{"id":3522,"date":"2013-03-03T15:03:53","date_gmt":"2013-03-03T15:03:53","guid":{"rendered":"http:\/\/www.audioexcite.com\/?p=3522"},"modified":"2013-07-23T15:43:08","modified_gmt":"2013-07-23T15:43:08","slug":"new-kef-sp1632-driver-unit","status":"publish","type":"post","link":"https:\/\/www.audioexcite.com\/?p=3522","title":{"rendered":"New KEF SP1632 driver unit!"},"content":{"rendered":"

\u00a0Overview:<\/span><\/h3>\n

 <\/p>\n

I\u2019ve used concentric (co-axial) drivers from SEAS in the past and liked them, but unfortunately SEAS hasn\u2019t refined the concept much the last 15 years and there are not generally speaking many good concentric drivers available to choose between for the DIY enthusiast.<\/p>\n

One company that certainly has improved the concentric driver concept during the last two decades is KEF<\/a> and the relativity new Uni-Q drivers from the \u201cR Series\u201d are no exception. The \u201cR Series\u201d concentric driver inherits its technology in a simpler variant from the KEF<\/a> flagship loudspeaker the “Blade”<\/a>.<\/p>\n

 <\/p>\n

\"\"<\/a>
\n\"\"<\/a>\"\"<\/a><\/strong><\/p>\n

Top:<\/strong> KEF “Blade”<\/p>\n

Left:<\/strong> KEF R300<\/p>\n

Right:<\/strong> KEF R500 and R900<\/p>\n

Here\u2019s how KEF<\/a> describes the new \u201cR Series\u201d concentric driver unit:<\/p>\n

“The new Uni-Q MF\/HF driver array is a masterpiece. Midrange response is amazingly fast and clean, thanks to a braced magnesium\/aluminium alloy cone, with KEF\u2019s Z-flex surround smoothing the transition to the front panel and a sturdy die-cast aluminium chassis that prevents resonance being transferred to the cabinet. <\/em><\/em><\/p>\n

At the acoustic centre of the midrange cone is the sophisticated vented tweeter that endows KEF Blade with such startlingly pure HF response. With a large neodymium magnet and a computer-optimised dome structure so stiff that it operates pistonically over its entire working range, the upper registers are articulated with flawless precision \u2013 and to capitalise on Uni-Q\u2019s point source characteristics, KEF\u2019s \u2018tangerine\u2019 waveguide helps to disperse the higher frequencies evenly across a wider angle to flood the room with an intricate and refreshingly natural soundfield. <\/em><\/em><\/p>\n

Operating together as a single, perfectly integrated voice, the array as a whole delivers a sweet, accurate sound of unprecedented clarity.”<\/em><\/p>\n

The KEF SP1632:<\/span><\/h3>\n

 <\/p>\n

\"\"<\/a>\"\"<\/a>
\n\"\"<\/a>\"\"<\/a>
\n\"\"<\/a>\"\"<\/a><\/p>\n

(click on picture to zoom)<\/p>\n

Top left:<\/strong> With design ring<\/p>\n

Mid left:<\/strong> The”tangerin” waveguide<\/p>\n

Lower left:<\/strong> The “Blade” Uni-Q exploded driver view (picture borrowed from the KEF website)<\/p>\n

Lower right:<\/strong> The SP1632 Uni-Q exploded driver view (picture borrowed from the KEF website)<\/p>\n

The KEF SP1632 driver unit used in the \u201cR Series\u201d is a 5\u201d mid-range driver paired with a 1\u201d tweeter placed in the centre of the cone. This driver can\u2019t be used for mid-woofer duties, since it\u2019s a pure mid-range driver and consequently it has to be used in a three way loudspeaker design.<\/p>\n

I intend to use the KEF SP1632 in a small three way called \u201cConcentric Three \u2013 M5\u201d<\/strong><\/span>.<\/p>\n

Note!<\/strong> The KEF SP1632 driver isn\u2019t generally available to DIY:ers. Either it has to be stripped from a loudspeaker in the \u201cR Series\u201d or ordered as a spare part, but this requires a valid \u201cR Series\u201d serial number in order to be able to obtain the driver.<\/p>\n

T\/S Parameters:<\/span><\/h3>\n

 <\/p>\n

\"\"<\/a><\/p>\n

Even for a 4 Ohm driver unit it has a low voice-coil DC resistance (Re). Slightly different free-air resonance frequency (Fs) between the two samples.<\/p>\n

 <\/p>\n

Impedance:<\/span><\/h3>\n

 <\/p>\n

\"\"<\/a><\/p>\n

\"\"<\/a><\/p>\n

(click on picture to zoom)<\/p>\n

Top:<\/strong> Mid-range sample 1 vs sample 2<\/p>\n

Bottom:<\/strong> Tweeter sample 1 vs sample 2<\/p>\n

It looks like the tweeter is using ferrofluid in the magnetic gap and it has a suppressed impedance peak at the driver resonance. The two tweeter\u2019s impedance doesn\u2019t match each other perfectly, but it shouldn\u2019t be a problem in the cross-over design.<\/p>\n

 <\/p>\n

Stay tuned for frequency and distortion measurements!<\/p>\n

 <\/p>\n

\/G\u00f6ran<\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

\u00a0Overview:   I\u2019ve used concentric (co-axial) drivers from SEAS in the past and liked them, but unfortunately SEAS hasn\u2019t refined the concept much the last 15 years and there are not generally speaking many good concentric drivers available to choose between for the DIY enthusiast. One company that certainly has improved the concentric driver concept […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-3522","post","type-post","status-publish","format-standard","hentry","category-blog"],"_links":{"self":[{"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=\/wp\/v2\/posts\/3522","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3522"}],"version-history":[{"count":33,"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=\/wp\/v2\/posts\/3522\/revisions"}],"predecessor-version":[{"id":3525,"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=\/wp\/v2\/posts\/3522\/revisions\/3525"}],"wp:attachment":[{"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3522"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3522"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.audioexcite.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3522"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}