Everything posted by Craig Sawyers
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The ultimate DIY? A Stax SRM-T2!
That is bloody wierd. I'd really go back to basics. Pigtail the transformer leads into a bridge rectifier taped to the bench, and measure the rectified (ac) voltage - which will tell you if there is a problem with that particular winding. Connect up a 680uF cap and again see what it measures as smoothed ac. If all is OK, then there could be an interwinding short or something else peculiar in the way the -260V is generated from 300V using a dc offset from the -500V and -60V supplies. But again I'd go back to basics - even take the Tx out, and run each winding into a bridge screwed to a piece of wood (say), then add caps and see what the actual raw dc is from each of the three windings. Then check the voltage between each of the windings - they should be isolated. Birgir - do you have a megohm meter? The windings should be electrically well isolated to a rather high voltage. If there is an interwinding short, or low resistance, it should show up using a megohm meter with the voltage set to 500V. Do your transformers have interwinding insulation barriers?
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Joe freed in Libya
That is a massive relief - that could have been really ugly in many different ways.
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The ultimate DIY? A Stax SRM-T2!
You've got that right Spritzer - tiredness (and booze) are never good partners to HV work
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Holy Crap! The New Stax Omega Looks fierce! (Stax SR-009)
I've got a BH (not SE) and a T2. Anyone want to buy me a pair of SR009's so I can tell you what they sound like?
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The ultimate DIY? A Stax SRM-T2!
Jeez - sorry to hear that. I guess I got lucky with the power supply - it just fired straight up and hasn't missed a beat since. The amp - as most of you know - was a different kettle of fish entirely. It's got to be simple though - if the cap is roasting, and the rectifier bridge is OK - then it has to be the cap. Mislabelled and electrically in backwards. If that is the case, make sure the rectifiers haven't got cooked into the bargain. Try pulling the IXYS current limiters temporarily, and isolate the transformer, bridge and capacitor.
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Choosing the right headphones
Um - how about filling in your profile so we have some idea who the hell you are?
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Happy birthday Al and Gary!
Hey guys - happy birthday!
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Happy Birthday Voltron
Al - have a great day! I'm drinking one for you right now.
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System Overhaul Thread
In the UK they were call a Flexicurve. Green in colour IIRC. Yup still available - in the UK around £5 depending on length (isn't that true of so many things). But they seem to have changed to blue.
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Hey Head-Case, what's your bandwidth like?
I want to live in Rochester! A fifth of a Gigabit per second - I had no idea that was possible. And "Sadly, most of the time I'm in my dorm on 100mbit ethernet" - well boo hoo.
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New setup help
I wondered too - but his profile says USAF, so it looks like he's at the sharp end.
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Holy Crap! The New Stax Omega Looks fierce! (Stax SR-009)
OMG. I'd better start slowly softening my wife up as a long term strategy. I've just got to have a pair of those.
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KGSS Problem
That is just great - I'll bet that kid is never picked on again! My son (many years ago) did something similar when he got fed up with being bullied and broke the kid's nose.
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Hey Head-Case, what's your bandwidth like?
I decided to run the test at work having just downloaded a 530MB CD ISO image in a bewilderingly, jaw droppingly short time.
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The ultimate DIY? A Stax SRM-T2!
Check back through this thread for modifications on the power supply. In fact I think I posted a summary of mods, to wich KG added one or two I had forgotten.
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Happy birthday, strid3r!
Have a great one
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KGSS Problem
Hear hear!
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Hey Head-Case, what's your bandwidth like?
Given the third world speed I get at home, this is what I get at my desk at Leicester University: Zoom....
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The ultimate DIY? A Stax SRM-T2!
I'm not sure how many people have now got these running. Last time a poll was done, the count was 5 out of 22 having completed and were listening. Anyone like to volunteer a current number?
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KGSS Problem
From what I've seen in the pics it is a wonder that this amp works at all!
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KGSS Problem
Looks like it for DC http://hypertextbook.com/facts/2000/JackHsu.shtml To drive 100mA through the body at 700V rail to rail of a KGSS would need a body resistance of 7k. Typical hand to hand dry skin resistance can be way below that (a k or two) - and working with high voltage usually gives "sweaty palm syndrome", which makes the hazard even worse. Hence the excellent general advice of keeping one hand in the pocket at all times while taking measurements at modest levels.
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KGSS Problem
I've just had a shudder moment. It looks to me like you are completely new to electronics - and the voltage inside any electrostatic amp is quite lethal. If you get it wrong, you can end up with many hundreds of volts with significant current capability from one hand to another - and that has a very high risk of stopping your heart. Please get someone to fix this for you - Justin already offered to do this if you sent it to him.
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There's been an explosion at the Fukushima nuclear plant...
Anybody been in touch with Stax to see if they are OK there? They aren't too far from Tokyo, so would have been shaken around pretty badly.
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Hey Head-Case, what's your bandwidth like?
Well, here we are in not-quite-in-the-21st-century England. This is 6 miles from Oxford, so hardly hicksville. The excuse is that we are more than 4km from the BT exchange.
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System Overhaul Thread
Woof woof! That sounds like a serious way of moving a large volume of air. One of my unfinished projects is a pair of dipole sub woofers to reinforce the output of my ESL57's. Used Shiva X2 drivers http://www.diycable.com/main/product_info.php?products_id=693 which have a maximum power handling of 1kW, although they do a very serious 18" or 21" driver - the Maelstrom, which can handle 1.5kW with a peak-peak excursion of 64mm (2.5"). 'Nuff to blow the windows out. Nelson Pass has done some really crazy things with bass drivers - such as the KleinHorn http://www.passdiy.com/pdf/KleinHorn.pdf and El-pipe-O http://www.passdiy.com/pdf/el-pipe-o.pdf