右面 Channel 細聲 D? / Lower Output in Right Channel

Alfcat if you like i can guide you to search for the problem.
Al you need is a CD with a test signal between 400Hz or 2Khz, 1 Khz is just fine. And a multimeter. First measure the output signal for left and right channel with the testcd on play and the meter on AC/voltage. You must get a reading about 1000mV(1 Volt). Tell what your measurements are. Measure between signal and ground/shield of the output.

Ronny

Oke , now it is confirmed that the right channel has a lower output and you have the right equipment.

Next measure the test signal between the jensen caps where you have connected the wires from the dac-ah and ground for left and right channel  When here the signals are even then the problem is beyond the caps other wise we must search near the DAC-ah. Let me now your measurements.

http://www.hififever.com/forum/download.php?id=8076

Below i have the schematic of the analog outputstage, you need to measure ( same way you did above ) green points 1,2,3,4,5 of one channel and 6,7,8,9,10 of the other channel. If there is a difference between left and rights there you must search for the mismatch( defect).
The orange path is the way the audio travels.

Alfcat are the measurements made with the meter on AC? Because values of point 3,4,8 and 9 are very high.
But the difference starts at point 3 and 8. So it is most likely that the 82 K resistors are the 2 you must change. One of them has a different value now. If you replace them use 1 or 2 watt types. If this not works you can replace the two 15K resistors. Because with yhe 82K and the 15 K you set the gain of the first tube.

Alfcat . your right i used the wrong schematic the resistors who are suspect are the 56K and the 33K ones. When you remove the tube you can measure the resistance with the multimeter. So you can detect the defect one. The resistance should be the same for left and right channel. I do not know the excact position because i do not have a MHZS player at home. Just look on the text of the PCB or check the resistor color code or measure, they are near the first tube.

When you measure a audio test signal, set your meter to AC. This reading you get is then only the audiosignal without the superposed DC voltage.

When this happen it is a pitty. Check if the lens is clean. And be sure if the flatcable is installed right.

About the measurements do not measure DC but AC with the testsignal on. The DC is not interresting. Please tell me your readings at the several points.

I can not recall the 150 Ohm resistors. May be for the filaments power supply.

The 470K resistors you can change but now you can measure AC voltage i think may be the problem is the DAC. Please measure again the testsignal in AC at point 1 and 6 and before the jensen capacitors.

Well done, Alfcat. =D>

I am working on a new projekt. Building a OTL amp with 6C33C-B tubes.
I have 20 pieces of them. I looking at several schematics still i have not found the right one.

OTL amps do not have a outputtransformer. The tubes drives the speaker directly. I have some link on OTL and the schematic i like to build.

http://www.audiodesignguide.com/my/index.html#MY_OTL

With the above schematic you can drive normal 8 Ohm speakers and the amp is tested with 1 Ohm. Output power is 20 a 30 Watt at 8 Ohm.

http://www.currants.info/chinese ... w-gf/Rv-GM%2020.htm

An OTL amp does not sound like a tube amp, it is very linear and has maximum detail. It sounds less warm. But placement and detail is the best you can find. There is a design where you can build a 2 x 30 watt OTL amp for HK$ 3000. Look here.

http://www.audiodesignguide.com/my/index.html#MY_OTL

[quote:00bc7a9eed="alfcat"]Dear Koifarm,

Hmm... sounds interesting. A tube amp but really doesn't sound like one. So this OTL will be closer to Transistor Amplifiers, right?

If I like simple vocals, this won't be the perfect one for me. But if I like something more complicated e.g. orchestra, this will be a better choice. Am I correct?

CAT[/quote]

Yes, you are correct.

If you like vocals just take dynaudio speakers. I made them myself with dynaudio carspeakers. MD130 tweeters, MW150 mid/bass and MW170 woofer all in closed enclosure. The best i heard, used it now for 8 years.
I was stupid to sell them a half year ago. I am now collecting new dynaudio units to build them again. Everthing that comes near my dynaudio speakers are ready made dynaudio speakers cost more them HK$ 60000 a piece. The cost to make them self is about HK$ 10000 for 2 speakers.