Very high frequency not so linear creatures that maybe oscillate easily especially if not having their dedicated sockets?
OK, so just getting ready for second switch on.
First test was sprawled out on the kitchen table, just to check nothin catastrophic, voltages ok etc.
I have built the boxes now. What a lot of work it's been. Still waiting patiently to try and play a record through it.
A few questions:
1. I have no fuses below 1A slow blow. No 300mA in my fuse collection. Dangerous to proceed with 1A for now? I'll buy some 300mA tonight.
2. What do we think about utilising tiny uF but surge-proof X and Y capacitors in the RAW power supply? I am trying to clean up my AC on my amps, particularly from pops and clicks when the fridge goes on and off etc. I am anticipating that a phono stage is particularly sensitive to AC surges. Someone said that it's best to fit them to the fridge, washing machine etc., to soak up the surges there, leaving the hifi unadulterated...I'm not sure I understand the consequences properly. What say you Salas/ wiser men than I?
3. The 4.7uF film cap in the shunt reg. I currently have a 22uF electro and the resistor, which I will eventually replace. I do have some spare quality 2.2uF film caps I could use here instead. Is the 4.7uF value critical? I seem to remember from previous Salas shunts that it's not.
4. My Tx is outputting 31.5vAC, and my phono stage looks like it will be running at 31vDC, rather low. What tricks can I employ to help lift it a little? Less lossy diodes? I already have the wire in place of the resistor in the RAW supply. Anything else?
Thanks as ever.
First test was sprawled out on the kitchen table, just to check nothin catastrophic, voltages ok etc.
I have built the boxes now. What a lot of work it's been. Still waiting patiently to try and play a record through it.
A few questions:
1. I have no fuses below 1A slow blow. No 300mA in my fuse collection. Dangerous to proceed with 1A for now? I'll buy some 300mA tonight.
2. What do we think about utilising tiny uF but surge-proof X and Y capacitors in the RAW power supply? I am trying to clean up my AC on my amps, particularly from pops and clicks when the fridge goes on and off etc. I am anticipating that a phono stage is particularly sensitive to AC surges. Someone said that it's best to fit them to the fridge, washing machine etc., to soak up the surges there, leaving the hifi unadulterated...I'm not sure I understand the consequences properly. What say you Salas/ wiser men than I?
3. The 4.7uF film cap in the shunt reg. I currently have a 22uF electro and the resistor, which I will eventually replace. I do have some spare quality 2.2uF film caps I could use here instead. Is the 4.7uF value critical? I seem to remember from previous Salas shunts that it's not.
4. My Tx is outputting 31.5vAC, and my phono stage looks like it will be running at 31vDC, rather low. What tricks can I employ to help lift it a little? Less lossy diodes? I already have the wire in place of the resistor in the RAW supply. Anything else?
Thanks as ever.
Last edited:
3. Use the 22uF until having proper value film cap to compare. Its important enough to have the right value options.
2. I think that using them XY at surge sources is the most effective.
1. Since you have checked it already for non catastrophic behavior use the 1A for now and have 300mA and 500mA T type soon. Depending on your transformers you must install fuses that don't blow at power on when the capacitors are charged but not much bigger than the value that blows. Some transformers have primary fuse spec on their label. If with two transformers on one IEC you double the rating.
2. I think that using them XY at surge sources is the most effective.
1. Since you have checked it already for non catastrophic behavior use the 1A for now and have 300mA and 500mA T type soon. Depending on your transformers you must install fuses that don't blow at power on when the capacitors are charged but not much bigger than the value that blows. Some transformers have primary fuse spec on their label. If with two transformers on one IEC you double the rating.
Strange issue I observed today. Did not do any troubleshooting yet, but might be you already experienced with such thing...
I hear high pitch noise (7-10 kHz -> by my ear) with pups when I turn FSP during about first 15-20 min till it heats up. It is quite loud (at my listening level, and very pronounced in high volume) at the beginning and slowly dissolves till its completely disappears after FSP is at its temperature, in about 30 min.
No any degradation to the sound when I play my records after that. Still listening an amassing quality sound.
Any ideas or the way to troubleshoot it quickly?
I hear high pitch noise (7-10 kHz -> by my ear) with pups when I turn FSP during about first 15-20 min till it heats up. It is quite loud (at my listening level, and very pronounced in high volume) at the beginning and slowly dissolves till its completely disappears after FSP is at its temperature, in about 30 min.
No any degradation to the sound when I play my records after that. Still listening an amassing quality sound.
Any ideas or the way to troubleshoot it quickly?
Yes, I turned volume up on my preamp and switched ON PSU for FSP. This noise is disappeared in about 20-30 min. Then I stated to listen and it is sounds as it should. No any sign of sound quality degradation.
I'll check it out tomorrow and following day before opening boxes.
Weird, watch it to see if it repeats itself before we start speculating then. Also never turn on the source's PSU with open volume. You can turn volume up a little afterwards to watch for the mysterious noises. Source power on first, preamp second, power amp last, and opposite sequence for turn off. So to be safe from big transient noises. Wait for two seconds between each step.
You asked if something unusual happened and yes, after family "interrogation" I know that my son tried to listen records trough my other setup - solid state. So, I have B1 buffer with volume control and Nelson's F5Turbo.
So, my son accidentally connected FSP output to B1 output (instead of the input) for couple sec.
I'm not sure if that is related to my issue and can cause anything...
Sent from my iPhone using Tapatalk
So, my son accidentally connected FSP output to B1 output (instead of the input) for couple sec.
I'm not sure if that is related to my issue and can cause anything...
Sent from my iPhone using Tapatalk
