Best Bass for MarkAudio CHS-70 Drive Units

Returned after a lengthy period with a vengeance. Visaton BG20 TQWT well underway (info/pics to follow), I also had a hankering to build a full ranger with a small HQ Drive unit. So after some research enter the gorgeous looking CHS-70 from MarkAudio. A quick forum search has indicated several decent designs suited for the unit, so rather than hijack another thread, my question is which one is going to yield the best Bass response :confused:
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As best i can tell CHS-70 is Pluvia Seven without the dimple on the dustcap.

Are yours without the dustcap dimples? Only ever available in the UK AFAIK (and what i have).

This unit is more like the old EL70 in terms of box needs. Many EL70 boxes can be used with no changes.

Scott & i are for instance going thru the Lake District set of plans and tweaking for the CHS70/Pluvia Seven.

Here we have only tried it in the Frugel-Horn Mk3, and a set of dCHR-Ken70 enclosures (good but not quite optimumal).

Best bass response likely from Frugel-Horn Mk3. Then the Pensil. I'd put up the Mar-KenP7mT (not drawn yet) as the box with the lowest diffraction signature, and likely the most finesse.

these sound great


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Hi guys,

I'm novice and just starting my first DIY project. I've some Mark Audio Pluvia Seven (CHS-70) drivers and wish to put these drivers in Back Loaded Horn Design:

Please describe me pros and cons and suitable calculations and dimensions. All recommendations will be welcome.

What about if I laser cut internal parts from XPS foam? Any suggestions or proposals?

I wish to try also mini Karlsonator and compare these two designs.

Thank you!
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Back Loaded Horn Design:

That isn't really a horn, it is a badly designed TL.

The Pluvia Seven/CHS-70 has T/S very similar to the EL70 so can be put into the same enclosures (some may need a tiny bit of tweaking to be optimal). For instance, Wiggle's Derwent are from the Lake District series for the EL70.

Horns to consider would be Frugel-Horn Mk3, or Woden Maeshowe.

We 1st tried this driver in FH3 with excellent results and will put out set of 4 into some Thirlmere-R enclosures we have here.