That’s very easy to test.
I will insert a 110R resistor in the 38R Cart’s line, increase gain by 12dB and see what happens.
You never know, but I would be surprised if anything unexpected happens.
Hans
Sorry my bad - 30 Ohms is correct.
Re high R carts in a trans impedance stage - no idea other than you would have to raise the TIS output load appropriately to get the required gain. There is a noise penalty of course with high R carts. The TIS stages like a Leach offer very low equivalent input noise of low single digit R easily swamped by cart R noise.
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Basically yes. Take for example my Ortofon Rohman. Strong magnet so gets 0.25mV from a 6Ohm air core. Operating into your transimpedance stage you would get a current, say Ia. If you rewind to 3 ohms, keeping the magnet system the same then will current (say Ib) be close to the same? If it is then the required gain will also be the same, unless I have completely missed something as usual.
Then repeat until something reaches a limit.
Then repeat until something reaches a limit.
Oh and for fans of doing things slow time. John Cage: Crowds flock to hear song change chord for first time in seven years - BBC News
Interesting question.
So you say that the produced voltage is directly proportional to the impedance with a given set of magnets, causing that the produced current and gain will remain the same because of that.
And yes, a 1R 0.1mV Cart will theoretically give the same gain as a 5R 0.5mV cart when using a transimpedance amp, whereas a voltage amp will show a factor 5 difference in output voltage.
How far you can go in both directions depends on several factors like input impedance of the current input and the rest of the chain, input noise etc, etc.
This seems what Ortofon has done with their low output options, lower voltage and lower impedance for which a low input impedance amp will be favourable.
Hans
So you say that the produced voltage is directly proportional to the impedance with a given set of magnets, causing that the produced current and gain will remain the same because of that.
And yes, a 1R 0.1mV Cart will theoretically give the same gain as a 5R 0.5mV cart when using a transimpedance amp, whereas a voltage amp will show a factor 5 difference in output voltage.
How far you can go in both directions depends on several factors like input impedance of the current input and the rest of the chain, input noise etc, etc.
This seems what Ortofon has done with their low output options, lower voltage and lower impedance for which a low input impedance amp will be favourable.
Hans
Here is essentially a 1 turn phono cartridge: https://worldradiohistory.com/hd2/I...o-IDX/IDX/70s/Audio-1979-06-OCR-Page-0066.pdf 3 Ohms and .04 mV.
One key difference is that the low Z load makes the internal inductance a part of the circuit. That leads to two questions- first, where is the pole landing? And once you pull current through the magnetics will their nonlinearity show in the output? You could test for these using a really low source Z and put the cartridge in series with the input.
One key difference is that the low Z load makes the internal inductance a part of the circuit. That leads to two questions- first, where is the pole landing? And once you pull current through the magnetics will their nonlinearity show in the output? You could test for these using a really low source Z and put the cartridge in series with the input.
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Yes, and the SNR is the same, so essentially there is no noise penalty for increasing the impedance.
Benz Micro is doing a range of MC cartridges in low, medium and high output. I suspect only the coils are different, since all three models gave almost exactly the same output using a transimpedance stage (mine). A voltage gain stage was of course providing different output levels, but the SNR was also preserved. So for a voltage gain stage, choosing one of the 3 BM models is only a matter of the existing preamp nominal input level, the HL models could easily feed directly a MM stage since they have up to 2.5mV output. Benz Micro was careful enough to make sure that the HL models inductance did not make a pole within the audio frequencies range, the inductances are usually less than 100uH.
Ok, I'll bite. What's new in audio in the past 30 years?
Hey John, great to see you !!11!1!
So, wadda ya think of the ol' console tube radio; did you have one like it?
Well, I've been away for awhile and I have no sticks in any current fires ... so ...
shoot
In a paragraph you should be able to at least ... get my attention; I'm no full-on EE like you guys, and I haven't been diying in awhile (sigh), but ... I've been listening all these years so ...
What's new in audio?
Cheers :0
PS I actually came out and asked a few years ago, ... how would you update the BT (or any Curl design) for EMC/EMI input and output today (cells everywhere). That seems like a natural first-step to any update ...
Hey John, great to see you !!11!1!
So, wadda ya think of the ol' console tube radio; did you have one like it?
Well, I've been away for awhile and I have no sticks in any current fires ... so ...
shoot
In a paragraph you should be able to at least ... get my attention; I'm no full-on EE like you guys, and I haven't been diying in awhile (sigh), but ... I've been listening all these years so ...
What's new in audio?
Cheers :0
PS I actually came out and asked a few years ago, ... how would you update the BT (or any Curl design) for EMC/EMI input and output today (cells everywhere). That seems like a natural first-step to any update ...
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The Ebony H has a 25 times higher output with an Impedance that’s 90 times higher as the Ebony TR.
They must have used thinner wire for the coil to keep the mass low.
Searching the internet, I was surprised to find how many TRs have been sold second hand.
They are offered for between $1000,- and $1300,-.
Hans
How about Class A all the way to the speaker VC? Build the speaker with a non-centered VC and biased suspension (like one that's sat horizontally for a few too many years). Use an - of course - adjustable DC current to pull (or push) it back into proper position. Have the audio ride on top of this current.
I can see audiophiles with their calipers now; "Just 1mm off and I can hear the difference".
I can see audiophiles with their calipers now; "Just 1mm off and I can hear the difference".