More amp headroom with HPF (Fdeck or Thumpinator)

[GK Breivik]

I was wondering if anybody who has used either the Fdeck HPF or the sfx Thumpinator could share their experiences with regards to amp headroom.

My amp runs out of steam before my cabinets, and I’m wondering if I could expect an appreciable volume increase if I hi-passed at 30 or 35. This is a Thunderfunk TFB-750 into an eight ohm load, if it helps.

 

[Downunderwonder]

Running out of amp with 750w at 4ohm doesn't sound likely. What cab?

HPF-3 is the weapon of choice for curbing unwanted fundamentals or tightening up room response.

 

[mrmills]

Removing very low frequency content will help as it is wasted energy if the speaker is not responsive at that frequency. How much it will help really does depend.

Question is, how much being sent to the speakers below 35Hz? You can only really tell with a signal generator and frequency analysis of the amplifiers output.

Remember that a a doubling in volume requires a squaring of power so a few extra Watts will make little difference.

 

[GK Breivik]

@Downunderwoofer: This is an 8 ohm cab, so I think the amp puts out 400 W.
@mrmills: I understand about the volume/ watts relationship. OTOH, low frequencies need more power than higher frequencies too.

I seem to remember that people claim increased headroom with an external hpf, so I’m looking for real world user experiences.

 

[jnewmark]

Some bass amps already have a built in high pass filter. Does your manual state anything about it ?

 

[mjmeche]

the fdeck does tighten up low end. I will find out this weekend when i use it with my headlite and schroder cab which tends to fart out on low end.

 

[GK Breivik]

The amp probably has a filter way down low, to filter out the infrasonics at least. he manual doesn’t say. My streamliner 900 feels a little louder thru the same cabs, and that one has a hpf @ 35 IIRC.

 

[dincz]

" Remember that a a doubling in volume requires a squaring of power so a few extra Watts will make little difference."

There's no need to exaggerate!