Jump to content

Leaderboard


Popular Content

Showing content with the highest reputation on 02/03/17 in all areas

  1. 4 points
    Amplifier #2: Problems noted: * Jamicon caps. AGAIN! * Rail Voltage was 76 Volts DC (with a precise 240VAC supplied) * Capacitor Voltage rating was 80 Volts DC (minimal overhead). * Capacitor temperature rating was 85 degrees C. * Horizontal heat sink fins. * Leaking capacitor gunk™ damaged the PCB AND resulted in the destruction of one output stage. Solutions: * Fit decent quality capacitors. In this case, Nichicons. * Fit higher Voltage rated caps. In this case, 100 Volts DC. * Fit higher temperature rated caps. In this case, 105 degrees C rated. Photos: A_1) Two visibly faulty caps. A_2) Measurement of a visibly OK cap. Note the ESR figure. A_3) Damage to the PCB and output stage from leaking capacitor gunk™. A_4) Measurement of the replacement caps. Note the ESR figure. Moral: Be very wary of Jamicon caps. Be very wary of caps that are fitted to hot running products, where proper attention to cooling of those caps is ignored. Be very wary of caps that are operated close to their maximum Voltage ratings.
  2. 4 points
    Jamicon electrolytic caps have been mentioned a few times in this forum. In the past few months, I've had two different amplifiers, from the same manufacturer land on my bench. Both use/d Jamicon caps. Now, the caps were bad enough, but the problems were significantly compounded by other factors. First, we start with amplifier #1: Problems noted: * Jamicon caps are not in the top tier of cap manufacturers. They are decidedly below average in my experience. * Rail Voltage was 62 Volts DC (with a precise 240VAC supplied via a Variac™). * Rated capacitor Voltage was 63 Volts DC. * Capacitor temperature rating was 85 degrees C. * Heat sinking consists of horizontal fins, rather than vertical. Thus, convection cooling was almost non-existent and radiation was the only method available. Heat is thus radiated inwards as well as out. * Leaking capacitor gunk™ (the trade marked term for the fluid inside electrolytic caps) has damaged the printed circuit board (PCB). Solutions: * Fit decent quality caps. In this case, Nichicons * Fit higher Voltage caps. In this case, 80 Volts. * It would have been preferable to fit 105 degree C caps, but these were not available at the time of service. * Fit larger caps, for an improvement in sound quality. Photos: 1) 8 main filter caps. 4 are completely destroyed. 2) Leaked gunk™ on the PCB. 3) Measurements performed on one of the caps that appeared to be OK. Note the ESR value. 4) Measurement of a good quality cap. Note the ESR value. 5) New caps fitted. 6) New caps fitted. Next up, amplifier #2.
  3. 3 points
    Just thought I'd put up my amplifier build. This amp was up and running around 6 months ago, but I've just put the final touch in it. Replaced my 1000va Nuvotem transformer to a Torroidy "Supreme audio grade" transformer. I'll post some pics of the process here. I have called this the "Zeus Audio - Simamp". I had some cast silver "Zeus Audio" name plates made for my Tsunami speakers so I thought to carry on the tradition with the other projects I build. Original speaker Logo. 3d printed wax, then cast in silver. Expensive logo. I started by reading the Bob Cordell book "Designing Audio Power Amplifiers". I produced a schematic using the best bits of the book. Decided to use a nice symetrical layout. Not because it sounds better, but because of my psychological tendancies. The amplifier was also tsimulated using the same "Ltspice" program learned by reading the book..and google. Voltage out (green). Power across 8ohm load (blue) simulated power acros 8ohm load Current though 8ohm load at max power before clipping. FFT plot @ max power 1000hz THD @max power 1000hz To be continued Cheers Simon
  4. 3 points
    You always know you have a good sound engineer when they walk from behind the glass into the recording room in the practice sessions to make sure what they are recording is like it really is. Your selection of an accurate audio system should follow the same ethos. But.........If you don't have walk through access to your source live? "Difficult it is" my Yoda quote for today. Answer see as much live acoustic music as you can. Especially those that are broadcast live to air or you can obtain quality live recordings of. The latter being the better. I know many may disagree but this worked for me. Buy the best headphones you can. For 10 years I listened through Stax headphones and a Bi polar class A pre that ran so hot you could fry eggs with it. All in glorious analog with Nakamichi tape deck & tricked out Ariston TT After that nearly every speaker I listened to sounded like minced puke. The most notable exceptions being a very high end Accoustat with JBl 15 inch bass drivers. A Klipschorn. Some custom 15 inch Tannoy royals with a cork front baffle. Quadral Titans and lastly Apogee mini grands. I was forever altered with French Champagne taste & little disposable income. I finally found a compromise I could endure and afford. Teac CD transport. Onkyo Digital 8800 120w amp with a really awesome internal discrete D/A that took up nearly half the amps internal real estate. Some Krix Di Apolito design 10 in 2 ways with Morel drivers in a sealed cab who's model name escapes me. Sweet sounding with warm enveloping bass.That system punched way above it's price point. I also got the lot at a stupid bargain clearance price. I was finally on my way to acceptable audio performance in the home environment. There is a revolution in audio I see evolving. There is the established large audio manufacturers fighting to stay relevant with the old and inefficient marketing models of manufacturer to distributor to retailer to customer. Then there is the small cottage industry headed by passionate mavericks who produce hand made audio that are not only high end but truly works of art.The likes of Volti Audio, The sound of the wood, Weston Acoustics. Once Analog These use the internet to market direct to customers. Saving a lot of middlemen but on the other hand making local auditioning difficult if not impossible. Often requiring a prospective customer especially os to make an expensive leap of faith. There will always be a place for the oldschool marketing model in the realm of home theatre & digital technolgies that requre mass manufacture to make them cost effective. In closing Listen to as much live music as you can learn as much as you can and audition as much as you can. Remember sharks patrol these waters. There are fewer of them but that makes em more cunning leaner and hungrier. Stay smart and stay safe & enjoy the music.
  5. 3 points
    It should sound like the band,in all it's glory, is clearly playing in your room.
  6. 2 points
    I just figured out the best thing about listening to Vinyl records . It's not the great sound with a little bit of crackle and pop , It's not the fact that i can listen to all the records I bought in the 70's and 80's . It's that they last about 20 mins which is about the same time it takes to polish off a stubby , so I only have to get up once ,
  7. 2 points
    I can see the influence of GBS. Jim would be proud.
  8. 2 points
    I am not going to de-rail this post. I have made my suggestions.
  9. 2 points
    rantan the CD-S7DAC obviously has digital inputs with the extra DAC. Also has XLR outs which the CD-S7 doesn't. Apart from those differences assume their basically the same. My mate has the CD-S7 so could do a comparison one day to confirm. I've just put the CD-S7DAC into one of my main systems and will do a comparo with the CD-S8 hopefully this evening. I did a quick one a fair while back and preferred the CD-S8 by a fair margin at the time. Will be interesting.
  10. 2 points
    Item: JBL 4365 Three Way Floor Type Studio Monitor Pair - Showroom Display Stock - As New Price: $12,990 Location: KLAPP AV, 72-74 Chapel Street, Windsor VIC 3181 Phone: Call us on 1300 668 398 Item Condition: Showroom Display Stock - As New Payment Method: Cash, Bank Transfer, Paypal, Credit/Debit Cards Extra Info: KLAPP AV Showroom Display Stock Perfect "As-New" condition Full warranty provided Colour: Walnut, Grille Color Monitor Blue Three Way Floor Type Studio Monitors More information here: http://klappav.com.au/products/4365 Pictures:
  11. 2 points
    Item: Sonus Faber Amati Futura Floor Standing Speakers - Showroom Display Stock - As New Location: KLAPP AV, 72-74 Chapel Street, Windsor VIC 3181 Price: $26,999 Item Condition: Showroom Display Stock - As New Payment Method: Cash, Bank Transfer, Paypal, Credit/Debit Cards Extra Info: KLAPP AV Showroom Display Stock Perfect "As-New" condition Full warranty provided Colour: Red Violin 3.5-way Vented Floor Standing Speakers More information here: http://klappav.com.au/products/amati-futura-floor-standing-speakers-floor-stock Pictures:
  12. 2 points
    Thanks Anthony I would like to have added up the hours I spent in planning, reading, sitting on the computer designing, buying and building, testing, finding mistakes and building again. I think it would have shocked me as well. As you know half the fun is in the learning in the process and the other half is the sastisfaction at the end of it. This is "Deep end DIY"
  13. 2 points
    I agree, but I see 20 Metres of speaker cable as a potentially VERY serious problem, if low inductance/low resistance products are not chosen. That said, I agree that other aspects of the system could possibly be worthy of examination. However, first things first: And that means speaker cables MUST be addressed.
  14. 2 points
    I love an over the top build Simon. Nice stuff! I wonder how many people look at those photos and have a comprehension of just how much planning and effort actually goes into building from scratch like that. Awesome work...and your own circuit to boot...that's hardcore DIY right there.
  15. 1 point
    Pretty chuffed with the new wheels. Not high end, I know, but perfect for my arthritic hands. The disc brakes are much easier on them. The 27 speed Derailleurs are very handy around here (very hilly). A fine replacement for my 20 year old, chrome-moly frame, Shogun Trail Breaker. http://www.breezerbikes.com/bikes/details/liberty-3r
  16. 1 point
    Art Blakey And The Jazz Messengers!!!!!Impulse!Art Blakey!Jazz Messengers!!!!!! & James Carter Conversin' With The Elders.
  17. 1 point
    ii''s suggest that with that amp, you can go with speakers that are on the brighter side of neutral. i.e if a pair of speakers were described as 'too bright' with a modern amp they may sound 'just right' with your vintage Sansui. The advice that @gemini07 gave is sound though, no need to rush into anything. Get to know your new friend and then plan your next move
  18. 1 point
    Haha...it's funny what we can justify at times...like a $6k cnc to save $4k of cutting ...I sorta wish I'd done the same thing...could do some really fancy things with these amps.
  19. 1 point
    Shape the edges with a stanley knife and you have overly large shuriken that can prove deadly in the right hands or indeed neck.
  20. 1 point
  21. 1 point
    Here is a little video showing how well behaved the NX050 amplifier is. Have a look at my Holton Audio Facebook page to see video https://www.facebook.com/DIYHoltonAudio/
  22. 1 point
    Here is the latest main board update for the NX050 desktop power amplifier. Anodised front panel has been delayed but should become available in the next couple of weeks. The latest version now has an updated power controller, more conventional fusing regime and I have added some solid state relays to more precisely control the loudspeaker output and provide lightning fast disconnection of the loudspeaker after turn off. This latest update also has the option of 12v trigger turn on turn off input. Oh and this one now has Dual Die Mosfets for double the current output capable, really does make quite a difference to the perceived power delivery. I will bring this amp with me to the next GTG in Hobart around Easter time.
  23. 1 point
    *** Make an Offer *** Item: Sonus Faber Elipsa Red Special Edition Floor Standing Speaker Pair - Showroom Display Stock - As New Location: KLAPP AV, 72-74 Chapel Street, Windsor VIC 3181 RRP: $ 23,995 Item Condition: Showroom Display Stock - As New Payment Method: Cash, Bank Transfer, Paypal, Credit/Debit Cards Extra Info: KLAPP AV Showroom Display Stock Perfect "As-New" condition Full warranty provided Colour: Red with medium gloss ecologically sensitive lacquer 3-way Vented Floorstanding Loudspeakers More information here: http://klappav.com.au/products/elipsa-red Pictures:
  24. 1 point
    I got this at a great price from CCMusic last week. It's sitting at home taunting me to make some time to sit down with it properly.
  25. 1 point
    Absolutely agree 100% - sharing such information is very useful, especially for those who have a technical interest in such things.
  26. 1 point
    Yeah I know, I'm pretty wild
  27. 1 point
    Yeah, I'll chuck them one day. For the time being, I use them to shame the manufacturer and supplier. FWIW: This batch of caps exhibited a 30% failure rate. Despite having used thousands of Panasonics in the intervening period, I've experienced perhaps one or two failures. Way, WAY less than 1%.
  28. 1 point
    It's not just Jamicon that do this I've seen other brands such as Nichicon and Elna do the same, and they were operating well under the operating voltage of what the specs are. Don't have photos because I saw these almost over a decade ago when I was working for 2 different organisations. I had a Rubycon in a Sharp copier blow up in my face as I was getting a voltage reading and stunk the whole warehouse out. I see it less now because the manufacturer I work for now have some very reliable Electronics and we rarely have any issues. The other onus is on the brand of products that go on the cheap, and Roger Sanders is no different. He was using 100V / 10.000uf Jamicon caps 85C in a Sanders Magtech early in the peace and it's caused him enormous grief. He is now using 120V 8200uf 85C in all his current Magtech and I'm on the constant watch for leaks on the one I have, I'm just lucky that he provides a lifetime warranty and in one case on a different thread he didn't asked for proof of purchase all questioned how the amplifier was used and send out 8X 120V 8200uf and 2 amplifier modules brand new to a member here @realysm42 who didn't have any tools to fit the caps. So what's your problem @Zaphod Beeblebrox Jamicon caps are the best, they pay your bills!
  29. 1 point
    If you are saying it's no V8 then fair enough. My 1.2t matches the torque of a Toyota 2.4l naturally aspirated engine at 1/2 the revs. That is more than capable of towing a modest trailer or even a caravan ( our family caravan hauler in the 80s was a 2.0 litre sigma and it was " adequate"). There is a lot of ignorance about small turbo engines but car buyers are notoriously conservative, particularly in Australia.
  30. 1 point
    Hi Michael these are the editions I have. I purchased them via Discogs it seems and not Amazon. https://www.discogs.com/Various-Whiplash-Original-Motion-Picture-Soundtrack/release/7168841 https://www.discogs.com/Various-Whiplash-Original-Motion-Picture-Soundtrack/release/7168841 as mentioned, I've scratch the red version taking of the top plate of the Vinyl Flat. It's just the last song but still not happy about my clumsiness. @Hensa Greg, this is the red version you have as well.
  31. 1 point
    I had a friend over a few months ago and cranked Clapton's "Cocaine"...... "Ooo! its been a while since I had a pair of speakers pick me up and throw me against the back wall" was His comment... Tase.
  32. 1 point
    Just mark your item as SOLD (top right corner) please. No need to edit the Title.
  33. 1 point
  34. 1 point
    ...story continue, couldn't get it to work so went through the MSI forum and found there's a bug within bios and clear cmos doesn't work unless one pull out the battery, so done that couple of times and finally got it to boot...but early today I had some brainfart and was thinking about power supply, there's no way I can supply it with only one 8A rail, simply not enough juice, there aren't any enough powerful PSUs on the market unless I would be willing to stretch +$500 for dual/triple rail and even than we are talking about LT108X based PSUs with ripple of 10-30mV, I could get 2-3 from Kim with 100uV but that's $250 each and hell of a lot space required, so was further searching on the web and found low ripple PC SMPS (5-10 mV) with 550W output, here are some measurements of the corsair RM550x, anyway I had to buy some as I had continue with remaining install and tweaks, will measure it's noise at the USB output and report my findings, until I get further funding for better one (from Kim) it'll have to stay as is
  35. 1 point
    Midnight Oil - Breathe. original Euro pressing. probably a bit of an underrated Oil's album as it was quite different sounding to what went before and after. Almost introspective and laid back. One of those albums that does get better with more play time. The reissue would be well served to be spread over 3 sides.
  36. 1 point
    Hi there, We should all be listening to live music - our audio systems should only be a reminder of the real thing! But having said that I have to admit to a certain fondness for:- Beethoven's 5 Cabernet concertos often followed by his colossal 9th Shiraz ! Boots.
  37. 1 point
    There is s pair in the Perth B&O store. I popped in on my last break and had a listen. These puppies are impressive, but, Hotel California!
  38. 1 point
    If you enjoy jazzy vocals, these two have substantial and luscious bass and beats. Jose James No beginning no end Gregory Porter Take me to the alley
  39. 1 point
    managed to pick up a m5 body with the $300 cash back happening definitely a mini me thing going ..with the M5 next to the 5D4 a quick shot to check all works ! using the sigma art 35mm, I am very impressed with so far in use. A lot of thought has gone into its design. VERY well made thing and just works and so well. Very pleased ! things have come a LONG way from the previous eos m series and have owned both the m and m3 prior !
  40. 1 point
    I know that this is a old post but! Volvo, safe and boring. Not this one absolutely not boring and I don't think it's safe either. Figures vary a bit but roughly 800 bhp and 1000Nm, now owned by Guy Martin in England, he calls it the fastest car in GB. Had one like it, just 730 hp less and boring.
  41. 1 point
    Not organ but Bohren & Der Club of Gore - Black Earth (doom jazz not metal) for some ground shaking bass goodness
  42. 1 point
    Did you like the 150 Lashes? I don't tip it down the sink or anything but I find it a bit 'meh' but yes, would be nice after a hot Daybro day, no doubt! The Bro likes it. Where do you get all your beers? Those Fuller ones look interesting. Our local Dans is slowly morphing into just another place to cater to mouth breathers, haha.
  43. 1 point
    I downloaded the REW user manual and my god the lack of continuity is mind boggling. My Umik USB mike sits in the draw waiting to be used. When I get a spare 10 days, six jars of coffee and a computer degree I might try again.Sent from my SM-T113 using Tapatalk
This leaderboard is set to Melbourne/GMT+11:00
×
×
  • Create New...