{"id":135,"date":"2020-03-07T13:51:44","date_gmt":"2020-03-07T12:51:44","guid":{"rendered":"https:\/\/www.deeplake.ch\/cms\/?p=135"},"modified":"2020-03-07T13:51:44","modified_gmt":"2020-03-07T12:51:44","slug":"fixing-hum-in-logitech-z-2300-speaker-system","status":"publish","type":"post","link":"https:\/\/www.deeplake.ch\/cms\/2020\/03\/fixing-hum-in-logitech-z-2300-speaker-system\/","title":{"rendered":"Fixing hum in Logitech Z-2300 speaker system"},"content":{"rendered":"\n<p>Introduced more than 10 years ago (versions between 2003 and 2006 from what I found online), the Logitech Z-2300 provides 200 watts of total RMS Power, 2 x 40 Watts into eight ohms for the satellites and 120 watts RMS into eight ohms for the sub-woofer.<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"alignleft size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.deeplake.ch\/cms\/wp-content\/uploads\/2020\/03\/logitech_z2300_ensemble.jpg\" alt=\"Logitech Z-2300\" class=\"wp-image-140\" width=\"256\" height=\"285\"\/><figcaption>Logitech Z-2300<\/figcaption><\/figure><\/div>\n\n\n\n<p>All considered, this system was for the price a good set that provided really decent sound&#8230;. only this one was producing hum, even with inputs shorted.<\/p>\n\n\n\n<p>To find out what caused the hum, I started with a simple app (Spectroid) on my smartphone to identify the hum frequency. Spot on, it was 100 Hz. For sure the power supply capacitors needed replacement. <\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"alignright size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.deeplake.ch\/cms\/wp-content\/uploads\/2020\/03\/logitech_z2300_woofer.jpg\" alt=\"\" class=\"wp-image-141\" width=\"200\" height=\"212\"\/><figcaption>Sub-woofer<\/figcaption><\/figure><\/div>\n\n\n\n<p>Opening the box starts by removing the front grill (search for online videos) removing and disconnecting the sub-woofer. Only then are the cables long enough to remove the back plate.<\/p>\n\n\n\n<p>And then what do you find : goo, a lot of goo, glue what else sorts of mastic they had on hand to stick things in place. Connectors to back-plate, capacitors to PCB, and thermal grease (a lot, again) on heat sink and power chips. Looks like goo is too cheap, considering how much they used.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/www.deeplake.ch\/cms\/wp-content\/uploads\/2020\/03\/logitech_z2300_capacitors_after.jpg\" alt=\"\" class=\"wp-image-138\"\/><figcaption>New capacitors in place<\/figcaption><\/figure>\n\n\n\n<p>The replacement caps I selected are Elna, 10&#8217;000 uF, 35 VDC 105 \u00b0C. The fit in place nicely, and the PCB holes were large enough to accommodate the snap-in types.<\/p>\n\n\n\n<p>Re-solder all cables, re-place 31 screws and connect it to find out it works, and the hum is gone. Completely silent without input signal. Let&#8217;s call it a success, the unit is salvaged, the listener will probably be happy and all in all for 10 CHF of capacitors. Now on to clean the stack of dry, stone-hard glue pieces spread all over the lab.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Introduced more than 10 years ago (versions between 2003 and 2006 from what I found online), the Logitech Z-2300 provides 200 watts of total RMS Power, 2 x 40 Watts into eight ohms for the satellites and 120 watts RMS into eight ohms for the sub-woofer. All considered, this system [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":137,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7,17],"tags":[5,6,4],"_links":{"self":[{"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/posts\/135"}],"collection":[{"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/comments?post=135"}],"version-history":[{"count":2,"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/posts\/135\/revisions"}],"predecessor-version":[{"id":143,"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/posts\/135\/revisions\/143"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/media\/137"}],"wp:attachment":[{"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/media?parent=135"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/categories?post=135"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.deeplake.ch\/cms\/wp-json\/wp\/v2\/tags?post=135"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}