Looks great! I am impressed at how compact it is with the P2P. I can't wait to hear your listening impressions of the finished amp. What else do you have to do to it before you are done?
--
Brian
--
Brian
One thing I didn't mention is that my front end board doesn't contain output active current circuit. I'm making additional small boards for that and mount them directly on output boards. So that's one thing to finish and then connect everyting together. But I'm not rushing, because the chase is better than the catch.😉
Nice Job Peter on the P2P,
Reading your posts on Freds CCS did you used two of the J501's? Looking at you circuit I only see what appears to be a LM329 and one J501.
R2 in Fred's CCS did you use a varible resistor or how
did you calc. desired current output.
Finally,
Do you know of any sources for the J501 or J505 in the states??
Thanks
Reading your posts on Freds CCS did you used two of the J501's? Looking at you circuit I only see what appears to be a LM329 and one J501.
R2 in Fred's CCS did you use a varible resistor or how
did you calc. desired current output.
Finally,
Do you know of any sources for the J501 or J505 in the states??
Thanks
Check the other thread for sources for J501 (at the end). I used J505, which I had for years in my box. I used variable resistor for current, but when I set everything, I'll replace it with a regular one. I'm using 300 ohm drain resistors for increased current. All you have to do, is to adjust the voltage drop on those resistors for 4-5V.
Current diode
For biasing the LM329 anything in the 0.6 mA to 6mA range will be fine.
Fred
http://www.mouser.com/index.cfm?han...h&criteria=J504&searchby=PartNumber&x=17&y=12
For biasing the LM329 anything in the 0.6 mA to 6mA range will be fine.
Fred
http://www.mouser.com/index.cfm?han...h&criteria=J504&searchby=PartNumber&x=17&y=12
I have read in another thread that somebody achieved better sound of his Aleph when 0.5W, 9.1V zener was biased higher. I believe it was around 5mA as opposed to 2mA or so.
power supply question
Do you see a problem if I use a seperate power supply, with its own transformer and filter caps, to power the diff stage? My idea is to power the front-end all the time, keep it nice and warm and stable for action. Hopefully the DC drift will be lower, too. The main switch will turn on the power to the transformer for the output stage only. Any comment.
Thanks,
Kinjeo
Do you see a problem if I use a seperate power supply, with its own transformer and filter caps, to power the diff stage? My idea is to power the front-end all the time, keep it nice and warm and stable for action. Hopefully the DC drift will be lower, too. The main switch will turn on the power to the transformer for the output stage only. Any comment.
Thanks,
Kinjeo
🙂 Thanks Fred & Peter, I appreciate the vote of confidence. I'd be happy to act as Aleph-X comittee chair, and I guess my first order of business would be to organize the PCB efforts, which are off to a good start, but seem to have fizzled a bit with the ensuing discussions... provided, of course, that this is OK with wessol, carpenter, and tvi... and, of course, if I have the support of the majority here.
Support? Other nominations? Votes for anarchy?
In the meantime, I'm going to create a new section in the wiki, just for the Aleph-X, which I volunteer to maintain. This section will document the evolution of the Aleph-X project, and have a separate section for the distilled "Aleph-X recipe".
Support? Other nominations? Votes for anarchy?
In the meantime, I'm going to create a new section in the wiki, just for the Aleph-X, which I volunteer to maintain. This section will document the evolution of the Aleph-X project, and have a separate section for the distilled "Aleph-X recipe".
tell me more........
If I observe genuine and immediate steps towards a finished product and not months of hashing out ideas, then I'd consider holding off on my endeavors. I'm not trying to sound high and mighty here, I just have AlehpX fever and the impatients that go with it (seems to me, that way back when, it was Peter, Nelson, or somebody who challenged us to get off our butts and do something). Also, beings that I'm a remodel carpenter, I'm use to grabbing my tools and tackling a project with the expectation of obtaining immediate results. This thread has gone on for a long time and the final product just never seems to materialize. I have faith that the brains in this group will converge and eventually a most wonderful pcb will evolve. If it's going to take months (years), then I can always build my layout today, and later, the upgraded version too.
Is it possible to create a base design with a plug in concept in mind? I once created a burgler alarm pcb using this format. I could unplug an old piece from the mother board and replace it with an upgrade. The application here is to be able to easily upgrade in power and reduced distortion with the addition of segmented modules that govern a particular section of the primary pcb.
Thanks for grabbing the reins, hifiZen
John Inlow
If I observe genuine and immediate steps towards a finished product and not months of hashing out ideas, then I'd consider holding off on my endeavors. I'm not trying to sound high and mighty here, I just have AlehpX fever and the impatients that go with it (seems to me, that way back when, it was Peter, Nelson, or somebody who challenged us to get off our butts and do something). Also, beings that I'm a remodel carpenter, I'm use to grabbing my tools and tackling a project with the expectation of obtaining immediate results. This thread has gone on for a long time and the final product just never seems to materialize. I have faith that the brains in this group will converge and eventually a most wonderful pcb will evolve. If it's going to take months (years), then I can always build my layout today, and later, the upgraded version too.
Is it possible to create a base design with a plug in concept in mind? I once created a burgler alarm pcb using this format. I could unplug an old piece from the mother board and replace it with an upgrade. The application here is to be able to easily upgrade in power and reduced distortion with the addition of segmented modules that govern a particular section of the primary pcb.
Thanks for grabbing the reins, hifiZen
John Inlow
John:
Well, I haven't hauled in on those reins just yet, but I think it would be good to have someone steering the project and coordinating efforts so that some progress can me made. I don't think I would have taken this step without a little prodding from our fellow forum members. I'm mostly waiting for tvi's blessing, since I don't want to step on his toes...
Also, we need people like you to take the initiative and dive right in! I think you're offer to do a group PCB effort, and AlephX "fever" really got the ball rolling on this. So please, don't slow down on account of your pokey forum-mates! Let's keep the momentum we've built up so far!
My thoughts are that you should stick to your plan to get a board made for those who can't wait, and want one <i>right away</i>. The coordinated effort with all the circuit variations and modifications incorporated will probably take a while, since we'll need to get the layout finished and prototyped for verification before we start sumbitting larger orders for manufacture. That means someone with good equipment and test / troubleshooting skills will need to actually build the circuit on the 1st-run proto version, so it could take a little while to accomplish this...
so, tvi:
do you think it's worthwhile to have a coordinated group effort to make a "unified" PCB layout? If so, would you be willing to contribute your layout for further development work as the reference board for the Aleph-X?
Well, I haven't hauled in on those reins just yet, but I think it would be good to have someone steering the project and coordinating efforts so that some progress can me made. I don't think I would have taken this step without a little prodding from our fellow forum members. I'm mostly waiting for tvi's blessing, since I don't want to step on his toes...
Also, we need people like you to take the initiative and dive right in! I think you're offer to do a group PCB effort, and AlephX "fever" really got the ball rolling on this. So please, don't slow down on account of your pokey forum-mates! Let's keep the momentum we've built up so far!
My thoughts are that you should stick to your plan to get a board made for those who can't wait, and want one <i>right away</i>. The coordinated effort with all the circuit variations and modifications incorporated will probably take a while, since we'll need to get the layout finished and prototyped for verification before we start sumbitting larger orders for manufacture. That means someone with good equipment and test / troubleshooting skills will need to actually build the circuit on the 1st-run proto version, so it could take a little while to accomplish this...
so, tvi:
do you think it's worthwhile to have a coordinated group effort to make a "unified" PCB layout? If so, would you be willing to contribute your layout for further development work as the reference board for the Aleph-X?
sounds great!
It's amazing what a little validation can do to one's ego (I'm referring to mine). Thanks HifiZen, I think you'll make an excellent chairman.
John Inlow
It's amazing what a little validation can do to one's ego (I'm referring to mine). Thanks HifiZen, I think you'll make an excellent chairman.
John Inlow
HiFiZen,
aside from Fred tire-kicking posts, he has expressed opposition toward group purchases and he is probably just waiting to criticize and pick apart any results that will be coming out of this effort no matter how good they are, I think it is a very good idea for someone to take charge of the whole thing.
Given that you demonstrated superior knowledge on the subject it might as well be you to lead the Aleph X project.
aside from Fred tire-kicking posts, he has expressed opposition toward group purchases and he is probably just waiting to criticize and pick apart any results that will be coming out of this effort no matter how good they are, I think it is a very good idea for someone to take charge of the whole thing.
Given that you demonstrated superior knowledge on the subject it might as well be you to lead the Aleph X project.
back from the great diyAudio outage...
Whew! That was unpleasant. I hope the correct DNS info manages to get out there and propogate quickly.
Peter D:
A few pages back, you posted a pic of your P2P wired current source... what's the fuzzy "hair" that your ZVP mosfet is wearing?
Whew! That was unpleasant. I hope the correct DNS info manages to get out there and propogate quickly.
Peter D:
A few pages back, you posted a pic of your P2P wired current source... what's the fuzzy "hair" that your ZVP mosfet is wearing?
OK, well I'm going to go ahead and start some organization here... first thing:
carpenter:
Since your effort is already well underway, and I presume you're already in contact with the interested buyers, I think you should continue to coordinate that effort. Maybe just leave a few days for the site to recover from the DNS outage, and allow the members to catch up on what is going on...
carpenter:
Since your effort is already well underway, and I presume you're already in contact with the interested buyers, I think you should continue to coordinate that effort. Maybe just leave a few days for the site to recover from the DNS outage, and allow the members to catch up on what is going on...
Current AX pcb art (a chance to brag about Shawn's AX)
I have just given Shawn Wessel's AX a listen and find it to be a real joy. I just love my Pass Zen and didn't expect such a dramatic improvement in sound quality. I can best describe the sound as silky, without distortion mixed into the music; the Zen has a bit of second harmonic distortion. Both have a similar silky quality, but, the AX (minus the distortion) is more revealing. The music has an "edge" that I'm not accustom too. I'm using JBL 2446 loaded paper mache tractrix horns. They have tremendous authority with Shawn's amp. Now, with Shawn's AX, the musician, David Sanborn, play's a sax that can cut to the bone in one moment and sooth and caress in the next. With the Zen, David is "nice".
I notice a slight (very slight) amount of hum produced by the AX. I don't see any chokes in the power supply and the addition of couple may help. I also noticed that the gain on this unit is quite sensitive; ie. I have to operate the tri-amp x-over output to the AX at a much lower level than the rest of the amplifiers in the system; we're talking a dial setting of 12:00 for the other amps and 9:00 for the AX. Perhaps lowering the sensitivity in the AX will lower the hum threshold.
Regardless of what we do to improve this unit, the endeavor is well worth the effort. What a rewarding experience it's been to listen to Shawn's project.
Thank you,
John Inlow
I have just given Shawn Wessel's AX a listen and find it to be a real joy. I just love my Pass Zen and didn't expect such a dramatic improvement in sound quality. I can best describe the sound as silky, without distortion mixed into the music; the Zen has a bit of second harmonic distortion. Both have a similar silky quality, but, the AX (minus the distortion) is more revealing. The music has an "edge" that I'm not accustom too. I'm using JBL 2446 loaded paper mache tractrix horns. They have tremendous authority with Shawn's amp. Now, with Shawn's AX, the musician, David Sanborn, play's a sax that can cut to the bone in one moment and sooth and caress in the next. With the Zen, David is "nice".
I notice a slight (very slight) amount of hum produced by the AX. I don't see any chokes in the power supply and the addition of couple may help. I also noticed that the gain on this unit is quite sensitive; ie. I have to operate the tri-amp x-over output to the AX at a much lower level than the rest of the amplifiers in the system; we're talking a dial setting of 12:00 for the other amps and 9:00 for the AX. Perhaps lowering the sensitivity in the AX will lower the hum threshold.
Regardless of what we do to improve this unit, the endeavor is well worth the effort. What a rewarding experience it's been to listen to Shawn's project.
Thank you,
John Inlow
Excellent! Good to finally hear some direct comparisons, especially with other designs like the Zen, which should be familiar to many of the forum members.
It's good to have the group back.....
I was going through withdrawals. I hope that we never go down again!
John Inlow
HifiZen, and anyone else who's interested, I have the pcb artwork being converted to "gerber". It should take place next week. This looks like it will set me back $160.00 or so. It's worth it to me though; this amp sound sooooooo good.
I remember Brian offering to convert the pcb art for me. It seems like a lot to ask, Brian, and I do appreciate the offer, but, I would imagine school keeps you very busy.
I was going through withdrawals. I hope that we never go down again!
John Inlow
HifiZen, and anyone else who's interested, I have the pcb artwork being converted to "gerber". It should take place next week. This looks like it will set me back $160.00 or so. It's worth it to me though; this amp sound sooooooo good.
I remember Brian offering to convert the pcb art for me. It seems like a lot to ask, Brian, and I do appreciate the offer, but, I would imagine school keeps you very busy.
ummmm - suggestion
Suggestion - while we're waiting for the site to come back up - why not see if it can be done in one shot? - I thought John said he didn't mind waiting some as long as it wasn't going to be a long time -
I guess I'm just thinking that this is a somewhat narrow niche of people overall - wouldn't our group be better off as a whole to agree on one board as a first version - signed off on, so to speak, by most of the potential users.
Then get that group of boards in use and when the time comes make changes to that board - a 2nd Gen of the same board - with the first board as a standard to go by?.
Off the top of my head, it seems that there would be more potential benefits to having only one version of 1st generation boards out there.
We split the focus of developemental paths and reduce the benefits of group purchasing power if we start off with two versions.
We've got some sharp people here - it's usually harder to get smart people to agree because they are bright😀 - I think we've got a lot of the elements in place - lets keep pushing it into one first generation board-
or on the other hand, everybody might figure -
" a camel is a horse designed by committee "
Ken
Suggestion - while we're waiting for the site to come back up - why not see if it can be done in one shot? - I thought John said he didn't mind waiting some as long as it wasn't going to be a long time -
I guess I'm just thinking that this is a somewhat narrow niche of people overall - wouldn't our group be better off as a whole to agree on one board as a first version - signed off on, so to speak, by most of the potential users.
Then get that group of boards in use and when the time comes make changes to that board - a 2nd Gen of the same board - with the first board as a standard to go by?.
Off the top of my head, it seems that there would be more potential benefits to having only one version of 1st generation boards out there.
We split the focus of developemental paths and reduce the benefits of group purchasing power if we start off with two versions.
We've got some sharp people here - it's usually harder to get smart people to agree because they are bright😀 - I think we've got a lot of the elements in place - lets keep pushing it into one first generation board-
or on the other hand, everybody might figure -
" a camel is a horse designed by committee "
Ken