Mark A. Gulbrandsen said:
...or shield it. I see you're getting 50Hz and harmonics coupled in on your test plots. The big naked input cap is a possible source. Worth checking for for another 10dB of free noise floor.
(I just happened to recently find that's where the last of the PSU noise in my own current design was coming from. I opted to kill off the coupling caps and go to a transformer input [CMLI-15] rather than a servo.)
Buildong
Hi all, I'm new in here, but I'm building these amps at the moment.
will make some changes on the pcb (some parts are more easy to find here in a different size)
The conductor will be silver, and with 100um thick (each side)
Would like to ask some questions from Alexw88, but I'm blocked -PLS check your mail on www.shine7.com
P.S.: I could send PCB-s naked and filled as well in about 3-4 weeks if it's needed 2 someone (Hungary/Europe) !!!
Hi all, I'm new in here, but I'm building these amps at the moment.
will make some changes on the pcb (some parts are more easy to find here in a different size)
The conductor will be silver, and with 100um thick (each side)
Would like to ask some questions from Alexw88, but I'm blocked -PLS check your mail on www.shine7.com
P.S.: I could send PCB-s naked and filled as well in about 3-4 weeks if it's needed 2 someone (Hungary/Europe) !!!
First of all, I would like to know what's changes if I use a biger (10 pF) capacitor? It's hard to find this 8,2pF at 200V in SMD.
he other H2F is dhe Dale WSR resistor. What shall I use??? wirewound?
I would like to know, why did you choose the LL 1545 A?
I would like to use the LL 1690.
I`ve tryed 2 understad the differences between them, but I`m not good enough for it.
Could you please check it for me, and give me some suggestions in it???
I don`t know what kind of pre-amp will I use with it, but if Good
helps me I will buy a tube thing from www.transcendentsound.com
I would like to deliver 2X150 Watts (on 8 Ohm) per SIDE
So I build a dual mono push-pull amp per side for biamping.
I`m not shure how shall I connect these audio transformers in this case?
just simply split the signal after the transformer?
or I should get 2 transformer per side? (this would make me a bit unhappy a bit)
he other H2F is dhe Dale WSR resistor. What shall I use??? wirewound?
I would like to know, why did you choose the LL 1545 A?
I would like to use the LL 1690.
I`ve tryed 2 understad the differences between them, but I`m not good enough for it.
Could you please check it for me, and give me some suggestions in it???
I don`t know what kind of pre-amp will I use with it, but if Good
helps me I will buy a tube thing from www.transcendentsound.com
I would like to deliver 2X150 Watts (on 8 Ohm) per SIDE
So I build a dual mono push-pull amp per side for biamping.
I`m not shure how shall I connect these audio transformers in this case?
just simply split the signal after the transformer?
or I should get 2 transformer per side? (this would make me a bit unhappy a bit)
10pF should be fine, the value is not very critical.
For the Dale WSR resistor, you can use any 3W resistor instead, wirewound would be fine.
I use LL1545A because it is available from the online stone that I used to buy things. LL1690 would also work, may be even better as it can handle higher level.
"So I build a dual mono push-pull amp per side for biamping."
If you want to do bi-amp, would you use a digital crossover to split the signal for the tweeter and woofer? In this case you need 2 transformers per channel.
or if you just feed the same line signal to 2 amps, then you can split the signal after the input transformer, in this case only 1 is needed.
For the Dale WSR resistor, you can use any 3W resistor instead, wirewound would be fine.
I use LL1545A because it is available from the online stone that I used to buy things. LL1690 would also work, may be even better as it can handle higher level.
"So I build a dual mono push-pull amp per side for biamping."
If you want to do bi-amp, would you use a digital crossover to split the signal for the tweeter and woofer? In this case you need 2 transformers per channel.
or if you just feed the same line signal to 2 amps, then you can split the signal after the input transformer, in this case only 1 is needed.
Thanks for the infos, than I will buy the 1690.
I'm not shur about this bi-amp stuff, but I have a nice speaker ( home made REAL high end stuff) and I want to amp them from a stereo (or in this case a dual mono amp to avoid ground loop in my sistem (since the Xo's are on a separeted board)
I don't want to use any digital what'snotever in my signal path.
I will just simply split the signal.
Thanks for the info Alex!
Hipchek: I will have a lot of board.
Made with 100 micron silver, but some thigs must be changed (input, output and power connects, becouse I could't find those thing at that size here)
everyting will be the same
will cost about 10$ plus P&P per board, but I'm not shure yet.
And It's will be available all (or olny the SMD parts) insalled. 4 another small charge.
I can't send mail, I'm under moderation at the moment.
It's would be fine if you could send me the resistors (0,1% or tighter) (i will build 16 boards for the start, and mor in the future) and I will send you some boards in the prices of the resistors?? Is it O.K. 4 you????
I'm not shur about this bi-amp stuff, but I have a nice speaker ( home made REAL high end stuff) and I want to amp them from a stereo (or in this case a dual mono amp to avoid ground loop in my sistem (since the Xo's are on a separeted board)
I don't want to use any digital what'snotever in my signal path.
I will just simply split the signal.
Thanks for the info Alex!
Hipchek: I will have a lot of board.
Made with 100 micron silver, but some thigs must be changed (input, output and power connects, becouse I could't find those thing at that size here)
everyting will be the same
will cost about 10$ plus P&P per board, but I'm not shure yet.
And It's will be available all (or olny the SMD parts) insalled. 4 another small charge.
I can't send mail, I'm under moderation at the moment.
It's would be fine if you could send me the resistors (0,1% or tighter) (i will build 16 boards for the start, and mor in the future) and I will send you some boards in the prices of the resistors?? Is it O.K. 4 you????
BPA 300 available
For everybody who left to buy BPA 300 groupbuys
by alexw88 now the boards are available
You can look in ebay with reasonable prize
http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&rd=1&item=380055682406&ssPageName=STRK:MESE:IT&ih=025
Hope you have a big smile with BPA 300
Regards, Jeffry
For everybody who left to buy BPA 300 groupbuys
by alexw88 now the boards are available
You can look in ebay with reasonable prize
http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&rd=1&item=380055682406&ssPageName=STRK:MESE:IT&ih=025
Hope you have a big smile with BPA 300
Regards, Jeffry
Attachments
Hi Alex,
Surely, I must not be the first one to ask this question.
But what is the process to safely measure the DC offset of each chip individually without risking damaging the chips?
Do you connect source and power and then fire it up and then measure DC offset?
Do you measure DC offset across the output 3W resistors & common ground?
best regards,
Evan
Surely, I must not be the first one to ask this question.
But what is the process to safely measure the DC offset of each chip individually without risking damaging the chips?
Do you connect source and power and then fire it up and then measure DC offset?
Do you measure DC offset across the output 3W resistors & common ground?
best regards,
Evan