Optivol
is a simple shunt LED/LDR optocouplers, the series resistor are 27k (at fist I put a Dale but tantalum is a must ) that work well in jfet riaa (you can remove the resistor on out caps) change if the amp need...
the pot control the light on led ,ie you can put where you want !and ldr near the out
need 24vdc or so ,for 17€ shipping incluse
you can only win !! a lot better then alps blu
problem,now is out of stock but contact Greg ,is fine men ,for preorder
alternative the ligthspeed on Diyaudio that are full ldr but parts and match are problem (you can order two matched optivol)
decent pot start with TKD at 61$
alternative 41-step Attenuator but $$$ link
is a simple shunt LED/LDR optocouplers, the series resistor are 27k (at fist I put a Dale but tantalum is a must ) that work well in jfet riaa (you can remove the resistor on out caps) change if the amp need...
the pot control the light on led ,ie you can put where you want !and ldr near the out
need 24vdc or so ,for 17€ shipping incluse
you can only win !! a lot better then alps blu problem,now is out of stock but contact Greg ,is fine men ,for preorder
alternative the ligthspeed on Diyaudio that are full ldr but parts and match are problem (you can order two matched optivol)
decent pot start with TKD at 61$
alternative 41-step Attenuator but $$$ link
from Zen mod, ldr+JC buffer kit .....are you sure that need buffer?
http://www.diyaudio.com/forums/showthread.php?s=&threadid=139113
http://www.diyaudio.com/forums/showthread.php?s=&threadid=139113
Generally speaking, the smaller (your system can support), the better. Salas is absolutely right. Check the input impedance of the following component and calculate the right value for 10 - 15 Hz.RCruz said:
As we are dealing with a less than perfect source, even if you cut a bit of low frequencies, is not that bad. Think about all the problem related to the warp of records and/or plinth resonance.
Hi Salas
Just replaced all the resistors and placed everything in a new case.
It played for a while but only in one channel.. the right one only thundered and spet.
After cleaning the pcb, I have only rubble and no sound coming from the speakers.
What should be wrong ?
GND connections ?
Ricardo
Just replaced all the resistors and placed everything in a new case.
It played for a while but only in one channel.. the right one only thundered and spet.
After cleaning the pcb, I have only rubble and no sound coming from the speakers.
What should be wrong ?
GND connections ?
Ricardo
Maybe too hot a desoldering & soldering cycle took out some semiconductor(s)? I would check the Zener voltage and the BC550 collector voltage. Also the drain voltages, and compare to the healthy channel. Also check for wrong new resistor values. If the channel that played initially, is silenced too now, then the problem may took the PSU too. Check for having correct B+.
Hi Salas
After a new clenup, the good sounding channel is grouling while the other is playing....
Zeners are good (both 8.4v)
Collector bC550 (Good channel 12.9 bad channel 12.33 ~ 12.29)
Between R6 º C2 (Good 12.2 bad 9 ~ 12)
Output cap (Good 10.37 bad 9.86 ~11.1)
Where should be the problem ?
Ricardo
After a new clenup, the good sounding channel is grouling while the other is playing....
Zeners are good (both 8.4v)
Collector bC550 (Good channel 12.9 bad channel 12.33 ~ 12.29)
Between R6 º C2 (Good 12.2 bad 9 ~ 12)
Output cap (Good 10.37 bad 9.86 ~11.1)
Where should be the problem ?
Ricardo
