Going back to what I asked.
-10dBV is 316mVac
If maximum output is 11Vpk = 7.778Vac.
This should be the maximum unclipped output from the RIAA stage+Buffer.
The overhead would be 7.778/0.316 = +28dB ref -10dBV
Is that correct?
-10dBV is 316mVac
If maximum output is 11Vpk = 7.778Vac.
This should be the maximum unclipped output from the RIAA stage+Buffer.
The overhead would be 7.778/0.316 = +28dB ref -10dBV
Is that correct?
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This is correct for say MC builds ending with 34.5V-35V regulated supply rail after trimming for TP1-TP2. Others will end up with 36V-37V even, so there is a bit more swing space to them
Nominal is at 0dB record modulation. Average is at each record's dynamic median. Not all cuts are equal. A 45RPM EP will be +6dB on average than a 33RPM LP for instance
OK, I'll try again.
If nominal equals 0dB record modulation, then the question becomes:
What is 0dB record modulation?
What is 0dB referred to?
Remember that the Bell and the decibel are RATIOS.
If nominal equals 0dB record modulation, then the question becomes:
What is 0dB record modulation?
What is 0dB referred to?
Remember that the Bell and the decibel are RATIOS.
Finally !
But why do you make it so difficult by referring to 0dB when you really meant to refer to 5cm/s?
0dB tells us nothing without a reference value!
But why do you make it so difficult by referring to 0dB when you really meant to refer to 5cm/s?
0dB tells us nothing without a reference value!
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That is groove modulation that translates into voltage output by the cartridge. A cartridge is characterized at 5 cm/s millivolt nominal output and this is our base for characterizing our voltage gain circuit i.e. the FSP in this case. So its FSP output relative to cartridge output and dB is good for expressing relative voltages.
That's fine. I have no problem with that explanation and method.
It's your un-referenced 0dB that told us nothing.
Transformers
Hi I need some advice ,I have built my raw psu and Salas njfet phono I have taken great care and followed the guide
I have 2 transformers make vigortronix 2x 18 30va .if I join two wires together I make 44 vac for each (not sure what you call this) if I then join transformers to raw psu I make 58vdc each side .
This sounds far to much volts I last thing I want to do is damage the phono. is this ok or not thanks john
Hi I need some advice ,I have built my raw psu and Salas njfet phono I have taken great care and followed the guide
I have 2 transformers make vigortronix 2x 18 30va .if I join two wires together I make 44 vac for each (not sure what you call this) if I then join transformers to raw psu I make 58vdc each side .
This sounds far to much volts I last thing I want to do is damage the phono. is this ok or not thanks john
Guys, the specs i posted are from the new 2015 type cartridge.... Mine does 4 mV maximum. What should the values be to get the best gain number without problems?
Thanks!
Thanks!
Could draw pics of how you made the connections for the two arrangements and post photo of your pics here?
58V can damage the phono's on-board regs. I suggest you use 470 Ohm 10W dummy load resistors to load each RAW PSU board's output so to measure VDC while the transformers are comparably loaded to final phono loading.
If it is more than 50V put 20 Ohm 5W RD/LINK resistors on the RAW board designated places to drop the VDC. Remeasure while on dummy loads. If VDC has dropped enough (at 45V-50V), power off & disconnect the dummy resistors. Its modified & tested now for proper RAW DC voltage level when the real phono channels will get connected to it.
Salas: Do I have to populatie R4 with 1.8K? It is a MM(MI) cartridge.
Is 1.2K good for R4? (I have already put 1.2K in 🙂 )
Is 1.2K good for R4? (I have already put 1.2K in 🙂 )
Grado
Haha, It's a grado prestige red.... not the latest model but the 2014 model. It says it's MI..... should be something like MM.
Haha, It's a grado prestige red.... not the latest model but the 2014 model. It says it's MI..... should be something like MM.