03-06-2025 Post does not mapped to Knowledge Tree N.B.C. Posts 11 Joined on 02-15-2025 Post #: 1 Post ID: 27999 Reply to: 27999 Nice collection of Articles https://excelsior-audio.com/Publications.html

03-06-2025 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,727 Joined on 10-12-2006 Post #: 2 Post ID: 28000 Reply to: 27999 Target SPL and Amplifier Size Thanks NBC. Nice primer on speaker/amp interface. This is probably more than most people want to know about how much power is actually required to get fairly certain measured response from speakers, also some properties required for "linear performance" from the drivers, themselves over the course of such a test. Of course, a whole lot depends on the actual topology and in-system performance of both speaker drivers (including their implementations) and real world amplifiers. Of course this does not say anything about high-demands Music Listening, but it does provide some insight into the root, inner workings of the power transfer between speakers and amps. I think it's fair to say that most drivers and amps are not designed and proofed with these simple facts in mind, let alone re-proofed with high-demands listening. https://excelsior-audio.com/Publications/Loudspeaker_Target_SPL_and_Amplifier_Size.pdf Best regards, Paul S

03-07-2025 Post does not mapped to Knowledge Tree N.B.C. Posts 11 Joined on 02-15-2025 Post #: 3 Post ID: 28001 Reply to: 28000 Mining Ancient Internet Glad to be of service Paul. www.goldsound.net/home.htm Waste of money. JBL 2245H an excellent transducer though. Paramilitary XJ-500 21st Century technology from 1986. Before the said transducer is acquired, the "trick" is finding the right horn + transducer synergy. Tranvex Music have announced their "revolutionary" new Electradyne XJ-500 15" Bass Driver with 12.5" magnet. Apart from claiming this high sensitivity unit can generate four times more power than ordinary bass speakers, they say that, "In full horn bass enclosure, tests sound pressure levels have reached a believable 145db with a power handling of 3000w (Peak)". Incredible. Phone (021) 236 9260 for details. https://www.muzines.co.uk/articles/the-news/6951 The Electradyne XJ-500 is a 15" high sensitivity bass driver with a 12.5" ferrite magnet for improved thermal cooling and increased sensitivity. Power rating is 400W continuous sine wave and 800W program. The driver has a maximum useful excursion of 9.5mm-19mm, solid cast chassis and a 3" voice coil. Frequency response is 18Hz to 1.5KHz with an average sensitivity of 100db (1W/m). Impedance is 8 and fundamental resonance is 23Hz. Recommended enclosures include full-horn loading. Also suitable for use in high power low-mid horn systems.  Tranvex Music Ltd, 89 Old Snow Hill, Birmingham B4, UK.  http://ndl.ethernet.edu.et/bitstream/123456789/4167/1/37.pdf

03-07-2025 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,727 Joined on 10-12-2006 Post #: 4 Post ID: 28002 Reply to: 28001 The Parallel Universe of SPL NBC, I am not an SPL (or statistics) freak, rather I am a Music via hi-fi freak. I don't want my Music playback compromised by limitations that spoil the Music for me. I have found plenty of drivers that sound great "to a point" that I found "limiting", just as I have found many (most...) SPL-capable drivers are limited in terms of musical expression. I actually value wide-ranging Musical Expression more than extreme rote SPL, but I have found there are times when I've had to give up something to get something else, aka compromise. Best regards, Paul S