+ Reply to Thread
Results 1 to 4 of 4

Thread: Bank Holiday tinkering

  1. #1
    Join Date: Jan 2009

    Location: Essex

    Posts: 31,853
    I'm openingabottleofwine.

    Default Bank Holiday tinkering

    Normally my system remains unchanged for months and months on end, if not years, apart from occasional arm and/or cartridge swapping.

    However now that summer is approaching, I decided to install my new ‘summer’ amps, to replace the massively inefficient 25W Levinson ML-2 class-A monoblocks I normally use. These have a standing dissipation of 400W. Fine in the winter as it supplements the heating, but in the summer they are just too hot!

    The ‘summer’ amps are a pair of Quad 510 monoblock units http://quad-hifi.info/public/hfe_qua...%5b1705%5d.pdf.


    (Image: quad-hifi[.info])


    (Image: quad-hifi[.info])

    The circuit of the 510 is almost identical with that of one channel on the Quad 520 amplifier, however the speakers are not connected directly to the output transistors as in the 520 but are connected via a transformer having multiple secondary windings. The secondary windings can be connected in various series/parallel combinations, by the use of a range of plug in cards, to suit a range of speaker impedances, and more importantly provide a range of maximum out put voltages. I use Quad 57 speakers and these can be damaged by arcing if they are fed with a signal of greater than 20V rms. By choosing the correct card I can limit the output voltage to 17V rms, so the speakers are completely safe.


    (image: quad-hifi[.info])
    Interior shot of a 510, showing the output transformer, with the input transformer to the right.

    The input of the 510s is fully balanced, as it is on my Levinsons, so I can simply swap the Quads in their place. Both amplifiers are located directly behind each speaker so minimising the length of the speaker cable. Balanced line interconnects some 15m long connect the power amplifiers back to the preamp (a Levinson ML-28) which has fully balanced outputs.




    Until recently I have been using a modified Linn LINNK phono stage, but I want to make some more (minor) modifications to the LINNK, so this has now been replaced by a Levinson ML-10A preamp. Perhaps somewhat of an ‘overkill’, but it is more convenient to use that than swap in my Levinson ML-25 phono stage, as the latter uses a separate and different power supply to the ML-28. Anyway the combination of the ML-10A with the ML-28 works a treat, with the result that over the Bank Holiday I have played nothing but vinyl!





    I am very pleased with the Quad 510s so far – extended listening with time will tell me if they are as good as the Levinsons. If they are, then they could well be used permanently.
    Barry

  2. #2
    Join Date: Nov 2011

    Location: Romford

    Posts: 11,057
    I'm sorted.

    Default

    Is that a CDP-XB920E Barry?, got a mint one of those off ebay for £40, rather good

  3. #3
    Join Date: Jan 2009

    Location: Essex

    Posts: 31,853
    I'm openingabottleofwine.

    Default

    Quote Originally Posted by Roy S View Post
    Is that a CDP-XB920E Barry?, got a mint one of those off ebay for £40, rather good
    Yes it is, but I paid £60 for mine! ( )
    Barry

  4. #4
    Join Date: Nov 2011

    Location: Romford

    Posts: 11,057
    I'm sorted.

    Default

    Still a bargain

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •