmmm.

Which wavecor so far did you try?

The 9900 is an ok tweeter, but I'm not blown away especially in light of the cost.

Wavecore is much lower cost and the waveguide makes it preferrable in my books.

Thor

The 9900 has a waveguide. The face is dish shaped. The Wavecor tweeters may sound benign, but have very wobbly response profiles. Place the Rev in a cab, and it's fairly easy to get flat and accurate response like Jeff B did in his Spirit Winds design. I have rarely heard cymbals with as much clarity as the Rev reproduces them, and certainly not ever from a Wavecor.

 

[Thorsten Loesch]

The 9900 has a waveguide. The face is dish shaped.

It has a 2-step waveguide. You can both hear the step and see it in the FR.

The Wavecor tweeters may sound benign, but have very wobbly response profiles.

I am not sure what a "wobbly response profile" is. The WC measures like this:

(source: Test Bench: Wavecor TW030WA12 30-mm Cloth Waveguide Loaded Tweeter

And here the SS from their marketing material:

I fail to see anything that would recommend the 2.5 times as expensive SS over the WC.

Place the Rev in a cab, and it's fairly easy to get flat and accurate response like Jeff B did in his Spirit Winds design. I have rarely heard cymbals with as much clarity as the Rev reproduces them, and certainly not ever from a Wavecor.

Well, I never heard cymbals sound like cymbals from any cloth dome. But that's just me. They do tend to be more forgiving of poor recordings though.

Thor

 

[Wolf]

The Rev measures better than that in reality, and the Wavecor have not measured that good in 3rd party measurements with 5dB swings.

 

[Thorsten Loesch]

The Rev measures better than that in reality, and the Wavecor have not measured that good in 3rd party measurements with 5dB swings.

The Wavecor measurements I posted ARE 3rd Party (Voice Coil).

Here a 3rd party measurement of D2905-9900:

The same glitch around 10kHz can be seen.

I have no evidence from 3rd party measurements that the SS 9900 measures better than it's datasheet and the WC TW30WA12 measures worse than it's datasheet.

I'm not really interested in a contest about this. I have no stock in either company nor do I use either driver. I have other preferences and tend to get custom designs if I need drivers. I prefer Planar's, Ribbon's, Ring Radiators and Focal style inverted domes.

But if I were to make a mainstream style speaker, I'd select the WC over SS and not just because of the budget.

Thor

 

[biniek]

Hi
I got rid of tube amp and now i have the CA 651W poweramp. So this is much more powerfull amp
Thinking of Zaph ZRT 2,5 way closed
Are they any good?
Cheers

 

[Wolf]

You will lose a lot of low end if you seal those up.

 

[Roland68]

Hi
I got rid of tube amp and now i have the CA 651W poweramp. So this is much more powerfull amp
Thinking of Zaph ZRT 2,5 way closed
Are they any good?
Cheers

If you want a 2 1/2 way speaker, then look at the SB Acoustics Arya, or the Rinjani with Satori chassis.
The Arya is within your budget both as a kit and with individual parts.
The Rinjani is a little over your budget with some parts, but these chassis are in a different league. You can later upgrade the Rinjani to the BE version with a beryllium tweeter.
Arya
Rinjani