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stereo coffee

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  1. stereo coffee

    Current of Amp

    The topic of fundamental differences of physics of Valve amps vs Solid State is covered here: http://education.lenardaudio.com/en/14_valve_amps_7.html I particularly like the highlighted section that states: "This fundamental difference of physics between Valve and Solid-state amps is rarely understood or referred to by the majority of self proclaimed audio experts, audiophile reviewers, text books, web sites or forums. Almost all explanations about differences between Valve and Solid-state amps is based on romantic subjective twaddle."
  2. With reply to the topic, No, because the music, has a flow on effect to explore better ways of hearing it. Its a unison thing. .
  3. stereo coffee

    Need help identifying these amplifier boards

    They are a bit of a mystery. I can see some clues though, at first I thought ETI 480 but the layout is not ETI480 and the reference to Quad. The board layout looks like at a latter day effort to produce a dual rail quad 303, the 303 was of course single ended. There is also suggestion that the amplifiers were part of a active loudspeaker as the inductors placed on the board are normally much smaller with other amplifiers, and are being provided on the board instead. I found a Marcus Winkler involved in the audio industry https://www.qsc.com/about-us/ Maybe look at Quads involvement with Rogers loudspeakers about 1974.
  4. stereo coffee

    Rotel amps as a pre-amp

    You just need a passive attenuator with three inputs, which from what I can see will nicely fit in with your requirements. There are many ways of doing that.
  5. Hi Felix Yes, our bodies react very strangely when blood sugar is too low or too high. Hopefully you are monitoring daily and have suitable treatment, for what is a reasonably common and well known condition. The best scenario with diabetes is to control the ups and downs with diet and physical exercise, but you probably know all of that, already.
  6. Hi By inserting a series and parallel resistor, you are forming what is called an L pad. https://en.wikipedia.org/wiki/L_pad However you are applying this to just one driver, and from what I read you have the 7.5 ohm resistor in parallel across the driver. The effect will be to reduce level in that speaker as you are trading energy the amplifier is producing to be instead dissipated in both the speaker and the resistor. As the resistor is now dissipating power which adds up to heat it needs to be of suitable wattage typical wattage would be 7-10watts Without the resistor, the amplifier was just seeing the speaker driver so would now be like turning the midrange level down Such balancing might be useful - do you prefer it that way ? -if so leave it in. 15 ohms suggests as a better figure though to match with a 6-8 ohm midrange. If you want to explore a bit more, follow the recommendations on Page 10 of this article: http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Speaker_Amp_Interaction.pdf which discusses a second zobel network at the speaker cable entry point.
  7. stereo coffee

    I think i have a problem

    Are you sure she is a woman ?
  8. stereo coffee

    Covers that are better than the original

    I recall it was played on Dave Woodhall's Rockturnal program nearly every week for over 5 years, which is where I first heard it,
  9. stereo coffee

    Covers that are better than the original

    Hendrix "All along the watchtower " is already on pages 1,3,7 and now 10 what about this one:
  10. stereo coffee

    Liability for injury if selling DIY 240v gear

    Read what is stated here, and attend to properly earthing the chassis to IEC safety mains earth. If any of that is problematic for you, suggest you have a electronics technician check your unit before selling. http://sound.whsites.net/earthing.htm
  11. stereo coffee

    The History of Stereo. Interesting Doco.

    They cleverly fail to mention Alan Blumein who was the actual inventor of stereo. https://en.wikipedia.org/wiki/Alan_Blumlein In 1931, Blumlein invented what he called "binaural sound", now known as stereophonic sound.[1] In early 1931, he and his wife were at the cinema. The sound reproduction systems of the early talkies only had a single set of speakers – the actor might be on one side of the screen, but the voice could come from the other. Blumlein declared to his wife that he had found a way to make the sound follow the actor. Blumlein explained his ideas to Isaac Shoenberg in the late summer of 1931. His earliest notes on the subject are dated 25 September 1931, and his patent had the title "Improvements in and relating to Sound-transmission, Sound-recording and Sound-reproducing Systems". The application was dated 14 December 1931, and was accepted on 14 June 1933 as UK patent number 394,325.[7] The patent covered numerous ideas in stereo, some of which are used today. Some 70 claims include: A "shuffling" circuit, which aimed to preserve the directional effect when sound from a spaced pair of microphones was reproduced via stereo loudspeakers instead of a pair of headphones The use of a coincident pair of velocity microphones with their axes at right angles to each other, which is still known as a "Blumlein Pair" Recording two channels in the single groove of a record using the two groove walls at right angles to each other and 45 degrees to the vertical A stereo disc-cutting head Using hybrid transformers to matrix between left and right signals and sum and difference signals
  12. stereo coffee

    incoming voltage

  13. stereo coffee

    incoming voltage

    Hi David Depending on where you live, (for instance farm properties) you can experience mains voltage dipping.particularly at peak times. 220 is a bit low though, as the Australian voltage standard is 240V AC. Correction Wikipedia now lists as 230v https://en.wikipedia.org/wiki/Mains_electricity_by_country Whoever wired your separate circuit, may have done so across the stove circuit which neatly explains the voltage discrepancy at dinner time. Worse is to have voltage going higher than 240v AC, whereas lower voltage is tolerable, as it is unlikely to damage any equipment Suggest you contact an licensed electrician to meter your voltage over say 48 hrs to determine when and duration of voltage dipping and at the same time check the way the separate circuit is wired.
  14. If so, owners of valve amplifiers might consider, as 16 ohms is a nice specification of resistance suiting valve amps http://education.lenardaudio.com/en/14_valve_amps_7.html that is if a small two way speaker, at that price range suits.
  15. stereo coffee

    David Gilmour Live at Pompeii option x

    I am using a Marantz UD5005 has very minimal display options but it displays it is 2 channel, so remains a bit of a mystery as to what audio option x is, but I am enjoying it.
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