i am testing it with old car speakers so i dont worry..i dont know what to do..bias is ok..voltage is ok..but there is low sound..
How do you what the level your sound card is putting out? You probably need to use a scope to check it at the input. Or use a known good source.
If you touch the input with your finger do you hear a hum?
If you touch the input with your finger do you hear a hum?
Is the hum louder than the music is when you plug it into the input? Then the problem may be your source.
there is no hum when i connect it to sound card..there is only a little music..emu sound card is a balanced card..i lost my mp3 player..i dont have any other source right now
umut1001 said:
No hum when connected to player - sounds like inputs dont have a shunt resistor.
The low-output - I have done the same thing before. Turned out one of the speaker terminals was touching the chassis. I would do the continuity test on the signal path...Make sure that inputs and outputs are isolated correctly.
umut1001 said:
did you converted your emu output to unbalanced ?
I bet that's culprit
edit :
to make my self more clear - you need to connect output from emu card in unbalanced manner .
I'm not familiar with your card - does it have sort of XLR connectors ?
in that case , tie 1&3 marked pins on XLR cable connector ; that;s gnd
pin No.2 is hot
No bias current on my F5
rdk845 said:
I'm having problem with my F5 having bias currents. Now I have taken out the channels from heat sink and slowsly increased the P1 and P2. But I don't see the voltage more than ~100mA. The voltage across the P2 never goes higher than ~3.2V even when I go the way up in N-channel part, while across P1 I can get higher than 4.2V. In both channels I can't get more than 0.1V across R11 and R12. I have replaced all transistors in N parts, and there is no change. Could anyone please let me know how I can go around finding the culprit? Thanks!
Sounds like you need to increase the values of R3 and R4 to develop
enough voltage. Try 3.3K or so.
😎
enough voltage. Try 3.3K or so.
😎
> i used 2sk1530 and sj201. bias is 1,5a and i see 2,83volts on r3 and r4..
The Toshibas have about 2.5V Vgs at 1A, so the 2.8 you see is about normal. I assume you are using 0R47 for source resistor.
Patrick
The Toshibas have about 2.5V Vgs at 1A, so the 2.8 you see is about normal. I assume you are using 0R47 for source resistor.
Patrick
Nelson Pass said:
Thanks Nelson. But I wonder why only N-type parts is like that, not P type part? Both left and right channels behave the same...
labjr said:
EUVL said:
now i connected the f5 amp to the speaker output of my denon pma495 r amp(denon amp has 70watt output for 4ohms) with a 13,6uf(paralel of 2x6,8uf) mkp coupling capacitor..i am surprised..amp is now playing loudly and very well 😀 there is no hum buzz or sth like that 😀 😀 i didnt understand..what is the input voltage of f5 amp?..i think i need a very high gain preamp
Chokes
Hello,
For the PS I'm thinking of a CLC
Browsing in the RS components I find some cheap common mode chokes of 10mH, 5A
http://be02.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=4890419
Can these chokes be used in the PS for an F5 ? One coil of the choke in series with the + supply and the other coil in series with the - supply.
Regards,
Danny
Hello,
For the PS I'm thinking of a CLC
Browsing in the RS components I find some cheap common mode chokes of 10mH, 5A
http://be02.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=4890419
Can these chokes be used in the PS for an F5 ? One coil of the choke in series with the + supply and the other coil in series with the - supply.
Regards,
Danny
umut1001 said:
now i connected the f5 amp to the speaker output of my denon pma495 r amp(denon amp has 70watt output for 4ohms) with a 13,6uf(paralel of 2x6,8uf) mkp coupling capacitor..i am surprised..amp is now playing loudly and very well 😀 there is no hum buzz or sth like that 😀 😀 i didnt understand..what is the input voltage of f5 amp?..i think i need a very high gain preamp
did you read what I wrote as Re - few posts above ?
you need few V for full blast from F5 , not speaker level from amp !
Re: Chokes
they're 5A just for AC current ;
what you need here are chokes for DC - mucho different animals ...
danny_66 said:
they're 5A just for AC current ;
what you need here are chokes for DC - mucho different animals ...
yes of course i read it.an f5 amp must play with few voltages.but my amp doesnt play with few voltage..i didnt understand..but now it is playing very good with amp output 😀 ..i didnt understand the problem.. bias is ok..voltage is ok..is the input sensitivity 1.5 volts for 25watts class a mode in normal conditions?
bias is ok..voltage is ok..is the input sensitivity 1.5 volts for 25watts class a mode in normal conditions?
umut1001 said:
you probably tried balanced output from your EMU card - to connect to F5 , which is equipped with unbalanced input .
what you need is to connect balanced feed in unbalanced manner .
I wrote you how , suspecting that you have XLR connectors on EMU side