For those guys on this thread that wasn't informed and intersted to buy the Aleph J-X boards, go to this link, http://www.diyaudio.com/forums/showthread.php?postid=1879567#post1879567
sign up and pay for the boards to Peter. As far as I know, there's no such wiki set up for this group buy.
sign up and pay for the boards to Peter. As far as I know, there's no such wiki set up for this group buy.
PSU-Capacitory Group Buy
Peter excuse the of topic post, but as I wait for another set of your boards to build my 3rd pass amp my cost in psu parts is rising quickly. If there is enough interest, I am willing to undertake a mini group buy for caps. I have been using the Panasonic TSHA 35v 22000uf capacitors as seen in this link.
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=P6671-ND
If there is enough interest to purchase 200 caps i should be able to deliver them for $4 a cap in the states. Not to distract this thread please PM me if you are interested.
thanks, Nick
Peter excuse the of topic post, but as I wait for another set of your boards to build my 3rd pass amp my cost in psu parts is rising quickly. If there is enough interest, I am willing to undertake a mini group buy for caps. I have been using the Panasonic TSHA 35v 22000uf capacitors as seen in this link.
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=P6671-ND
If there is enough interest to purchase 200 caps i should be able to deliver them for $4 a cap in the states. Not to distract this thread please PM me if you are interested.
thanks, Nick
BOM For the AJ-X
Patrick,
Any chance I could get your help on a BOM for a 100w version such as your own? I would like to order my fets and am unsure of how many I should order as I will be ordering the matched already?
I would be buying enough jfets for all 5 boards as I can get them now and am not sure for how long.
I was thinking 5x matched pars of each 2SK170BL and 2SJ74. Would that be correct?
On the 6 output (R22-27)resistors should I be replacing those with the 100R/100W as you suggest?
On the drains of the Irfp240's (using 12 available spots) should I be using 910R/3W?
Sorry for all the questions but this is new waters for me and would like to get it right.
James
Patrick,
Any chance I could get your help on a BOM for a 100w version such as your own? I would like to order my fets and am unsure of how many I should order as I will be ordering the matched already?
I would be buying enough jfets for all 5 boards as I can get them now and am not sure for how long.
I was thinking 5x matched pars of each 2SK170BL and 2SJ74. Would that be correct?
On the 6 output (R22-27)resistors should I be replacing those with the 100R/100W as you suggest?
On the drains of the Irfp240's (using 12 available spots) should I be using 910R/3W?
Sorry for all the questions but this is new waters for me and would like to get it right.
James
So why do the boards have room for 6 mosfets when in the schematic
http://www.diyaudio.com/forums/attachment.php?s=&postid=1343785&stamp=1194303063
There are only 4 mosfets?
Hope someone can answer this. Seems like a valid question. The manual on FirstWatt also has a pic on it showing 4 per channel.
Uriah
http://www.diyaudio.com/forums/attachment.php?s=&postid=1343785&stamp=1194303063
There are only 4 mosfets?
Hope someone can answer this. Seems like a valid question. The manual on FirstWatt also has a pic on it showing 4 per channel.
Uriah
lol, I'm not even into this yet and think I am in over my head. So many variations on scematics and pcb lables from one project to another. I have read the various threads and such but was wondering if someone could help me with the bom?
I have looked at Patricks and the up amp. I have looked at Eric's Aleph-X info. Kinda having a hard time wrapping my mind around this.
I have looked at Patricks and the up amp. I have looked at Eric's Aleph-X info. Kinda having a hard time wrapping my mind around this.
Ok, I think I have the main PCB figured out as I found a BOM on the A30 WIKI page. Now I just need to figure out the bridge board and as far as I have looked it seems that those markings match the original J-X diagram.
I'll post my findings and go from there.
I am sure to have more questions but I will just take baby steps and try to find my answers.
James
I'll post my findings and go from there.
I am sure to have more questions but I will just take baby steps and try to find my answers.
James
Uriah:
Thanks. I do understand that a 200 watt / channel amp is only marginally more powerful than a 100 watt / channel amp, but I think the difference is noticeable in my main stereo. While it is possible that I'm kidding myself, previous experiences with a lower-powered amp (a friend's Classe 10) in place of my amps (Aleph 1.2 monos) have left me with the impression that the more powerful amplifier does a better job in controlling my speakers.
Based on my under-educated experience, my inclination is to try to build an amp that is at least as powerful as the amps it will replace.
If there is another explanation for the phenomena that I have described, I'd appreciate the education.
Regards,
Scott
Thanks. I do understand that a 200 watt / channel amp is only marginally more powerful than a 100 watt / channel amp, but I think the difference is noticeable in my main stereo. While it is possible that I'm kidding myself, previous experiences with a lower-powered amp (a friend's Classe 10) in place of my amps (Aleph 1.2 monos) have left me with the impression that the more powerful amplifier does a better job in controlling my speakers.
Based on my under-educated experience, my inclination is to try to build an amp that is at least as powerful as the amps it will replace.
If there is another explanation for the phenomena that I have described, I'd appreciate the education.
Regards,
Scott
Hi Scott,
Well, I do have a little listening experience with Classe and Pass amps. Little bit only.
I was way underwhelmed by the Classe and I have NEVER had an amp have more control over my speakers than the F5. It was absolutely stunning how that 25W amp beat my speakers into submission. The Classe really did a poor job controlling low end and it almost seemed that they were designed to for more 'silky' mids and 'chocolaty' low sounds. Marketing through first impressions of sound. The bass also, apart from being flabby, got boomy whenever there was a quick increase in volume and was pretty annoying. I heard the Classe at an audio store down the street on those B&W Nautilus and was really suprised to be wondering why this elite set up wasnt cutting it.
So, I am only guessing, but it may have simply been that you demand more from your audio equipment than a Classe could have ever given you and that I am betting most Pass Labs equipment would deal up in spades.
Uriah
Well, I do have a little listening experience with Classe and Pass amps. Little bit only.
I was way underwhelmed by the Classe and I have NEVER had an amp have more control over my speakers than the F5. It was absolutely stunning how that 25W amp beat my speakers into submission. The Classe really did a poor job controlling low end and it almost seemed that they were designed to for more 'silky' mids and 'chocolaty' low sounds. Marketing through first impressions of sound. The bass also, apart from being flabby, got boomy whenever there was a quick increase in volume and was pretty annoying. I heard the Classe at an audio store down the street on those B&W Nautilus and was really suprised to be wondering why this elite set up wasnt cutting it.
So, I am only guessing, but it may have simply been that you demand more from your audio equipment than a Classe could have ever given you and that I am betting most Pass Labs equipment would deal up in spades.
Uriah
Ok, New question for the day is...........
On the X daughter board how do I determine the values of RS and RP and what is thier purpose?
Also is there any peticular wattage I should use for the 100k pots in P1 or is .5w fine?
Last thing is, what tolerance should I be aiming for in my resistors? Is .1% overkill? Should I be spending the money on higher quality caps and resistors in the output stage or are there others in the amp board I should be looking at also?
Have most of the BOM worked out now I think and will put it up for evaluation when it is done.
Thanks guys.
James
On the X daughter board how do I determine the values of RS and RP and what is thier purpose?
Also is there any peticular wattage I should use for the 100k pots in P1 or is .5w fine?
Last thing is, what tolerance should I be aiming for in my resistors? Is .1% overkill? Should I be spending the money on higher quality caps and resistors in the output stage or are there others in the amp board I should be looking at also?
Have most of the BOM worked out now I think and will put it up for evaluation when it is done.
Thanks guys.
James