Reply to thread

Message

<blockquote data-quote="audioholic" data-source="post: 7375673" data-attributes="member: 549629">xmax is never peak to peak, unless the company is flat out lying. xmax is defined as one-way linear. Peak to peak usually refers to physical clearance allowances, and is always expressed as two-way, not one-way. So the terms peak to peak and xmax should never be compared.No, xmech is how far it can move &#039;safely&#039;. xmech refers to how far the cone can move before stuff starts running into each other (coil bottoming out, spiders contacting the frame, etc). xmech is also suppose to be expressed in one-way terms, again assuming the company is being honest. xmax is a spec that relates to distortion output. Even if not measuring distortion levels directly to derive xmax, but instead using the loss of BL method, the only reason they measure the loss of BL is because BL distortion (caused by losing motor force as the coil leaves the gap) accounts for the vast majority of distortion a speaker produces. This is why BL curves are almost a direct relation to distortion levels when discussing motor designs.xmax is sometimes derived using the loss of BL method someone mentioned above, but its also sometimes measured with distortion thresholds as its limiting factor. Both of these methods are considered acceptable, so often times companies use which ever one makes their product appear better, and makes comparing specs from one company to another somewhat misleading, even if both companies are being relatively honest about their xmax figures (because they were derived using different methods).</blockquote>

[QUOTE="audioholic, post: 7375673, member: 549629"] xmax is never peak to peak, unless the company is flat out lying. xmax is defined as one-way linear. Peak to peak usually refers to physical clearance allowances, and is always expressed as two-way, not one-way. So the terms peak to peak and xmax should never be compared. No, xmech is how far it can move 'safely'. xmech refers to how far the cone can move before stuff starts running into each other (coil bottoming out, spiders contacting the frame, etc). xmech is also suppose to be expressed in one-way terms, again assuming the company is being honest. xmax is a spec that relates to distortion output. Even if not measuring distortion levels directly to derive xmax, but instead using the loss of BL method, the only reason they measure the loss of BL is because BL distortion (caused by losing motor force as the coil leaves the gap) accounts for the vast majority of distortion a speaker produces. This is why BL curves are almost a direct relation to distortion levels when discussing motor designs. xmax is sometimes derived using the loss of BL method someone mentioned above, but its also sometimes measured with distortion thresholds as its limiting factor. Both of these methods are considered acceptable, so often times companies use which ever one makes their product appear better, and makes comparing specs from one company to another somewhat misleading, even if both companies are being relatively honest about their xmax figures (because they were derived using different methods). [/QUOTE]

Verification