Tang Band W8-1772 Impressions.

[AstroSonic]

Response Plot Questions

Bob,

These drivers sure look promising: relatively even frequency response and T/S parameters allowing reasonable bass in manageable enclosures.

Regarding the response plots, are they for the raw driver or are your BSC and HF correction networks included? I wonder how audible the two HF peaks and the suckout between 4.5 and 6.5 kHz will be. The curves for 15 and 30 degrees off axis look very promising.

Thanks for taking the lead on this.

Regards,

Bob P.

 

[Godzilla]

>>> Now one stretched out so the details are visible:

Many thanks Bob! The only thing i don't like about the measurements is the dip at 150hz... otherwise it looks great.

Godzilla

 

[Bob Brines]

Bob,

....Regarding the response plots, are they for the raw driver or are your BSC and HF correction networks included? I wonder how audible the two HF peaks and the suckout between 4.5 and 6.5 kHz will be....

Bob P.

No BCS, No EQ. The driver is in an MLTL, not on an EIC baffle.

The 4.5kHz notch only starts to appear in the 30* plot, so at normal listening angles -- 10-15* -- it is probably not an issue. The 6.5kHz notch coincides with the sibilance peak in most pop recordings. The effect is softening of the "s" and "p" sounds. Interestingly, this notch appears in every driver I have converted to phase plugs. I have to wonder if it is not the effect of the phase plug in THIS driver. The HF peaks are so narrow in terms of octaves, that you will probably not hear them. Look at these peaks as a continuing of the general rising FR.

Bob

 

[Bob Brines]

>>> Now one stretched out so the details are visible:

Many thanks Bob! The only thing i don't like about the measurements is the dip at 150hz... otherwise it looks great.

Godzilla

That dip is floor bounce. You should ignore anything below ~500Hz as artifacts of the cabinet.

Bob

 

[rdf]

Thanks for posting this, nice work & driver. Is the elevated frequency response above ~200 Hz a baffle step artifact?

 

[Bob Brines]

Thanks for posting this, nice work & driver. Is the elevated frequency response above ~200 Hz a baffle step artifact?

Yep! That's what baffle step looks like.

Bob

 

[speakrsrfun]

Anyone have an idea what retail will be on these, they look good for next years project to be started in January LOL. Take care....

 

[Bob Brines]

Anyone have an idea what retail will be on these, they look good for next years project to be started in January LOL. Take care....

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-893

Bob

 

[Holger Barske]

There's a self-taken set of TSP on the German distributor's page: http://oaudio.de/Lautsprecher-Chassis/Tang-Band/Breitbaender/W8-1772::664.html
Meets Bob's measurements quite nicely.

 

[speakrsrfun]

Thank you sir I appreciate it, good lookin out.

 

[MisterTwister]

Is the elevated frequency response above ~200 Hz a baffle step artifact?

I think baffle step effect occurs much higher in frequency.
looks like it happens at 400-600hz region here.
and rising frequency from 2k and above is energy storage or cone resonance, whatever you call it.

 

[audiokinesis]

Bob, your plots look similar to what I got. No single curve looks really great, BUT the average of all the curves - which corresponds reasonably well with the power response - is quite good. Something else educational here: the on-axis curve does not begin to paint a complete picture, nor does any other single curve.

 

[konut]

Duke or Bob, would these be a drop in replacement for a Visaton B200?

 

[audiokinesis]

Konut, I don't think so. The Visaton has VERY different T/S parameters. In my opinion not even the W8-1808 would be a drop-in replacement. I think the Hemptone (from the makers of Tone Tubby) 8" fullrange may be a possible alternative to the Visteon. Supravox makes another possibility, the 215 Bicone.

Duke

 

[konut]

Thanks Duke.

 

[Holger Barske]

There is nothing like a "drop in replacement". A different driver makes a different speaker.

 

[konut]

Well yeah. I was hoping for something with less of a peak in the 4k to 7k range, and a little more efficiency than the B200 that was the same dimensionally yet was close enough in T/S parameters to drop in my aperiodic boxes. Hope springs eternal.

 

[hm]

Thanks Bob,
for the detailed measurement,
my Saxophon and the RDH20
horn would work.

 

[freddi]

hey Bob - how far does it travel til the back plate is smacked? - is power handling good on drums and bass? - - BEST, Freddy

 

[Bob Brines]

hey Bob - how far does it travel til the back plate is smacked? - is power handling good on drums and bass? - - BEST, Freddy

I didn't measure the distance, I just noted this while setting up the break-in frequency/power. My guess is that it is in th 5-6mm range. It really shouldn't be an issue at anything but dangerous SPL levels. Note that in my cabinet, a stereo pair will produce 105dB/w/m at 10 watts exceeding Xmax below 30Hz. Unlike Fostex or Lowther drivers, the TB really needs a high pass filter to eliminate infrasonics.

The 1772 is a very clean, low distortion driver. Under normal full-range rules, dynamic compression should not be an issue. However, Doppler distortion is still an issue, even more so since there is +/- 3mm travel available. I can hear this as I progress through Vivaldi > Beethoven > Pink Floyd > Led Zeppelin. Dynamics in the lighter stuff is super, but the heavier stuff starts to get muddy.

Bob