Large Advent clone

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Hi excellent idea. They are still one of the oldie goldies.
First you start with the drivers, then you copy the box and thirdly you copy the xo unless you are able to design an updated version. Lot's of info on where to get the stuff but if you really want a set of large Advents, you might just want to buy a set. You can't just clone them. Unless by clone you just mean build a 10" 2 way speaker?
 
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Well, there are some so called drop in replacement woofers. Might be a place to start.

Advent Factory 10" Large Advent, New Large Advent, The Advent, OEM Woofer P001-31858: Amazon.ca: Electronics

Problem is, we have learned much about loudspeakers since those days. For example a 10" woofer is difficult to carry high enough to xo to a cone tweeter. Sure it worked back then, to a point, but with what we know now, we want a smaller woofer for a 2 way and by the time you get to 10" you may as well be thinking 3 way.

My large Advent cabinets came with the tweeters but no woofers. They just kinda sat around getting dusty until one of the very generous members here set me up with refoamed woofers. The xo's were easy to recap and low and behold, they had a new life.
 

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You can't make a true clone. Manufacturers no longer make "acoustic suspension" woofers with highly compliant spiders and surrounds. This makes it impossible to achieve the low Fs in a smallish sealed box. You would need to apply a Linkwitz transform equalization.
 
You can't make a true clone. Manufacturers no longer make "acoustic suspension" woofers with highly compliant spiders and surrounds. This makes it impossible to achieve the low Fs in a smallish sealed box. You would need to apply a Linkwitz transform equalization.

I can give 1 hint. The free air resonance of an Advent woofer is 15 Hz. In the box, the system resonance goes up
to 38 Hz. Voice coil wound on a copper form appears to be 1/4" exposed on each edge. Would that make xmax
12mm?

I have re-foamed 6 or 8 of them and it is not difficult at all. I removed the masonite rings (old style), cleaned
them off and glued them back to the frame with RTV. The glue from foam to cone is good with pure latex - never
hardens.

 
There are several articles discussing convering the Large Advent cabinet into an EconoWave design with a 12" SEOS waveguide and a 1" compression driver. Good reviews on sound quality.

The 10" woofer SB29NRX75-6 models to -F3 = 43Hz in a sealed 1.5cuft volume.

New Large Advents: 14" w x 11 1/2" d x 26" h
about 1.5cuft usable internal cabinet volume.
 
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The Humanspeakers 10" Epicure-style woofer has similar specs and roll-off behavior to the Advent metal-framed woofer.
The Peerless 1.5" wide range drivers(TC5) would work, the neo may be sensitive enough. The TC6 range are more sensitive and easier to work with.


This will of course not be a clone, but a retro-styled copy(which definition allows improvements in crossover design, allowing for baffle diffraction effects and modern placement).
 
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There are several articles discussing convering the Large Advent cabinet into an EconoWave design with a 12" SEOS waveguide and a 1" compression driver. Good reviews on sound quality.

The 10" woofer SB29NRX75-6 models to -F3 = 43Hz in a sealed 1.5cuft volume.

New Large Advents: 14" w x 11 1/2" d x 26" h
about 1.5cuft usable internal cabinet volume.


I have that SB29 in 33 liters with an Aperiodic vent. In-room f3 is 37 Hz! It doesn't do mid or upper bass very well though. Take a look at the Vifa/Tymphany/Peerless NE 265W 4 and 8 Ohm. There is a member here that just bought 4 pieces of the 4 Ohm version wholesale; I may want two of those wants he receives them, you may want to consider the other two? Over half price off; GREAT deal.

You would probably get good results with this large tweeter

Audax TW034X0 1.3" Textile Dome Tweeter


Or, get a Mark Audio or Fostex FR that can easily do 1 KHz to over 20 KHz; maybe start looking at the 3 inch FR's?

Just some random thoughts that came to me immediately.

I had the second generation Advents; I think the box size was 1.7 ft^3; same as the AR3a. the cap was electrolytic; the inductor was 18AWG I think and about 0.33 mH??? Memory...not what it used to be. They had a 3 position switch in the back. One position I think shorted out the LP inductor called "extend"; another position was normal and the last position put a cheap sand block resistor in series with the tweeter.

Just a quick reaction here; the SB29 does GREAT lower bass but no way would it do justice to a 10 inch 2-way; just doesn't have the finesse so to speak to pull that off.


best of luck!
 
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... "The mid-range dome tweeter provides a quality sound comparable to the famous fried egg tweeter by Henry Kloss (Advent, KLH fame)" ...

This is a partial quote on the Madisound site about the Audax 1.3 inch mid/tweeter. I used this exact same tweeter in a 10 inch 2-way with a Pioneer poly' cone, foam surround. It was WAY better sounding than the 2nd gen. Advents; I compared them side by side. The Advents just were too bright and the bass took way too much power to get them really going in my opinion. Still; for the money and that time frame they were very good at what they did.
 
I had a pair of these and sounded pretty nice with big amplification. I ran them with a Sony V7 150 wpc reciever, very nice. Less power not as nice. Eventually went to a pair of Marantz 880 3ways which I thought bested the Advents. But then again I'm dating myself.
 
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I only had 35 Watts; not enough for the Advents. One of my buddies had 100 Watts; they woke up for sure but I still think the tonal balance was way off by today's standards...FWIW...

I'm almost 65; dating myself, hah! I don't care! My boss had some of the very first AR3a's...WAY better than the Advents...but; the Advents did do a good job for the money; I (almost) always like 3-ways over 2-ways (exceptions of course as always)...
 
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