Request...Phono preamp subsonic rumble filter

[jerseyplumber]

I think a software revision should include the ability to create a subsonic rumble filter built into the phono preamp. It could possibly be simple considering the eq. ability built into all inputs. I think a simple button style activation set up for the phono preamp section would help to push your product further up into that audiophile acceptable realm and go a long way with vinyl listeners who use your phono preamp. Otherwise I need a separate phono preamp that includes one, or I have to readjust my equalizer settings each time to play vinyl. If I'm missing a feature that can stay preset for phono input without losing subsonic range while playing digital media please chime in with a simple solution. Thanks in advance.

 

[hgo58]

I think a software revision should include the ability to create a subsonic rumble filter built into the phono preamp. It could possibly be simple considering the eq. ability built into all outputs. I think a simple button style activation set up for the phono preamp section would help to push your product further up into that audiophile acceptable realm and go a long way with vinyl listeners who use your phono preamp. Otherwise I need a separate phono preamp that includes one, or I have to readjust my equalizer settings each time to play vinyl. If I'm missing a feature that can stay preset for phono input without losing subsonic range while playing digital media please chime in with a simple solution. Thanks in advance.

The EQ is per input, not per output. So you can set a specific EQ for the phono input.

If the current EQ can be used as as a rumble filter is another question. A PEQ high-pass filter at 50 Hz may do it?

 

[jerseyplumber]

Agreed. The eq bottom slider is at 80hz which will certainly effect normal low frequency sound. maybe another slider at 50 Hz might do it. I could flatten out or reduce below flat the below 50 Hz adjustment and eliminate the rumble. Thanks for the correction . I will revise my post.

 

[hgo58]

Agreed. The eq bottom slider is at 80hz which will certainly effect normal low frequency sound. maybe another slider at 50 Hz might do it. I could flatten out or reduce below flat the below 50 Hz adjustment and eliminate the rumble. Thanks for the correction . I will revise my post.

Like this?

 

[slartibartfast]

I think a software revision should include the ability to create a subsonic rumble filter built into the phono preamp. It could possibly be simple considering the eq. ability built into all inputs. I think a simple button style activation set up for the phono preamp section would help to push your product further up into that audiophile acceptable realm and go a long way with vinyl listeners who use your phono preamp. Otherwise I need a separate phono preamp that includes one, or I have to readjust my equalizer settings each time to play vinyl. If I'm missing a feature that can stay preset for phono input without losing subsonic range while playing digital media please chime in with a simple solution. Thanks in advance.

There are many phono preamps that don't have rumble filters. None of my integrated amps or phono preamps have had them. It would be a useful option though.

 

[QuarryHunslet]

There are many phono preamps that don't have rumble filters. None of my integrated amps or phono preamps have had them. It would be a useful option though.

I think the last time I saw a Rumble filter was on an Amstrad amplifier back in the 1970’s, I have never had the need to use one in over 50 years, and around 10 turntables that I have owned in that time.

 

[harkpabst]

I always thought that there is a rumble filter already ... but maybe I just never checked this.

50 Hz is a bit much, though, for my taste. Something like HP 32 Hz Q=0,71 should be sufficient. That would be 24 dB down at 8 Hz.

 

[harkpabst]

I think the last time I saw a Rumble filter was on an Amstrad amplifier back in the 1970’s, I have never had the need to use one in over 50 years, and around 10 turntables that I have owned in that time.

Are you sure that there's never been a rumble filter or just no switchable rumble filter? All classic Quad amps, to name just one example, did have fixed rumble filters.

 

[slartibartfast]

I think the last time I saw a Rumble filter was on an Amstrad amplifier back in the 1970’s, I have never had the need to use one in over 50 years, and around 10 turntables that I have owned in that time.

I think they are only useful if your records are extremely warped and your amp has a frequency response below 10Hz

 

[QuarryHunslet]

Are you sure that there's never been a rumble filter or just no switchable rumble filter? All classic Quad amps, to name just one example, did have fixed rumble filters.

Certainly none that I have ever been aware of. I still have a Quad 44, fitted with a moving coil board for my Linn LP12, but I’m unaware of any rumble filter, there’s certainly no switch for one.

 

[slartibartfast]

Are you sure that there's never been a rumble filter or just no switchable rumble filter? All classic Quad amps, to name just one example, did have fixed rumble filters.

When I do vinyl rips I always see the tonearm resonance at around 10Hz so presumably no rumble filter.

 

[harkpabst]

Certainly none that I have ever been aware of. I still have a Quad 44, fitted with a moving coil board for my Linn LP12, but I’m unaware of any rumble filter, there’s certainly no switch for one.

Exactly what I meant to say, the rumble filter is fixed, non-switchable.

At least for the 34 I know for sure that the rumble filter is not even part of the phono card, it's on the amplifier board itself (but just for the phono input). I'd be surprised if this was not the same with the 44.

 

[QuarryHunslet]

Exactly what I meant to say, the rumble filter is fixed, non-switchable.

At least for the 34 I know for sure that the rumble filter is not even part of the phono card, it's on the amplifier board itself (but just for the phono input). I'd be surprised if this was not the same with the 44.

I will have to see if I can find any information about this online.

 

[harkpabst]

I just checked the schematics and the Quad 44 has the rumble filter (really just a 2.2 µF capacitor in series and 6.8 kOhm resistor following in parallel) right on the disc module.

It's not a very steep filter, but it's still a rumble filter.

 

[QuarryHunslet]

I just checked the schematics and the Quad 44 has the rumble filter (really just a 2.2 µF capacitor in series and 6.8 kOhm resistor following in parallel) right on the disc module.

It's not a very steep filter, but it's still a rumble filter.

Would this be mentioned in the manual, as I have that.

 

[harkpabst]

Would this be mentioned in the manual, as I have that.

No, this information is not included in the two versions of the "Instruction Book" I own, but it's explicitly mentioned in the attached brochure.