Power86 thermal test
Played around last night to bench test the Power86 and thought I would try out my new Flir One thermal camera and a recently built electronic load from FiveFish Audio.
Everything looks good so far. Rectifier heat seems to be dissipated across the sink and maintains around ~95-100F with a 1.5A load. It will be interesting to check out the thermals of the LM3886 after I get the modulus built and mounted.
Played around last night to bench test the Power86 and thought I would try out my new Flir One thermal camera and a recently built electronic load from FiveFish Audio.
Everything looks good so far. Rectifier heat seems to be dissipated across the sink and maintains around ~95-100F with a 1.5A load. It will be interesting to check out the thermals of the LM3886 after I get the modulus built and mounted.
Attachments
That electronic load looks the business - reminds me of a camping stove
Yeah, it was a fun build. It drives a pair of 1040W mosfets which are cooled by a some stock Intel coolers. I've only pushed it to 100W with my lab PSU.
Finally got round to finishing the boards today and with trepidation hooked them up to power. Test 1 in documentation is to measure voltage between ground and pin 4 then pin 8 of one of the IC's. Results 14.84v and -15.12v, well within range - phew!
Second test plug in the IC's and measure DC offset at outputs - 0.0mV! Another result so I'm good to go re fitting in case and wiring it up properly.
Tom has been amazingly helpful in private emails - for a beginner like me the support is a real benefit and makes the whole package amazing value.
Second test plug in the IC's and measure DC offset at outputs - 0.0mV! Another result so I'm good to go re fitting in case and wiring it up properly.
Tom has been amazingly helpful in private emails - for a beginner like me the support is a real benefit and makes the whole package amazing value.
+1 on the value of Tom providing one on one assistance in a very timely manner. Being able to get direct guidance from the Chief Engineer makes the prices he charges for his boards a real bargain!
Finally got mine done
Long time lurker here. This forum has been invaluable. I am an amateur for sure and if I can build this, then anyone can. I agree Tom is absolutely supportive. It performs above it's price level for sure when it comes to the sound.
Long time lurker here. This forum has been invaluable. I am an amateur for sure and if I can build this, then anyone can. I agree Tom is absolutely supportive. It performs above it's price level for sure when it comes to the sound.
Attachments
Thiele/Zobel Rev. 1.0/Rev. 2.0
Can the Rev. 2.0 values be used on Rev. 1.0 boards? I'm trying to drive a very long speaker cable.
Thanks,
George
Can the Rev. 2.0 values be used on Rev. 1.0 boards? I'm trying to drive a very long speaker cable.
Thanks,
George
Just to recap Rev 1.0 -> Rev 2.0 made three major improvements:
1) Stability when the output voltage swings near the supply rails.
2) 10 dB reduction in residual mains hum.
3) Much, much faster settling time on the DC servo while maintaining good THD performance.
Of the three improvements, you can get the stability improvements (#1 above) on the Rev. 1.0 boards with a little hacking. Toss me a line through the Contact Us form on my website (www.neurochrome.com) for the details.
Thanks,
Tom
I've finished my build
It's got about 10 hours on it now and I have to say I rather like it. It's totally silent when on and not playing music which is a good start. As to sound well, I can of course only do my best to describe the overall system sound as the Modulus-86 is accompanied by an Emotiva XSP Differential Premap, bought in anticipation of having a differential power amp to match. So these two have replaced a Ming Da Picollo integrated valve amp. Everything below is of course in my opinion.
I'm currently listening to The XX, Coexist, my current obsessive compulsive music behaviour. Lots of electronic bits on this but also intimate voices from Jamie X and Romy Madley Croft which are beautifully portrayed, hanging in front of the instruments which go deep behind them and way wider than the speakers with some effects. The sense of ambience is also excellent.
One of my favourite system test tracks is Grantchester Meadows from Pink Floyd's Ummagumma. It's not especially dynamic but it does have some characteristics that help me decide if things are going well. When they're not, whether it's cartridge set up or as in here, introducing a new component, the voices of Gilmour and Waters tend to merge into one and the twittering birds don't seem to fly back and forth as much. Similarly the bloke who comes down the stairs to splat the fly should start way back and above the left speaker. With the Modulus-86 in place all these things are spot on. So high marks for sound stage and separation.
What about what my Dad used to describe as "tone" as in it has a nice tone. The sound is crystal clear and powerful. Bass is strong but definitely a bit tighter than the Ming Da and high notes ring out with clarity and lovely harmonics where present. I've only found a few tracks where things sound a bit aggressive but then they have sounded like that with previous components - the Modulus-86 won't make bad recordings sound good!
I've not tried my vinyl set up yet, it's easier to swap tracks on the Vortexbox. This is linked via a Meridian Director DAC into the Emotiva pre then to the Modulus-86 and out to a pair of Alpair 10p speakers in Frugelhorn XL cabinets. Room size is about 23' by 14'. There's plenty of power to raise sound levels way beyond what my old ears want but when I have gone loud things do not harden up.
Finally I have got to give a big thank you to Tom Christiansen who is a total star. As I've said, I'm a total novice in amp building and he answered my string of very basic questions promptly and with clear, non-patronising answers. Thanks also to the guys here on DIY Audio who gave encouragement and guidance during this build. I made some ****-ups such that when I first powered up I only had one channel. Tom took me through a host of tests until we tracked down the offending dry joint - OK, maybe more than one! I decided to do this particular kit because if I was going to build something it had to be worth putting in my main system. I've learnt tons doing this and developed lots of new skills - oh and the amp is staying.
It's got about 10 hours on it now and I have to say I rather like it.
It's totally silent when on and not playing music which is a good start. As to sound well, I can of course only do my best to describe the overall system sound as the Modulus-86 is accompanied by an Emotiva XSP Differential Premap, bought in anticipation of having a differential power amp to match. So these two have replaced a Ming Da Picollo integrated valve amp. Everything below is of course in my opinion.I'm currently listening to The XX, Coexist, my current obsessive compulsive music behaviour. Lots of electronic bits on this but also intimate voices from Jamie X and Romy Madley Croft which are beautifully portrayed, hanging in front of the instruments which go deep behind them and way wider than the speakers with some effects. The sense of ambience is also excellent.
One of my favourite system test tracks is Grantchester Meadows from Pink Floyd's Ummagumma. It's not especially dynamic but it does have some characteristics that help me decide if things are going well. When they're not, whether it's cartridge set up or as in here, introducing a new component, the voices of Gilmour and Waters tend to merge into one and the twittering birds don't seem to fly back and forth as much. Similarly the bloke who comes down the stairs to splat the fly should start way back and above the left speaker. With the Modulus-86 in place all these things are spot on. So high marks for sound stage and separation.
What about what my Dad used to describe as "tone" as in it has a nice tone. The sound is crystal clear and powerful. Bass is strong but definitely a bit tighter than the Ming Da and high notes ring out with clarity and lovely harmonics where present. I've only found a few tracks where things sound a bit aggressive but then they have sounded like that with previous components - the Modulus-86 won't make bad recordings sound good!
I've not tried my vinyl set up yet, it's easier to swap tracks on the Vortexbox. This is linked via a Meridian Director DAC into the Emotiva pre then to the Modulus-86 and out to a pair of Alpair 10p speakers in Frugelhorn XL cabinets. Room size is about 23' by 14'. There's plenty of power to raise sound levels way beyond what my old ears want but when I have gone loud things do not harden up.
Finally I have got to give a big thank you to Tom Christiansen who is a total star. As I've said, I'm a total novice in amp building and he answered my string of very basic questions promptly and with clear, non-patronising answers. Thanks also to the guys here on DIY Audio who gave encouragement and guidance during this build. I made some ****-ups such that when I first powered up I only had one channel. Tom took me through a host of tests until we tracked down the offending dry joint - OK, maybe more than one! I decided to do this particular kit because if I was going to build something it had to be worth putting in my main system. I've learnt tons doing this and developed lots of new skills - oh and the amp is staying.
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Thanks Kevin. I got the case from ebay seller Doukmall - Chinese but they do ship some stuff over to UK and EU so I got mine from UK. Last time I looked they were sold out in China but maybe they'll have a US warehouse?
Cheers, Ian
http://www.ebay.co.uk/itm/251548947138
Cheers, Ian
http://www.ebay.co.uk/itm/251548947138
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You're very welcome. Congratulations on a build well done. I'm glad you like the amp. Thank you for your kind words. It's success stories like this that keep me going.
Thanks,
Tom