ces 2006
I have taken pictures, see this thread
jleaman said:CES DAMNI* i want to go some day.. Some one better take pic's
I have taken pictures, see this thread
snubbers
Hi Nixie,
Thank you for the idee's.
Option 1 is not easy to do for this moment. In fact you should use a potted transformer.
Option 2 is no option because i already build the amps. It's no point of discussion that a seperate (raw)power supply is better,
but practical ...
Option 3 is "easy" to do. I read the snubber article of Jim Hagerman with great interest and i will try it.
B.t.w. i use two full wave bridges with HFA25PB60(ultrafast soft recovery) rectifiers. Some guy's use a rc snubber of 100R+100N parallel.
Maybe that's a good start?
Hi Nixie,
Thank you for the idee's.
Option 1 is not easy to do for this moment. In fact you should use a potted transformer.
Option 2 is no option because i already build the amps. It's no point of discussion that a seperate (raw)power supply is better,
but practical ...
Option 3 is "easy" to do. I read the snubber article of Jim Hagerman with great interest and i will try it.
B.t.w. i use two full wave bridges with HFA25PB60(ultrafast soft recovery) rectifiers. Some guy's use a rc snubber of 100R+100N parallel.
Maybe that's a good start?
Attachments
snubbers
Hi Guys
Theese are really exelent.
http://www.evoxrifa.com/cap_catalog/rc_units/gen_info_rc.pdf
http://www.evoxrifa.com/europe/specs_rc_caps.htm
Hi Guys
Theese are really exelent.
http://www.evoxrifa.com/cap_catalog/rc_units/gen_info_rc.pdf
http://www.evoxrifa.com/europe/specs_rc_caps.htm
Snubbers+pictures
Hi Hugo,
The pictures were already posted in a other thread. In fact this is a better place.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=70074
The evox rifa caps shoud be excellent but this weekend i will try something from my "junk box". If there is any result i order rifa's.
Gr.
Johan.
Hi Hugo,
The pictures were already posted in a other thread. In fact this is a better place.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=70074
The evox rifa caps shoud be excellent but this weekend i will try something from my "junk box". If there is any result i order rifa's.
Gr.
Johan.
joho, don't put the snubbers around the rectifiers. Read the actual link I posted on the previous page; an RC or RC+C snubber should be across the secondary. Also, it's best to use a scope to find the right part values, unless you know the actual values of transformer's parasitic reactances and can use the formulas to calculate them.
~60 Watt Aleph BOM
Regards Gentlemen,
I am a new DIYer and farily new to posting as well. Hope I am posting in the right place...
I have been searching for a BOM and advice for a 60 watt pair of Aleph X.
I think 100 watts is too hot and too much ( I live in Miami, FL ) however, I think "Grey's" 40 watt is slightly under powered.
The BOM's I have seen are from several years back and just wondering if there have been any updates or known tweaks in the mean time.
Pretty much looking to "copy cat" as I don't have too much experience nor too much time to experiment.
Thanks in advance,
Luke
BTW: I have been totally blown away by Nelson Pass. Not only his elegant and amazing designs, but his willingness to give away and share his knowledge. His white papers are truly amazing and humorous at the same time.
After reading the "EL Pipe-o" white paper ( they smoked 26" 300 watt woofers ), and seeing his Rolling Stones pix ( on this site ) I *do* hope that he is protecting his hearing!
Regards Gentlemen,
I am a new DIYer and farily new to posting as well. Hope I am posting in the right place...
I have been searching for a BOM and advice for a 60 watt pair of Aleph X.
I think 100 watts is too hot and too much ( I live in Miami, FL ) however, I think "Grey's" 40 watt is slightly under powered.
The BOM's I have seen are from several years back and just wondering if there have been any updates or known tweaks in the mean time.
Pretty much looking to "copy cat" as I don't have too much experience nor too much time to experiment.
Thanks in advance,
Luke
BTW: I have been totally blown away by Nelson Pass. Not only his elegant and amazing designs, but his willingness to give away and share his knowledge. His white papers are truly amazing and humorous at the same time.
After reading the "EL Pipe-o" white paper ( they smoked 26" 300 watt woofers ), and seeing his Rolling Stones pix ( on this site ) I *do* hope that he is protecting his hearing!
Going from 40W to 60W is less than 2 dB difference - with at least a 60W increase in waste heat.
Are you sure that you need the power? Look at the power you use for normal listening. I consider 90 dB pretty darned loud. I'd be surprised if you really need more than a 5-10W unless your room is huge and speakers inefficient.
The "catch" with the Aleph design is they don't like low impedance loads unless you bias for them. use the AXE-1.2 spreadsheet and see what happens to output power at low impedances. If you can use plenty of bias, it is not an issue, but then the heat load goes up.
That said, to get 60W or so, you can use the standard circuit with an additional quad of output devices (8 total), huge heat sinks and a transformer that will give you at least 18.5 volt rails loaded (14-15V secondaries ought to do) and you're in there. Set the total bias at 4 amps (0R5 source resistors)
By huge heat sinks, I mean plan on lots of metal. I have some coming for a project the size you specified that will be 7" high, 8.25" wide with 3" fins. Two of these per channel are predicted to keep my sink temperatures down to a cozy 54C with the junction temperatures at 97C. That's 18 pounds of heat sink per channel.
EDIT: BTW, the AX is a difficult first project. You might want to consider a straight aleph first, since it will be a bit easier to get running right. Although there are plenty of AX success stories out there, there are also lots of frustrated inexperienced builders.
Are you sure that you need the power? Look at the power you use for normal listening. I consider 90 dB pretty darned loud. I'd be surprised if you really need more than a 5-10W unless your room is huge and speakers inefficient.
The "catch" with the Aleph design is they don't like low impedance loads unless you bias for them. use the AXE-1.2 spreadsheet and see what happens to output power at low impedances. If you can use plenty of bias, it is not an issue, but then the heat load goes up.
That said, to get 60W or so, you can use the standard circuit with an additional quad of output devices (8 total), huge heat sinks and a transformer that will give you at least 18.5 volt rails loaded (14-15V secondaries ought to do) and you're in there. Set the total bias at 4 amps (0R5 source resistors)
By huge heat sinks, I mean plan on lots of metal. I have some coming for a project the size you specified that will be 7" high, 8.25" wide with 3" fins. Two of these per channel are predicted to keep my sink temperatures down to a cozy 54C with the junction temperatures at 97C. That's 18 pounds of heat sink per channel.
EDIT: BTW, the AX is a difficult first project. You might want to consider a straight aleph first, since it will be a bit easier to get running right. Although there are plenty of AX success stories out there, there are also lots of frustrated inexperienced builders.
But we got you through it to a working amp, right Terry?
There are plenty of people who are good at remote troublshooting who are willing to help if you get stuck. I just think you'll enjoy your project more if it works right the first time out. It will seem to sound better, too. My "works when initially powered up" projects do. Psychoacoustics at work again.
There are plenty of people who are good at remote troublshooting who are willing to help if you get stuck. I just think you'll enjoy your project more if it works right the first time out. It will seem to sound better, too. My "works when initially powered up" projects do. Psychoacoustics at work again.
Aleph X
Hi Guys,
Thanks for the input. I guess the 40 watt will be plenty. I have a small room and efficient 8 ohm speakers... Plus I listen fairly close.
I can tell this won't be an easy build, but really want to hear the X and my not have time to build another project after this.
Thanks for your input,
Luke
Hi Guys,
Thanks for the input. I guess the 40 watt will be plenty. I have a small room and efficient 8 ohm speakers... Plus I listen fairly close.
I can tell this won't be an easy build, but really want to hear the X and my not have time to build another project after this.
Thanks for your input,
Luke
![dsc00548[1].jpg](/community/data/attachments/30/30790-dcaf19bd60f3edfc84c1969429cd2c48.jpg)
Gilfo1,
I'll echo BobEllis' remarks. I built an Aleph-X with 50W output, and with that amplifier for the most part I listen at levels of 1-2W output, and even when I crank the volume for a good rockin-out session when the wife's not home, I never using more than 10W. I have 89dB/W/m sensitivity speakers in an ~400sqft room.
Also on the amp building vs. experience level, my first project was a Zen, then moved up to building an Aleph, then graduated to building an Aleph-X. The leasons learned along the way were a major help when I had to troubleshoot the Aleph-X.
Cheer, Terry
I'll echo BobEllis' remarks. I built an Aleph-X with 50W output, and with that amplifier for the most part I listen at levels of 1-2W output, and even when I crank the volume for a good rockin-out session when the wife's not home, I never using more than 10W. I have 89dB/W/m sensitivity speakers in an ~400sqft room.
Also on the amp building vs. experience level, my first project was a Zen, then moved up to building an Aleph, then graduated to building an Aleph-X. The leasons learned along the way were a major help when I had to troubleshoot the Aleph-X.
Cheer, Terry