bobovox

Wammer
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About bobovox

  • Rank
    Wammer
  • Birthday Private

Personal Info

  • Location
    SE London, Europe
  • Real Name
    Robert

Wigwam Info

  • Digital Source 1
    Arcam CD73T
  • Digital Source 2
    Pioneer N-50
  • Integrated Amp
    Arcam A90
  • My Speakers
    B&W684 + DIY
  • Trade Status
    I am not in the Hi-Fi trade

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  1. bobovox

    DLNA Control point apps for iOS

    Hi Parcelmonkey. Thanks for answering. Does Kazoo work with non-Linn renderers? I tried it and it found Minimserver OK but didn't recognise either my Pioneer or gmediaplay on the Pi and assumed that it was Linn only. Similarly, i tried the Naim app, which looked really nice but again didn't find my renderers. Kinsky works OK, a bit slow but I keep seeing messages saying I should try Kazoo - which makes me wonder if its about to be withdrawn? Will have a look at iPeng at the weekend and see how I get on.
  2. bobovox

    DLNA Control point apps for iOS

    Thanks, all, for the suggestions. Unfortunately many of the apps listed are no longer in the AppStore or I have tried and find don’t do one thing or another, eg gapless which is a deal-breaker for me. Glider seams like the best option at the moment for me - it does indeed look nice, it works with my preferred server and both renderers and has the features I want. The features that it has that I don’t want aren’t too intrusive. I haven’t tried using playlists with it yet so will see if I have the same problem. It’s not ideal, as it does some funny things like splitting albums up if the artist is not the same for all tracks and there is no way I can find of turning this “feature” off. Edit: Scratch that, after bit more playing around, Glider's NBG either; MinimServer makes it easy to find the recording you want but Glider thinks it knows better and won't play nicely. CDs are so much more convenient.
  3. bobovox

    Hi - Fi Racks

    When I went into a hifi dealer to buy an Isoblue rack, said dealer was determined to sell me another rack on the basis that it would “sound a hell of a lot better”. I explained to him that I was only buying a purpose built hifi rack in order to hide the cable salad at the back and give some semblance of visual unity to what would otherwise be a mess of different boxes and be sufficiently stiff to avoid any visible bowing long term. I left the shop with the Isoblue. My system doesn’t sound any better or any worse than when it was stacked on a sideboard. But it does look a lot neater.
  4. Which DLNA Control point apps for iOS are worth trying? Searching the AppStore turns up a very few options, so I’m wondering if I’ve missed something. Searching around on the internet, BubbleUPNP gets mentioned a lot but it’s only for Android. I’m running MinimServer (which I really like and don’t want to change) on a Synology NAS and my renderers are a Pioneer N50 and gmediarender running on a Raspberry Pi.
  5. bobovox

    Ethan Winer makes a ‘null’ cable tester

    Thanks for posting that, Keith. For anyone who hasn’t seen it, I found Ethan’s Book, “The Audio Expert” to be a very approachable introduction to practical audio science and engineering, both recording and replay.
  6. bobovox

    what serversoftware are you using

    I'm another very happy MinimServer user - It works very well as a DLNA server, especially if you have a lot of classical music in your collection, which doesn't fit the Artist / Album / Song paradigm and completely agree, Paul, about the need for better DLNA control points - particularly for desktop operating systems.
  7. bobovox

    WAF

    Richard, Thank you. The reference to doped cones was interesting to me as the first "hifi" 'speakers I owned were Royd Minstrels which featured doped paper cone mid-bass units, which I believe ran full-range (electrically) and presumably relied on the doping to produce a smooth and predictable roll-off, with an electrical cross-over / compensation network for the tweeter. I would be grateful if you would point me in the direction of any published guidance/research findings into doping techniques for speaker cones. Can you please explain what has lead you to the the conclusion that the vibration of the spider should be considered? Do Klippel laser measurements of speaker cones, or similar, confirm you view that flexure of the cone material is the predominant mechanism by which sound is emitted within the pass-band of a drive unit?
  8. bobovox

    WAF

    Richard can you explain, please. I was under the impression that drive units remained effectively pistonic (ie deflexion of the cone / dome due to flexure was negligible relative to the movement of the suspension) right up to the frequencies at which the cone starts "breaking-up" ie vibrating in a flexural mode across the cone - and drive units would be rolled-off in the cross-over well below the start of break-up. The exception being balanced mode radiators (BMR). This is an idea that I have developed through reading several textbooks on loudspeaker design (eg Louspeaker Design Cookbook by Vance Dickerson) so not something picked-up from forums. FWIW I have designed and built two pairs of DIY speakers. I am intending to show a pair of small speakers (under construction) at Kegworth.
  9. Quick update: I now have the Beocreate board, a 120W / 19V power brick and the Pi all wired up and am now listening to some music through my B&W 686s... now that I've removed the mute jumper on the Beocreate board that is It's just straight stereo pass-through to the 60W channels and the passive crossover in the speakers at the moment but the SQ is good and this system definitely going to fit in a suitcase One little detail: the power supply recommended on the Hifiberry site (MEANWELL GS120A20-P1J) I believe to be a special with a 5.5x2.1mm barrel connector. The one I got from Farnell (GS120A20-P1M) has a 5.5x2.5mm tip - the Beocreate and the Pi power up OK with this and the connection appears to be secure but I may buy an adapter to be on the safe side.
  10. As you may have seen, next year's Kegworth show is including a challenge to find the best system that will fit in a suitcase. I have decided to enter with some active DIY bookshelf speakers, using the Beocreate module from Hifiberry: https://www.hifiberry.com/beocreate It's too big to strictly be a Raspberry Pi HAT but it's basically a RPi DAC with on-board DSP and four channels of amplification. It can be used without the Pi but at this stage I'm thinking my project will use one running MPD and / or Raspotify. Perhaps I could connect a Chromecast Audio through the S/PDIF connector on the board. It's a world of possibilities. The Beocreate board is being marketed particularly as a way of turning existing passive B&O speakers active. However, the boards are quite versatile and of course can be used with any speakers. Two of the amplifiers are each rated as being 60W and the other two 30W each. No word as to what load this is onto or what level of THD this corresponds to but for a small room I am hoping it will be sufficient. The inspiration for this really comes from Scalford 2016 where Onlyconnect showed Cambridge Audio floorstanders and Quad stand-mounts powered by a Raspberry Pi DAC and amp HAT from IQ Audio and it sounded really very good. https://www.itwriting.com/blog/10071-raspberry-pi-does-audio-at-the-wigwam-hifi-show-2016.html The Beocreate documentation is a bit basic at the moment and the walk-thoughs are only strictly relevant to those taking the B&O CX50s and CX100s active. However, some extra documents were added to the Github repository at the weekend and I now think there is sufficient information there for me to have a go. I understand that further documentation is planned, so I ordered the board this afternoon. If I'm struggling to make progress into the new year I'm confident I can just use the 60W channels and knock-together a reasonable passive crossover and still take part. Drive Units I already have the drive units; these are from Scanspeak's Discovery line: Tweeter is the Scanspeak R2604/833000 ring radiator: http://www.scan-speak.dk/datasheet/pdf/r2604-833000.pdf Mid-bass is also from Scanspeak, the 12W/8524G00: http://www.scan-speak.dk/datasheet/pdf/12w-8524g00.pdf Enclosure Design & Bass Alignment I'm thinking of using 19mm thick Valchromat - somehow the unfinished "brutalist" aesthetic seams appropriate to this project. I have a supplier close to home and they can also do CNC work so will so will only need to glue the panels together. The documented designs I have found for the mid-bass all feature a cabinet of around 4 litres volume, with a port tuned to around 65Hz: http://www.troelsgravesen.dk/Discovery-12W.htm http://www.humblehomemadehifi.com/HATT-VIII.html https://www.schreinerei-thomaier.de/ase/BVSAK141-1502.pdf I've done my own modelling with the published T/S parameters and Scanspeak's own modelling spreadsheet and this looks about right. Obviously no trousers will be flapped but given the constraints of the brief I think this can be forgiven. A bit of boundary reinforcement will help I don't plan to do any room correction - the Beocreate board will take input from REW but I don't want any last minute stress and in all honesty I'd rather just be propping up the bar on Saturday night before the show. Will post again when I've finished the drawings & an FE analysis of the modes of vibration of the cabinet - for my own interest I would like to compare my modelling with some accelerometer measurements. It's an interesting challenge and am looking forward to seeing and hearing what others bring or make
  11. Thanks, Tony. I've added a line to the spreadsheet. I'd better order some wood.
  12. Are you taking DIY entries? If so, when do we need to confirm entry by? There are a few thing I need to think about / research before I know if this is viable with the project I have in mind
  13. bobovox

    Advice needed RE Royd Minstrels

    I’m not familiar with the Misson’s so couldn’t honestly compare the two. As I said above, the Minstrels have too little bass and possibly a little too much treble. Some people love them though; it is very much down to personal taste.
  14. bobovox

    Advice needed RE Royd Minstrels

    My first ever proper hifi speakers were Minstrels. The paper cones were doped with a thick layer of a gummy material; I sold mine after 15 years and the material was still moving so you will need to periodically clean the pole piece as per the instructions you have read - I think the advice originated from Joe Akroyd himself. The speakers never had much bass - although they are floor-standers the cabinet volume is only 7litres - the same size as a small standmount. They were also rather bright, with an unruly treble. The stereo imaging however was remarkable. I think £100 is about the going rate, depending on the condition of the cabinet.