Ferrum Audio thread, Hypsos / Oor / Erco

If you try to make sense out of it with numbers and voltages it becomes really difficult to known what sound your getting into.

This is what I guide myself with:

-dacs usually include their own preamp
-you dont wanna have that many pres on a chain as it raises distorsion
-good preamps are very expensive, and the ones from headamps are usually not amazing.

Havent heard v281 sounds like you really like it

A good preamp
-doesnt come by easily, theyre expensive.
-will give a different presentation than standard, often with better or different instrument separation and position.
-It lets you hear things you could hear before so easily
-some pres try to preserve the original sound as much as possible, while others try to give a new coat of paint, some in the middle.

I don’t know the answer to your questions, but I have more answers for you, LOL.

How is the OOR in bypass mode with the Wandla as a preamp? I heard it’s supposed to be the best way to run the Wandla+OOR. Also, how is the Wandla+v281? That was my goal, but I went a different route.

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Perhaps surprisingly while this is considered normal for output levels, but most amps have significantly higher input sensitivity that that, it’s not unusual for an amp to have 1V or even < 0.5v input sensitivity.
The amps can clip with high input signals, but in practice it’ll only be at the last 10% of the volume pot, and for whatever illogical reason people don’t like turning volume pots past 50% which is about 10%-20% of the total input voltage,
It’s worth noting that the 2.2V is the peak of a maximum volume sine wave, and most recorded music (even the loudness wars stuff) doesn’t average close to that.

But even if the sensitivity was 2.2V you’d only see that with the volume control at the maximum position, if the source was actually putting that out, otherwise it’s attenuating the input signal by a lot.

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That is the thing though, i am surprised by the fact that the OOR will not clip with a MUCH higher input signal, i would expect to see an amp clip way before noon in the volume pot if being fed 10V.

It looks like the OOR was actually designed to work with a much higher signal than other amps.

I actually don’t owna a WANDLA, i tried to use the v281 as pre because i read that the WANDLA has a 12V output signal, and my Gungnir “only” outputs 4V via XLR.

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Noon is like 10% of the input, so ~1V with 10V in, and as I said the signal will be less than that probably closer to 300mV RMS on average.
At 3 o’clock volume your still at probably 25% of the input voltage.

As I pointed out in more detail in another thread Volume pots are not linear. Volume Pots are not Linear

The input sensitivity is a function of the amplifiers gain, any overhead the circuit needs and the power supply rail.
It’s mostly moot anyway, 7v sounds like a lot more than 2.2V, but it’s only about 7dB’s.

It looks like the input sensitivity of the Orr is 4V RMS, that’s pretty high, would require an ~11V PK2PK input signal to clip.

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