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Thread ID: 145518	2017-11-22 03:35:00	Panasonic stereo - question about speakers	BBCmicro (15761)	PC World Chat

Post ID	Timestamp	Content	User
1442376	2017-11-23 04:01:00	...........just imagine little Jimmy comes along and turns the volume knob right up as toddlers are wont to do, just as the cannons are firing in the 1812 overture, get real smoke effects for free :clap	Terry Porritt (14)
1442377	2017-11-23 04:06:00	Terry and Dugimodo, weren't these types of problem the source of discussions in the 1950s, '60s and even into the '70s. I would have thought it was all sorted out by now. By the way I still have a Quad 33/303 that I would not part with. But I always wanted a pair of electrostatic speakers to go with it. Never happened.	Richard (739)
1442378	2017-11-23 04:20:00	Sorted? sure. On a quality stand alone amplifier there is usually some sort of protection and limiting circuitry and often an impedance selector. But when you sell something as a package you can save money by designing for a known speaker load so there's no guarantee it won't explode if you connect a different speaker to it. There's really no danger with higher impedance though, as already mentioned it's connecting lower impedance speakers than is potentially damaging. Same deal with connecting speakers in parallel, it increases the potential load on the amplifier. Without knowing anything about the particular amplifier design it's best to avoid lower impedance speakers unless the manual (remember those) says it's ok or if you can keep Terrys little Jimmy away just avoiding the top couple of volume steps (risky).	dugimodo (138)
1442379	2017-11-23 21:25:00	Better amps often have an impedance selector or a matching circuit Dont thinks Ive ever seen that on Solid State amps. :) Was important on valve amps for sure . Protection circuitry, not necessarily that common of some of the high end amps, perhaps its seen as something that may effect sound quality (even though it shouldn't) Way back, my Inefficient Kef speakers at party volumes were more of a strain on my amp than 4ohm speakers might have been . More efficient speakers could have easily doubled loudness for same power (ie loudness as heard by humans ) Getting way off tangent here. At non-party vol levels , 4 or 8 ohm wont matter that much on most modern home stereos. chances are , if cranked, the tweeters may blow before the amp anyway.	1101 (13337)
1442380	2017-11-24 03:44:00	I can confirm that my 8 ohm speakers from the 1970s work fine, with just a small volume control increase from about 12 to about 16 on a scale where the max is 50. I just now looked up the power spec of my 8 ohm speakers - only 20W. Their manual says 3.6W provides 95dB at 1m at 400Hz The Panasonic system is rated at 300W RMS, presumably 150W per channel. I wouldn't be surprised if they are relying on the leads absorbing some of that - the wires are not vey thick The Panasonic system (incl the speakers) cost $250. For that you get - 300W RMS (a surprising amount of power for such a small-and-cheap system) - FM radio (better reception than my old system, a $900 Pioneer) - Bluetooth (which worked straight off with my phone) - aux in, with a software selectable gain switch (of about 8 dB?) - 10 or so equaliser presets - a single user-adjust preset (Bass -4 to +4, Treble -4 to +4, also a Mid freq setting). This takes the place of whatever provided preset has been paired - Digital Bass, which I think is independent of the presets (adjustable 0 to 6 I think) - single blue light surrounding the volume knob. This can be turned off - speakers not as bad as I was expecting Cons: - useless manual - remote could be more intuitive - BT lacking in volume (I seem to have this problem often) - no wifi - no optical-in - speakers cheap-looking with shiny black plastic (But actually they are purely functional. They have horn flares over speakers and port) - has a clock but only displayed on demand. It's for setting a sleep timer I think. Display normally sits on 'aux' or '92.50' - would have liked another aux-in. One for TV-in, the other for Wifi music. (I have a Wifi music receiver which streams from my PC, including internet radio). With just the one aux-in, I have a mechanical AV switcher from the days of VHS to select various sources. But it is not ideal having to physically walk to the equipment. If I leave the aux-in switched to TV, a button on the remote switches between FM Radio and TV, which is the main thing	BBCmicro (15761)
1442381	2017-11-24 08:05:00	I forgot to mention the Panasonic SC-UX100 has a CD player (standard CD or mp3, CD-R/RW) and also a USB2 port. It's on the front, recessed about 20mm (mp3 FAT32) For mp3 playback, the folder is the Album and file is the Track. Display A001T001 for example. It says the display is 32 characters and supports ID3 1.0, 1.1, 2.3	BBCmicro (15761)
1442382	2017-11-24 19:06:00	For BT audio are you turning the volume on the phone all the way up? Silly question maybe but I find the BT audio in my car is often very quiet because I've turned the phone down while using it elsewhere but with the phone at max the levels are about the same as other sources, radio, cd, etc.	dugimodo (138)
1442383	2017-11-25 00:12:00	Dont thinks Ive ever seen that on Solid State amps. :) Was important on valve amps for sure . Protection circuitry, not necessarily that common of some of the high end amps, perhaps its seen as something that may effect sound quality (even though it shouldn't) Way back, my Inefficient Kef speakers at party volumes were more of a strain on my amp than 4ohm speakers might have been . More efficient speakers could have easily doubled loudness for same power (ie loudness as heard by humans ) Getting way off tangent here. At non-party vol levels , 4 or 8 ohm wont matter that much on most modern home stereos. chances are , if cranked, the tweeters may blow before the amp anyway. i've seen impedance selector on a few amps. very rare tho. protection circuits are fairly common. often just temp overloads. makes no difference to sound as its separate circuit. lower efficient speaker will require more amps to get the same sound volume. the trade off is they are generally better sounding speakers. generally the more efficient a speaker is, the worse the quality is. the more you crank the amp up, the more distortion it creates and thats often is what kills speakers.	tweak'e (69)
1442384	2017-11-25 00:15:00	I can confirm that my 8 ohm speakers from the 1970s work fine, with just a small volume control increase from about 12 to about 16 on a scale where the max is 50. I just now looked up the power spec of my 8 ohm speakers - only 20W. Their manual says 3.6W provides 95dB at 1m at 400Hz The Panasonic system is rated at 300W RMS, presumably 150W per channel. I wouldn't be surprised if they are relying on the leads absorbing some of that - the wires are not vey thick The Panasonic system (incl the speakers) cost $250. For that you get - 300W RMS (a surprising amount of power for such a small-and-cheap system) it will not be a true 300w rms. find the distortion spec its rated to and you will find that its really high. edit: found it its "150 W per channel (4 ȍ), 1 kHz, 30% THD" which is absolute crap. they used be rated at 10% which is crap. normal spec is something like 1% or 0.1% can't quite remember which. 30% is just a joke. if you rated it at the normal distortion spec you will get something like 50w rms output.	tweak'e (69)
1442385	2017-11-26 18:49:00	For BT audio are you turning the volume on the phone all the way up? Silly question maybe but I find the BT audio in my car is often very quiet because I've turned the phone down while using it elsewhere but with the phone at max the levels are about the same as other sources, radio, cd, etc. Yes that was the problem :) Thanks Too many volume controls in series - I missed the phone itself I hope the 30% distortion is in the speakers not the amplifier tweak'e although, with the low volumes I listen to these days it mightn't matter	BBCmicro (15761)
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