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<blockquote data-quote="TJ Cornish" data-source="post: 58835" data-attributes="member: 162">Re: Subwoofer comparison SRX728 vs Vertec 4883Here are a couple screenshots from JBL&#039;s LAC:[ATTACH]150664[/ATTACH][ATTACH]150663[/ATTACH]The setup is 1 4883 on the floor with the front of the sub at the 0 line.&nbsp; The SPL plot is with a probe at 1 meter at the centerline of the sub. The difference between the two graphs is the selection of &quot;DSP SPL&quot; vs &quot;MAX SPL&quot;.From the LAC manual:When “DSP SPL” is selected, modeling results reflect VerTec V4 DSP tonal balance, including high frequency section pre-emphasis and low frequency contour characteristics. “DSP SPL” predictions for all full-range VT models are scaled to a 120 dB SPL @ 1m on-axis reference level and provide an indication of continuous, unweighted RMS SPL with approximately 10 dB of system headroom remaining. When “Max SPL” is selected, rated sensitivity and electrical power handling are used to determine the maximum peak SPL for the frequency of interest, providing an indication as to available system headroom. Neither graph shows anything anywhere close to 139dB, though based on the description above, it would seem that the &quot;MAX SPL&quot; graph should.It&#039;s too bad that they don&#039;t include SRX728s in the LAC - I know a lot of folks use them with Vertec.Edit:&nbsp; Playing with the EQ in LAC allows me to apparently get almost 160dB out of a single 4883.&nbsp; Assuming this is true and not the lack of validation of the speaker&#039;s real capability in the LAC software :roll:,&nbsp; I&#039;ll be placing an order for a single 4883 tomorrow, that will more than satisfy my low frequency needs, up to 5000 people or so.</blockquote>

[QUOTE="TJ Cornish, post: 58835, member: 162"] Re: Subwoofer comparison SRX728 vs Vertec 4883 Here are a couple screenshots from JBL's LAC: [ATTACH=CONFIG]150664.vB5-legacyid=4426[/ATTACH][ATTACH=CONFIG]150663.vB5-legacyid=4425[/ATTACH] The setup is 1 4883 on the floor with the front of the sub at the 0 line. The SPL plot is with a probe at 1 meter at the centerline of the sub. The difference between the two graphs is the selection of "DSP SPL" vs "MAX SPL". From the LAC manual: [I]When “DSP SPL” is selected, modeling results reflect VerTec V4 DSP tonal balance, including high frequency section pre-emphasis and low frequency contour characteristics. “DSP SPL” predictions for all full-range VT models are scaled to a 120 dB SPL @ 1m on-axis reference level and provide an indication of continuous, unweighted RMS SPL with approximately 10 dB of system headroom remaining. [/I] [I]When “Max SPL” is selected, rated sensitivity and electrical power handling are used to determine the maximum peak SPL for the frequency of interest, providing an indication as to available system headroom. [/I]Neither graph shows anything anywhere close to 139dB, though based on the description above, it would seem that the "MAX SPL" graph should. It's too bad that they don't include SRX728s in the LAC - I know a lot of folks use them with Vertec. Edit: Playing with the EQ in LAC allows me to apparently get almost 160dB out of a single 4883. Assuming this is true and not the lack of validation of the speaker's real capability in the LAC software :roll:, I'll be placing an order for a single 4883 tomorrow, that will more than satisfy my low frequency needs, up to 5000 people or so. [/QUOTE]

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