No, it's not a big deal... it's pretty obvious. I'm almost 100% sure the problem is the Zener diodes anyhow. He was saying he couldn't get the source voltage above 0.7VDC which means it has to be that.
Cheers,
Owen
Cheers,
Owen
true, I agree the 0.7 is a bit of a giveaway and it should be obvious, but all the same i've reported my post to get it corrected, because if someone searches the thread for the setup procedure they might get my post in isolation rather than following the link.
What would be great is someone to gather all the important changes that need to be applied plus some important mods and post them on the first page of the thread if that is still possible. That would make it alot easier than reading 90+ pages... 😉
My two cents
Do
My two cents
Do
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thanks wintermute, that report post button really works!!
piccocchio, there really isnt any important mods to be made. the procedure i outlined is mentioned several times throughout this thread and the build thread. any new boards will have the protection diodes correctly placed (wont they opc?) so no tipis need building and the bias procedure is standard for any sabre IV stage where you have the ability to do so.
this thread is a good resource, but build info and further build pics really should be posted in the build thread.
piccocchio, there really isnt any important mods to be made. the procedure i outlined is mentioned several times throughout this thread and the build thread. any new boards will have the protection diodes correctly placed (wont they opc?) so no tipis need building and the bias procedure is standard for any sabre IV stage where you have the ability to do so.
this thread is a good resource, but build info and further build pics really should be posted in the build thread.
Yes, I spotted the back to back diodes on one picture. Indeed the 0.7V was pretty obvious that the zener were conducting.
Thanks for all your help. I'll change the diodes right away. Bye.
Thanks for all your help. I'll change the diodes right away. Bye.
It is working perfectly, once I installed the zener correctly. I installed all the matched quad and they tested remarkably close. I used a test CD I had that contain pure tone recorded at know volume. I used the 1Khz, 0dBV track and I after I matched the FET source voltage to the DAC output I got almost the same voltage for all of them.
I used my little balanced to single ended converter PCB to get the measurements.
Vout = 1.820 to 1.823Vac, 1Khz
THD = 0.060 to 0.062% (Using CLIO, seems to be the floor value for my setup, real distortion is probably lower since all measurements were the same..)
R 200 ohms Vdc voltage on all FET was close to 23.3V or 116ma going throught each FET.
After I replaced the quad and let stabilize in temperature, the Source voltage adjustment was very close from FET to FET and needed little adjustment.
I listed to all matched Quad using real music and sound is very good, lots of details, timing, gorgeous midrange. All very good to me.
I'll keep to Quad for me and my friend + 1 spare for now.
That left me with three matched Quad to sell. I already have two interested.
Send me a private email is interested.
Thank you all for your help.
I used my little balanced to single ended converter PCB to get the measurements.
Vout = 1.820 to 1.823Vac, 1Khz
THD = 0.060 to 0.062% (Using CLIO, seems to be the floor value for my setup, real distortion is probably lower since all measurements were the same..)
R 200 ohms Vdc voltage on all FET was close to 23.3V or 116ma going throught each FET.
After I replaced the quad and let stabilize in temperature, the Source voltage adjustment was very close from FET to FET and needed little adjustment.
I listed to all matched Quad using real music and sound is very good, lots of details, timing, gorgeous midrange. All very good to me.
I'll keep to Quad for me and my friend + 1 spare for now.
That left me with three matched Quad to sell. I already have two interested.
Send me a private email is interested.
Thank you all for your help.
Hi Algar,
Glad to hear to you got it all sorted, and also glad to hear you like the way it sounds. I've been thoroughly enjoying mine, both with headphones and with my main system, and I never really get tired of it.
I still need to machine up a nice chassis for it, but that is unfotunately a little ways down my things to do list.
You should put up some pictures of the completed unit when you get the chance!
Cheers,
Owen
Glad to hear to you got it all sorted, and also glad to hear you like the way it sounds. I've been thoroughly enjoying mine, both with headphones and with my main system, and I never really get tired of it.
I still need to machine up a nice chassis for it, but that is unfotunately a little ways down my things to do list.
You should put up some pictures of the completed unit when you get the chance!
Cheers,
Owen
Already 1 matched Quad sold, one pending, one left to sell. Send me a private email if interested. Thanks... SB
Hey qusp, watch the spelling, not piccocchio but pinnocchio plus you have all the red letters in there... Was this that week of the month? 😀
Seriously, I've been going post by post but cannot find that darn build thread anymore... Can you please send me a PM?
Thanks
Do
haha sorry mate, dont know what happened there; theres always some scatterings of red though, because i often dont bother with apostrophes; on internet forums i honestly couldnt care less about them. here is the build thread as with this one and others, watch out for the occasional interjection like on the last page or 2, i'm sure youve seen it before
Hi Algar,
You said you had reserved this quad for me but I did not get an answer from you after my last PM. Did you get it?
Thanks
Do
PCB Group Buy Update
I put one pcb back for me, to build it for a friend 😉
1. cersepn x 1
2. icewall x 2
3. pmchoong x 1
4. qusp x 1 this is tentative mate, but wanted to make sure my name was down
5. regal
6. randytsuch x 1
7. LK x1
8. greyrab x1
9. alexcount x1
10. adelias x1
11. Coolhead x1
12. Emphrygian x 1
13. tranhieu x 1
14. crazyfrog x 1
15. woresseo x 2
16. Pedefede x 1
17. Algar_emi x 1
18. ggetzoff x 1
19. syklab x1 + fets
20. Magsy x 1
I put one pcb back for me, to build it for a friend 😉
1. cersepn x 1
2. icewall x 2
3. pmchoong x 1
4. qusp x 1 this is tentative mate, but wanted to make sure my name was down
5. regal
6. randytsuch x 1
7. LK x1
8. greyrab x1
9. alexcount x1
10. adelias x1
11. Coolhead x1
12. Emphrygian x 1
13. tranhieu x 1
14. crazyfrog x 1
15. woresseo x 2
16. Pedefede x 1
17. Algar_emi x 1
18. ggetzoff x 1
19. syklab x1 + fets
20. Magsy x 1
Anyone wants out?
I would gladly grad 2 boards of NTD1 but if available 1 for sure... 😀
Anyways, count me in when available again
Ciao!
Do
I would gladly grad 2 boards of NTD1 but if available 1 for sure... 😀
Anyways, count me in when available again
Ciao!
Do
what's the minimum number of pcbs for each GB btw? sorry if this question is too obvious, I'm not very familiar with how things go here.
1. cersepn x 1
2. icewall x 2
3. pmchoong x 1
4. qusp x 1 this is tentative mate, but wanted to make sure my name was down
5. regal
6. randytsuch x 1
7. LK x1
8. greyrab x1
9. alexcount x1
10. adelias x1
11. Coolhead x1
12. Emphrygian x 1
13. tranhieu x 1
14. crazyfrog x 1
15. woresseo x 2
16. Pedefede x 1
17. Algar_emi x 1
18. ggetzoff x 1
19. syklab x1 + fets
20. Magsy x 1
21. Vitalica x2 + fets
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1. cersepn x 1
2. icewall x 2
3. pmchoong x 1
4. qusp x 1 this is tentative mate, but wanted to make sure my name was down
5. regal
6. randytsuch x 1
7. LK x1
8. greyrab x1
9. alexcount x1
10. adelias x1
11. Coolhead x1
12. Emphrygian x 1
13. tranhieu x 1
14. crazyfrog x 1
15. woresseo x 2
16. Pedefede x 1
17. Algar_emi x 1
18. ggetzoff x 1
19. syklab x1 + fets
20. Magsy x 1
21. Vitalica x2 + fets
22. Pinnocchio x 1
2. icewall x 2
3. pmchoong x 1
4. qusp x 1 this is tentative mate, but wanted to make sure my name was down
5. regal
6. randytsuch x 1
7. LK x1
8. greyrab x1
9. alexcount x1
10. adelias x1
11. Coolhead x1
12. Emphrygian x 1
13. tranhieu x 1
14. crazyfrog x 1
15. woresseo x 2
16. Pedefede x 1
17. Algar_emi x 1
18. ggetzoff x 1
19. syklab x1 + fets
20. Magsy x 1
21. Vitalica x2 + fets
22. Pinnocchio x 1