BillFitzmaurice.info

I have yet to build a BFM speaker. But am planning on doing so in the near future. I happened to come upon a Mackie FR-2500 amplifier. What do you guys know of it and would it be a good amp for sub use? I am wondering if stereo would work well, or if i would want to put into bridge mode. Thank you.

I believe Bill does not recommend using amplifiers in bridge mode due to excessive voltages that would be produced.

It could work. Run a pair of subs off of each channel. From the manual......

MONO: This mode is used when you want to send a mono signal to both outputs. It accepts a single input (INPUT 1), and routes it to both the CHANNEL 1 and CHANNEL 2 outputs.

It's not enough to run the 301xLF drivers to full capacity, but it will bring them close. At full power it draws 10 amps from the wall.

Just so you understand, Bridge and Mono are two separate things...sometimes manufacturers combine them into one by making output on only one channel( channel 1) in bridge mode, which would, by default, be a mono channel. If the amplifier is putting output to both channels 1 and 2, its not bridged, unless its normally a 4 channel amplifier.

Mono mode simply takes one input and outputs the same signal to two separate channels

To further answer your question, yes the amplifier should be in MONO mode to run both channels to a cluster of subs. However, make sure the one input to the amplifier has fully summed (from both stereo channels) bass signals going to it, or you will miss out on stereo bass content.

Bridge mode is normally not necessary except to run a large number of subs from one channel, or to run a small amplifier to a large sub (power handling wise)

ryan222h wrote:Bridge mode is normally not necessary except to run a large number of subs from one channel, or to run a small amplifier to a large sub (power handling wise)

You should only use an amp bridged if the voltage swing of it's single channel is insufficient.

Thank you all for the replies. I was just curious if an amp like this has had any responses for its instability over age. For instance are they a reliable amp and has anyone on here ever used one for their system. I have an IPR1600 and love it for it's weight, but am not able to afford an IPR 3000 yet. I do appreciate the information that everyone has given. It has come out to be quite useful.

I also have ipr1600 (dsp model) for my pair of T39's and its wonderful with its built in high and low pass filters, and has plenty of power for my needs. I can run the T39's each to one channel since mine about 3-4 ohm cabs. Also I have been just using the built in amplifier DDT as my limiter since the amp is slightly under-powered.

The peavey ipr dsp models really are a one-stop shop for bfm cabs provided you set them up correctly. Sorry I don't have any knowledge of Mackie amps...never really heard anything bad about them either, though.

I use the younger brother of the 2500, the m1400i. mine needs to be bridged, I can't imagine the 2500 needs to, iirc the 1400 puts out 38v per channel, the 2500 should have 55-60v guestimated. I haven't had any issues, in bridged mode it just idles along w/o much heat dissipation. it also has built in variable highpass and xover. other than weight it is a great amp.