azur a540 mod
Hi Salas, guys , just a quick update
Tried the 9V batt, I like the sound but humming badly in lower registers. sweet nice mid and high-bit edgy this one. got about 7 LP's with the batt while rudimentary setting up the MC cart.
Using 7809 - 550, hum mostly gone!, I think I missed the sweetness of 9V batt
So my target is to have more tighter bass, sweet- transparent mid & high
Quite a thrill to hear my kiseki blue silver again
. Thank you Salas ! I still have some questions though he he,
what is the optimum drain voltage? my sk170 idss is 8.5mA, what load is best for kiseki? is bypassing the 1000uF C's with 100nF recommended?
Other suggestions very well welcomed (tracking force, VTA, etc..)
Thanks & here is the pic
TeguhPS
Hi Salas, guys , just a quick update
Tried the 9V batt, I like the sound but humming badly in lower registers. sweet nice mid and high-bit edgy this one. got about 7 LP's with the batt while rudimentary setting up the MC cart.
Using 7809 - 550, hum mostly gone!, I think I missed the sweetness of 9V batt
So my target is to have more tighter bass, sweet- transparent mid & high
Quite a thrill to hear my kiseki blue silver again
. Thank you Salas ! I still have some questions though he he, what is the optimum drain voltage? my sk170 idss is 8.5mA, what load is best for kiseki? is bypassing the 1000uF C's with 100nF recommended?
Other suggestions very well welcomed (tracking force, VTA, etc..)
Thanks & here is the pic
TeguhPS
Attachments
Some hum when using the 7809 and 550C multiplier with 1000uF caps, must be no signal shielding, top open, any possible ground loop. Very unlikely to be ripple, you had more hum with batteries, that points elsewhere.
For Kiseki Blue, try 150R load.
For 8.5mA IDSS use R1 (common drain load resistor) 120R. That will bring the gain to 17dB since your cart is not really low MC (0.4mV?) and the voltages right. Maybe you get a bit of roughness due to buzz or EMI or much gain, don't know what sonics the main phono does also.
Use coaxial for signal in-out, at least twist those you have tightly, watch the quality of the 0.47u output capacitor. Close the top. You can play with bypasses on ecaps etc.
For Kiseki Blue, try 150R load.
For 8.5mA IDSS use R1 (common drain load resistor) 120R. That will bring the gain to 17dB since your cart is not really low MC (0.4mV?) and the voltages right. Maybe you get a bit of roughness due to buzz or EMI or much gain, don't know what sonics the main phono does also.
Use coaxial for signal in-out, at least twist those you have tightly, watch the quality of the 0.47u output capacitor. Close the top. You can play with bypasses on ecaps etc.
good morning Salas, my Rload is now 150R. I will take care of those dangling listz wire strings. I think hum is largely due to mediocre transformer (gets hot even with no load), wiring & open top.
I use 0.47uF K73-16, will play with bypasses for sure
forgot this, the main phono sound is tailored for sumiko black pearl, sounds just the way I liked it, only less transparent
Thanks
I use 0.47uF K73-16, will play with bypasses for sure
forgot this, the main phono sound is tailored for sumiko black pearl, sounds just the way I liked it, only less transparent
Thanks
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But where did you get the drawing ?
What about the component´s values ? are these your choices ?
I have tried 14nF7 still dry, no I have 15nF73 mids & highs come back, VTF 2.5gr.
Finally learne the problem doesn't that don't have highs, the problems was that with 15nF24 loses the mids so when increased value till 15nF73 I have more mids & highs, so guys warning to lowering a lot of the value because instead to have more highs you lose also mids.
Finally learne the problem doesn't that don't have highs, the problems was that with 15nF24 loses the mids so when increased value till 15nF73 I have more mids & highs, so guys warning to lowering a lot of the value because instead to have more highs you lose also mids.
Of course, I experimented with 100n, 47n, 33n, 10n, 1n, 470p, 120p, 40p, 25p, 10p.
I found that the bigger the cap, the more influence it makes in the mids.
In one build I have 10n because It lacked mids.
In the other build I have 10p because I only needed more highs.
The effect also depends on the type of cap. For more presence in the mids I found a good MKP is best. For highs a SM or Teflon is the best.
I found that the bigger the cap, the more influence it makes in the mids.
In one build I have 10n because It lacked mids.
In the other build I have 10p because I only needed more highs.
The effect also depends on the type of cap. For more presence in the mids I found a good MKP is best. For highs a SM or Teflon is the best.
I need to install a gnd lift in my rig.
I found that sometimes it hums, depending on witch system it is connected to. In my system I removed the hum by using an unearthed mains connection.
I am not sure the best way to do it... should I keep the case connected to mains earth and internally isolate the GND from the mains earth or should I keep the case connected to schematic GND and isolate it from mains earth ?
I found that sometimes it hums, depending on witch system it is connected to. In my system I removed the hum by using an unearthed mains connection.
I am not sure the best way to do it... should I keep the case connected to mains earth and internally isolate the GND from the mains earth or should I keep the case connected to schematic GND and isolate it from mains earth ?
