I wasn’t able to find in specs, manual or forums. Does anyone know what, if any, the upper voltage limits are on the XLR and RCA inputs on the BHK Preamp?
John Atkinson did the measurements, I think it clips at 29V into 100k ohms.
PS Audio BHK Signature preamplifier Measurements | Stereophile.com
Thanks Serhan – I’m not sure how to interpret that.
He mentions output volume clips – but is he saying that an input volume of 29V balanced will cause clipping at the output with 100kohm load, or that the measured output volume is 29V when clipping occurs, but the input volume is unknown?
He usually responds to questions. It might be worth asking him.
He’s also still active on Audio Asylum in the Critics Corner section along with other reviewers
Why is this spec of interest? It is not something I have ever looked for.
That’s a tough one because of the input attenuator. You can input a LOT of voltage without bothering anything because the attenuator is before the vacuum tube. So, input something silly like 5 volts and it’s not a problem because there’s no input circuitry to upset.
I’ve read that some equipment can output up to 10v via RCA, so I was curious as I’ve only read most to output 4v. It seemed outlandishly high and got me thinking about the BHK Preamp’s limits.
10V would be incredibly high for a source to send to a preamp.
What have you seen which outputs 10V?
The Mola Mola Tambaqui outputs 6v (which the BHK handles just fine) at its maximum setting… anything higher than that would be unusual.
I have the Stellar Phono Preamp, and it can and will output a whopping 24v. I have it feeding a Krell K-300i right now, and I have to lower the input impedance on my cartridge from 47kΩ to 100Ω to stop it from clipping the Krell, which overloads at 10.4V RMS in balanced, and the phono amp outputs 2.4x more voltage than that!
Welcome, @john.margaglione !