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Showing content with the highest reputation on 12/05/2019 in all areas

  1. 4 points
    Sorry to hear of your problems. I've done a number of M-1.0t mk II opt 2 upgrades. I found a lot of ways to screw them up, but once working properly, they all produced rated power until the dummy load resistors started to melt. And if the thump problem is bad enough to scare you and your dog, consider it a symptom of some other problem, not your normal annoying (but fixable) M-1.0t thump. Here are a few suggestions. 1. If its running out of gas at high power levels, there is likely a problem in the commutator circuits. Note that the high rail commutators are triggered by a single set of components. So a failure there will cause both channels to loose the benefits of the high rail commutator. Suggest you put a scope on emitter of Q139. (I'll use examples from the positive leg of the left channel, but you might want to look at both legs of both channels.). At idle the emitter should be at the middle rail voltage. As you apply an input signal you should see some gradual switching to the high rail. Use two channels of your scope. Trigger off the output of the amp. Use the second channel to watch the emitter. No need for a load at this point, the commutators will work without it. Its also educational to look at the collector of Q127. It should sit at the low rail voltage, rising as the signal requirements dictate. 2. Check switching diodes. Shorts/open/backward diodes cause all sorts of confusing symptoms. D125 thru D132. 3. You didn't mention if the loss of power was in one or both channels. That's an important clue. Loss of power in both channels is a strong indicator of a problem in the high rail switching since the control circuits are shared between channels. 4. Horrific thumps. Put a scope on the positive and negative side of each rail of the power supply. One at a time is OK. Turn the amp on and back off. Observe the decay time. If one drops like a rock while the other just drift down, it's a strong indicator of a short somewhere. Asymmetric decay of the supply voltages is the primary cause of thumps. Look at the 12v supply while you are at it. They too should drift down together. Note that the high rail switching transistors (Q139 - Q142) used in the mk II upgrade have been known to be counterfeited. They fail at the slightest provocation. Also, you must use the TIP35C/TIP36C. Not the TIP35/TIP36. Based on my experience the use of a mag coil instead of a real transformer is not the root of the problem. Please don't be offended by my suggestions that upgrade errors may be the source of the problems. I've done a lot of mk II upgrades and about the time I felt I could do no wrong was when I committed the most bone headed errors. Oh, and I think you are in Southern Arizona somewhere. I'm in Scottsdale. If these suggestions don't work out, I would be happy to take a look at the amp. Either ship it to me or stop by when you find yourself in Scottsdale. Good luck.
  2. 3 points
    Very cool. I've seen Pink Floyd four times and the concerts are fantastic. I just bought the vinyl version on Amazon and it's getting delivered today!
  3. 3 points
    I have ready made thump-fix boards for the non-inverting if you're interested. In fact, I have all kinds of resources for that mod. The THD is not going to be ultra impressive on them - they are transfer function modified so the goal was not to make a transparent amplifier but an amp with a 'voice'. However, the THD should stay below 0.2% over the power bandwidth, improving to 0.05% near max power. If you A-weight the SNR it should easily get above 100dB, and this is what I found to be the best measure of those amps when working properly. Also, ensure your commutators are working correctly and switching as they should. If the commutators are not switching, the amp will still work fine until you reach high power where it will start clipping prematurely.
  4. 2 points
    http://www.pinkfloydz.com/watch-soon-run-like-hell-live-delicate-sound-of-thunder-2019-remix-from-the-later-years-1987-2019-box-set/ Yes? Legit? Freaking FINALLY?
  5. 2 points
    I am officially starting the Christmas season at my house with the wife gone by listening to Transiberian Orchestra’s the Lost Christmas Eve CD as is tradition here at my house......loudly but not deafening......grin
  6. 2 points
  7. 2 points
    I count myself as one of the few (perhaps sacrilegiously so) people that far prefer the post-Waters PF material to the “original” material. This set is long overdue - I just wish it were a bit cheaper, lol....
  8. 2 points
  9. 1 point
    I ordered this album a while back, after it was recommended to me as a great source for test tracks. I had played it a few times, and really enjoyed it in my truck. A few days ago, I threw a small system together (Oppo 105, C1 w/Gundry, McCormack DNA 225, and NHT 2.5i speakers, with a Velodyne DD12) to test a C1 I just finished modding for a member (BillD and Gundry). That is when my jaw hit the floor... The track Draw Your Swords absolutely BLEW ME AWAY. I do not do much listening with SH, but when I do, the Gundry mod is a must - but THIS track was unlike anything I have ever heard - truly unbelievable. Add to this the fact that the listening space I have created is FAR from ideal, makes it all the more impressive. Typing this, I find it just about impossible to put words to what I heard. I cannot recommend this album highly enough - It now owns a place in my top 5, and that is a feat.
  10. 1 point
    Funny story, I was a bartender in Calgary in the late 1980's and it was a slow afternoon. There were 3 gentlemen sitting around the horseshoe shaped bar... A 60 ish year old Biker, a 40 ish year old Oil executive, and a 20 something university student. The biker turned to the student and said have you heard the latest Tragically Hip album and the the Student said yes I love it. The Oil exec said he loved it too! After my shift I went and bought "Up to here!" Still one of my favourite albums and frankly I could put "Road Apples" or "Fully Completely on this thread as well. They are that good!
  11. 1 point
    Gave this album a good listen with SH engaged last night...Wow! Great album, really gives the system a good run. SH felt very immersive for just a 2.1 setup!
  12. 1 point
    1,200hp 2020 Corvette C8 coming soon.... http://hennesseyperformance.com/vehicles/chevrolet-2/corvette/c8/
  13. 1 point
  14. 1 point
    Opera's stable channel introduces Reborn 3. https://www.downloadcrew.com/article/30547-opera
  15. 1 point
    Came across this today! https://www.stuff.tv/features/52-essential-albums-audiophiles
  16. 1 point
    I think you were doing it right with the manual and the red wine.......grin. I have never tried to set it up. My room is not setup for it and speaker placement WILL not pass the WAF........grin
  17. 1 point
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  18. 1 point
    Thanks Andrew - I do use fuel conditioners about every 4th tank of fuel, and have since about 10k miles. I also have the “milestone” maintenance done (36k, 60k, 100k, etc...), and I’ve always done my own oil changes (Mobil synthetic). I figured the plugs would have been done at one of the milestone intervals, but it’s not indicted on my paperwork, so pretty sure they didn’t do them....
  19. 1 point
    I've always just followed the manufacturer's recommendation on plug changes..., I think that is 50k intervals, and stuck to stock plugs. I've not done plug wires. Probably more important, and I have a little experience on this one..., is that after 100K, injectors are at end-of-life. 100k of carbon build-up, or bad fuel fill-ups, take their toll. The "symptoms" of missing are similar between plugs going bad and injectors. Makes no difference if your injectors are DGI (Direct Gas Injection - injecting into the cylinders), or standard type, injecting into the intake ports, behind the valves. Although, the latter are easier to keep running clean with fuel conditioner. I suspect your truck has traditional behind the valve types. Those let the fuel conditioners "rinse" the carbon build-up off the back of the valves, while the former are affected more by ignition, carbon and heat directly from the combustion chamber. I'm at 220K on my F150, and I put fuel conditioner in every tank full of gas now, to prevent injectors from fowling..., which btw, is a HUGE expense to replace all 8 in a v8. I like the Techroline conditioner, but have also used GumOut high mileage injector cleaner and fuel conditioner. Also tried some AmsOil. I don't think it matters, as long as you are running some kind of softener/solvent to reduce the carbon and sludge build-up on your injectors. A bad injector is going to misfire and drain power just like a bad spark plug..., but a lot more expensive to fix. ... hope that's helpful, not your original question, but related to the potential symptoms that can be experienced on high-mileage vehicles. I'm looking at about $2500 to clean carbon (plus the cost of some injector replacement, another potential 6x$200) from my Audi with FSI (DGI) injectors is at 145K miles and I didn't do this fuel conditioner early enough..., Hoping I can soften enough of it to save on that expense with a few tank-fulls of conditioned gas. Cylinder 6 is still not firing..., Ugh. If not helpful, no worries, it's free advice, and worthless if not applicable.
  20. 1 point
    Further proof that it’s not all about HP... there are many systems involved - suspension, transmission, tires, and of course the driver. Much like audio, it’s about synergy. Per Road & Track, the 2020 Corvette Stingray delivered an incredible 0-60 time of 2.8 seconds (!) – which is a full 1.1 seconds faster than the C7 Stingray, according to the magazine’s tests. The transmission also clicks through through two gears in the process, at 30 and 55 mph, compared to the C7 which took first gear all the way to 51 mph. To further put things into perspective, the 490 horsepower C8 Corvette Stingray is quicker to 60 than the 650 horsepower C7 Corvette Z06
  21. 0 points
    C O O L !!! I just checked the date 3 times to make sure it's not April 1st!
  22. 0 points
  23. 0 points
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