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mikeman400@gmail.com: Jul 03 12:06AM -0700 I have a SU3000 that works from AC power and inverter will start if you remove power, but it wont start up from battery power.   Originally I didn't have batteries to test it so I used a couple of small power supplies in series to produce the 48V it requires to operate. They were only a 1 amp supply or so but it worked.   Now with nothing plugged in, it draws a lot more amperage on startup from battery and instantly goes to overload.. When using the power supplies I originally used to start it up, it draws too much power from them and they shut down, and it doesn't get a chance to do anything but beep once and the lights blink once.     So obviously the unit is using more power than before and not just a software issue.     I am thinking it may have a bad mosfet. Cant remove them until I get my hot air station. Does this seem like a reasonable place to start troubleshooting? Maybe the mosfets were damaged from using the power supply to power the unit?   Thanks in advance for any advice

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 03 09:32AM -0400 > So obviously the unit is using more power than before and not just a software issue.   > I am thinking it may have a bad mosfet. Cant remove them until I get my hot air station. Does this seem like a reasonable place to start troubleshooting? Maybe the mosfets were damaged from using the power supply to power the unit?   > Thanks in advance for any advice   You could put an ohmmeter from drain to source and from gate to source, and see if any of them are shorted or have blown gates.   If your power supplies overshoot badly after a large load transient, you could have had a transient overvoltage. Doesn't take much energy to blow a gate.   Cheers   Phil Hobbs     -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

John Robertson <spam@flippers.com>: Jul 02 12:43PM -0700 On 2018/07/02 2:42 AM, Phil Allison wrote:   > **FYI:   > https://en.audiofanzine.com/solid-state-combo-guitar-amp/fender/PRO-185/medias/pictures/a.play,m.898605.html   That is industrial equipment, for use on stage. Not for home listening levels. The hum is quite quiet compared to the volume of the unit that it would be well within the original specs.   I have the same problem in my field. Our pinball games use industrial style art, chrome, electronics, etc. They hum, whistle, rattle and make all sorts of mechanical noises that may be a nuisance in the home, but inaudible (relatively speaking) in an arcade - where the equipment was designed to be used defines the minimum acceptable background noise levels.   Once I point that out most people are quite understanding!   John ;-#)#

jurb6006@gmail.com: Jul 02 03:59PM -0700 Actually, that is the point. If the hum is at the same level no matter how loud it is set, it is simply not suitable for home use or whatever. There is such a thing as a power soak though that can cut the output itself down which would take the hum with it.   At the music store there was a discussion about fan noise, I said something to the effect that when you are on stage they never hear that, but when you are at home listening to Mozart or some shit, that is different.   Most people do not use a 150 watt amp to practice in the kitchen. That doesn't mean they are not assholes.

tabbypurr@gmail.com: Jul 02 11:49PM -0700 > Actually, that is the point. If the hum is at the same level no matter how loud it is set, it is simply not suitable for home use or whatever. There is such a thing as a power soak though that can cut the output itself down which would take the hum with it.   > At the music store there was a discussion about fan noise, I said something to the effect that when you are on stage they never hear that, but when you are at home listening to Mozart or some shit, that is different.   > Most people do not use a 150 watt amp to practice in the kitchen. That doesn't mean they are not assholes.   It doesn't make them assholes either. It's the wrong attitude for a customer facing position.     NT

Chuck <ch@dejanews.net>: Jul 01 01:22PM -0500 On Sun, 1 Jul 2018 00:17:08 -0700 (PDT), captainvideo462009@gmail.com wrote:     >The guy that I bought the organ donor from included a large plasticized sheet with it showing all possible hookups. It also had brief explanations of all controls and their positions and there seems to be a couple of "synthesized" positions that according to this hookup sheet can apparently simulate 4 channel sound. I think that those look like "hall" and "surround". I do feel like When listening in some of these positions, perhaps I may be imagining it but the sound does seem to take on a whole new spaciousness to it.   >I recall hearing years ago when I first contacted Sansui for a service manual that the 5500 sold for over 900.00 back in it's hey day. In 1974 I was living in a small apartment over a restaurant with my cat. I wouldn't have been able to afford the carton to pack this in.   >So now after all these years I that finally own that has the capability to be used in ways that were not available to me before I don't really know what to expect from it. And so I was wondering if you might be willing to comment on that experience and maybe 4 channel analog in general. Thanks again. Lenny Lenny,   The Sansui surround system was called QS. It wasn't very successful. I noticed a few QS records on EBay including one by a Chicago folk singer Bonnie Koloc on Ovation records. I bought this album in the early 70s and, if you like poppy folk music, it would make an ideal test record to experience the QS quad experience. Chuck

Chuck <ch@dejanews.net>: Jul 02 12:17PM -0500 On Sun, 1 Jul 2018 00:17:08 -0700 (PDT), captainvideo462009@gmail.com wrote:     >The guy that I bought the organ donor from included a large plasticized sheet with it showing all possible hookups. It also had brief explanations of all controls and their positions and there seems to be a couple of "synthesized" positions that according to this hookup sheet can apparently simulate 4 channel sound. I think that those look like "hall" and "surround". I do feel like When listening in some of these positions, perhaps I may be imagining it but the sound does seem to take on a whole new spaciousness to it.   >I recall hearing years ago when I first contacted Sansui for a service manual that the 5500 sold for over 900.00 back in it's hey day. In 1974 I was living in a small apartment over a restaurant with my cat. I wouldn't have been able to afford the carton to pack this in.   >So now after all these years I that finally own that has the capability to be used in ways that were not available to me before I don't really know what to expect from it. And so I was wondering if you might be willing to comment on that experience and maybe 4 channel analog in general. Thanks again. Lenny Lenny,   The Sansui surround system was called QS. It wasn't very successful. I noticed a few QS records on EBay including one by a Chicago folk singer Bonnie Koloc on Ovation records. I bought this album in the early 70s and, if you like poppy folk music, it would make an ideal test record to experience QS quad . Chuck

Chuck <ch@dejanews.net>: Jul 02 12:18PM -0500 On Sun, 1 Jul 2018 00:17:08 -0700 (PDT), captainvideo462009@gmail.com wrote:     >The guy that I bought the organ donor from included a large plasticized sheet with it showing all possible hookups. It also had brief explanations of all controls and their positions and there seems to be a couple of "synthesized" positions that according to this hookup sheet can apparently simulate 4 channel sound. I think that those look like "hall" and "surround". I do feel like When listening in some of these positions, perhaps I may be imagining it but the sound does seem to take on a whole new spaciousness to it.   >I recall hearing years ago when I first contacted Sansui for a service manual that the 5500 sold for over 900.00 back in it's hey day. In 1974 I was living in a small apartment over a restaurant with my cat. I wouldn't have been able to afford the carton to pack this in.   >So now after all these years I that finally own that has the capability to be used in ways that were not available to me before I don't really know what to expect from it. And so I was wondering if you might be willing to comment on that experience and maybe 4 channel analog in general. Thanks again. Lenny Lenny,   The Sansui surround system was called QS. It wasn't very successful. I noticed a few QS records on EBay including one by a Chicago folk singer Bonnie Koloc on Ovation records. I bought this album in the early 70s and, if you like poppy folk music, it would make an ideal test record to experience the QS quad experience. Chuck

jurb6006@gmail.com: Jul 02 04:40PM -0700 >"The Sansui surround system was called QS."   the QS and SQ systems were pretty much the same. they cancelled the L+R out of the rear speakers but usually had a filter to not cancel the bass so you get it from all speakers, which were usually matched back them. Some may have suppressed some of the L-R in the front pair for a better sound image.   Still, it was all derived from 2 channels. they just took care to mix it right. not like Beatles - Taxman, CCR - Suzie Q, Swinging Medallion - Double Shot Of My Baby's Love. none of them work well on either system because of the way they're mixed.   They tried to sell this 90 degree phase shift as a buzzword but yes, there was but only at a certain frequency because of the high pass filter applied to the signal used to ull the L+R in the rear.   Most schemes of this type did not completely hull out the L+R in the rear to maintain some separation between LR and RR. this is where the mixing came in. they had digital delay and some of them, for directionality of the source in the front used that instead of a normal pan pot. This made it appear i the rear, if they chose, at the same level as in the front but with a certain aberration in the frequency response.   Adit was no use having 4 channel discrete unless it was recorded in 4 channel discrete. I had a 4 channel 8 track and a player and found that a Grand Funk tape had noting but mono in the front and L-R in the rear. I could have done that easily. Just a few transistors or maybe OP AMPs. In act I did more than that :   http://usr.audioasylum.com/images/7/71823/cheaps.jpg   And that is with not one active component. Some had elfakeo quad that just lifted the common from the rears, or did it with a resistor, this is just a enhancement of that. And i have done it and it sounds good. Pure 5.1 Dolby surround with no effects does exactly the same thing but hides it in an IC. Dolby does not even deserve to have their name on it. All their modes n shit, none of which I or any audiophile can stand, are a different story. Digital delay, that is not high fidelity because it does not put out the same waveforms as put into it. Adding and subtracting components still leaves the original intact, an effect like delay does not.   What other 4 channels were there ? Dynaquad comes to mind, I don't remember who did that. Marantz had SQ you could add at the bottom of their receivers, and also varimatrix that gives the user control over just how much L+R is removed from the rear channels. But no high pass. what I did was to just use it, remove not quite all of the L+R which was at about the 2:00 position on the control, and then boost the living shit out of the bass in the Rear. Any and all bass that was out of phase was highly boosted and it produced a quite pleasing effect. You should have heard Days Of Thunder on it. And all scifi with space ships, they went over your head on the screen that is where the sound went. And Days Of Thunder, when they went around the track, that is how the sound reproduced it.   Anyway, I prefer these old schemes to the ew ones. I don't like the one woofer idea, people say bass is non-directional but I CAN PROVE OTHERWISE, and those stupid balsa wood speakers, they sound like shit. The only little speakers in a subsat system i ever liked the sound of were Bose Acoustimass early system. Even they lacked a bit in the crossover point. Keep the speaker systems together. A subwoofer only augments, not supplies all the bass. Just that bottom octave. Now THAT is nearly non-directional.   Needless to say I will not be buying any of this new shit. If I have no choice, I will have no stereo. The last time that happened was when I was homeless, and that was over 4 decades ago. I do not want this new shit.

richieregel@gmail.com: Jul 02 02:10PM -0700 > the real blame lies with sites like Hulu and > YT constantlh "updating" their smart TV > apps.   Awesome. the only solution to Sony garbage .It was never perfectly good. I have one, everything claimed, and more. Sony now sucks, I was a guest DJ at an important national skating event years ago. My Sony Vio or vial, as I called was about to audio skip for no reason plenty of memory, fast processor, not even hooked to the internet, was going to skip for it's very last time. Now I wasn't going live yet but it was doing it in my earphones. now my old backup Dell was to become my main computer. Because this is when I kicked my skates with the toestop straight ahead into the screen several times after smashing it on to the floor. I than opened the outside door in my booth and kept smashing the you know what out of it. I tore out the hard drive and finished it off, then tossed the whole thing on to the nearby railroad tracks.   I hate you Sony.

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