Tang Band W8-1772 Impressions.

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Jeez.....for a minute I thought I mistakingly posted on the Multi-way forum :eek:

Ok....once this Covid thing is over I will see the doctor and get my ears tested :confused:.....cos what I am hearing now sounds might fine........:cool:

... Didn't you enjoy those PRV wide-range drivers for a while?

My point being that it's difficult to know how well we're doing until we hear something considerably better.

It might well be the case that putting a bit of polyester wadding around the edge of the drivers improves the midrange, and some decent evidence has been supplied that suggests it might well be the case.

Given the low cost (heck, it might even be free - anyone else got a few bags of poly filling around?) of trying this, and the potential for serious improvement, I really think it's worth giving it a try.

As always, though, it's your system. If you like it how it is, that's fine by me. This is a simple thing to try, and might make something decent even better.

Chris
 
Not really into the maths.....just use my ears.
I tweaked the crossover to my liking, and today took a measurement of one side from 1m away.

I was expecting to see a hump at 1k.....but as you can see, pretty flat.

The dip in at around 500hz is the crossover. I can get this flat, but then vocals sound too chesty.

My intention of this post was not to cause controversy, but to give information on my experiences with this driver in this context.

As you say....to each his own, and there is more than one way to skin a cat........but if anyone is interested in my findings please get in touch.

Yes Chris....I happily lived with the PRVs for a few years. I got bored during this lockdown so decided to experiment. I still think the PRV is a great driver, and many may find the TB is a sideways step....but the treble to me is certainly a revelation.

Cheers

Vic
 

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frugal-phile™
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I think taking diffraction seriously...

There are 3 basic variations i do on my miniOnken alignment. A simple box (Classic Golden Ratio) which only supports a small amount of edge treatment (chamfer or roundover), the rectangular version with vents down the side and big chamfers on the side, and then the Trapezoidal variation (actually 8 “sided” once the heavy chamfers are added, and its plan starts to look like a crude teardrop). As you move along these the construction becoes harder but the diffaction of the box decreases and this is audiable.

dave
 
There are 3 basic variations i do on my miniOnken alignment. A simple box (Classic Golden Ratio) which only supports a small amount of edge treatment (chamfer or roundover), the rectangular version with vents down the side and big chamfers on the side, and then the Trapezoidal variation (actually 8 “sided” once the heavy chamfers are added, and its plan starts to look like a crude teardrop). As you move along these the construction becoes harder but the diffaction of the box decreases and this is audiable.
One thing I would add is that the W8-1772 has a very well designed flange on the frame that was obviously designed to make proper flush mounting of the driver from the outside easy right from the get go.

If you look at some vintage drivers like my Coral's (in my avatar) the frame design is a nightmare for achieving any sort of flush mount. It has a built in gasket on the front edge and the outer part of the frame then steps back and is non-circular, pulling out towards the screw holes - clearly designed to be mounted from behind the panel with the built in gasket sealing against a rebate made from behind the panel. The way it was done 40 years ago... The step back in the front also kind of dictates the panel thickness you can use if you did mount from behind, which is annoying.

But unless the bit of the panel that the gasket pushes against is really thin you're going to end up with the driver set back well behind flush which is not good. Too much back and you actually get a nasty cavity resonance across the diameter of the driver, and the further back the driver is the worse the time alignment will get with a tweeter. I ended up mounting mine on the front of the panel with a gasket behind the outer frame not using the built in gasket and letting them stick out slightly - not ideal but the lesser of two evils between mounted behind and in front, and it gives better alignment with the tweeter. True flush mounting would require a very elaborate and complex rebate and a cover ring to fill in the gap that was left. Not worth the hassle.

The W8-1772 on the other hand just needs a simple circular rebate on the front of the panel and will drop in nicely from the front perfectly flush, not be fussy about the thickness of the panel, and they've even gone to the trouble of making sure the termination of the surround cloth sits flush with the frame as well, which is both aesthetically pleasing and good for diffraction.

Like I said in my initial observations on receiving these drivers - a lot of thought and care has gone into their design, right down to the flange - they capture the essence of the vintage full range driver while at the same time out performing most comparable vintage drivers and applying some more modern ideas to the details of the design like diffraction minimisation around the flange and frame, under-hung voice coil, neodymium magnet, inductance shorting ring etc...
 
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Oh dear, that makes things even worse, adding a big dip around 3Khz and a response that is more bumpy above 3Khz.

Mandrake

This is what I'm getting from my no baffle 1772, one driver. 1m away....no eq.

Is this close to what your simulation shows?

Also, my comment on the multi-way forum was not relation to your diffraction theory, but the way they also pounced on my postings there.
 

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The thing with those simulations is that they assume the driver is completely flat.

Which is never the case. So, if the driver has a dip at 1kHz, the baffle step will take care of that and just bring it flatter.

So, just quoting simulations means nothing without having seen the drivers frequency response to combine it with the simulation.
 
About 7 years ago, a group of us did a direct listening comparison of the 1808 and the 1772, both just mounted in a simple open baffle.

Out of a 5 member panel, 3 preferred the 1808, mostly because it had a bit more sense of bass, but 2 of us (obviously one of the 2 was me) preferred the 1772 due to it’s favorable tone. Changing the mounting technique from an open baffle, to a full sized round horn, changed the character of the driver to one of which was a bit “polite” and dainty, to a thunderous monster of tone and delight.

I’m contemplating building a Voigt pipe as per Tech Ingredients. He recommends the TB W8-1772, but it would seem you’d recommend the W8-1808 for better bass. Or am I missing something?

Note that I’ve spent the last 20 years with a TL using two 6 inch SEAS woofers and one inch dome tweeter and I really like the bass performance. I also have fond memories of my first speaker build in the early 1970s using 8 inch Richard Allen FR drivers.
 
That doesn’t actually help me very much in deciding which driver to purchase. Perhaps I should purchase one of each and hope for the best ;-)

When I built my Richard Allen boxen in 1973 one cabinet was BR and the other was infinite baffle. I intended to replicate the box I preferred, but never got around to it. Bear in mind that an awful lot of my listening in those days was to mono recordings.
 
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