Low wattage Sub recommendations?

[Nickg0523]

I have a dual output 25 watt amp running a Dayton rs100-8 and I'm looking to get a sub. I've looked around and can't find any subs that are around the amp's wattage. Any recommendations on drivers? I know I would need a crossover at some point...

 

[W0J0]

Are you trying to drive the subs and your full range speakers with the same amp channels simultaneously? If you are, it's not the best idea but your goal will be to find sub drivers with similar sensitivity as your full rangers. This way you'll have less amp power wasted as heat from resistors in your passive crossover to attenuate one or the other driver. A better scenario would be to get an additional amp for your sub and use an active crossover to divide frequencies appropriate for each speaker and feed those signals to the separate amp channels driving each of them.

 

[Nickg0523]

Well I was hoping I could use the same amp with passive crossovers because I want to keep costs down. The amp I have no isn't all that great and I could maybe use a better one. How close should the sensitivities be?

 

[chris661]

Passive crossovers for subs are always a bad idea. I promise. The required components are huge and can work out much more expensive than a 2x50w amplifier, PSU, and line-level crossover.

Chris

 

[Nickg0523]

So if i were to get a 2x50 amp how easy would it be to blow the 30 watt rs100?

 

[turk 182]

you would not be running the RS100's on that amp it's intended to run the subs your thinking of adding.

 

[Nickg0523]

Oh yeah that was dumb... didn't think that through. How many decibels between sensitivities should they be? I've found several with differences of 4/5 decibels

 

[turk 182]

well with two amps you can vary the gain/volume to get a level match between the RS 100's and your new subs. so individual driver driver sensitivity is less critical with respect to matching.
you can change the levels between the hi(RS 100's) and the low(sub) ranges which is something you can't do with a passive crossover. (not to catch flak yes passive crossover levels are adjustable it's just not as easy)
after that there's the crossover to consider.

 

[Nickg0523]

I have just started working with speakers a month or two ago and this is my first venture into crossovers... where are places I can find active crossovers for cheap? I see that they have them on parts express and on amazon but they are extremely expensive.

 

[straight8s]

If you can find a Paradigm x30 used they are low cost crossovers, and decent. Or an NHT amp with built in crossover, I seen them for as little as 50 dollars used.

 

[Nickg0523]

Would something like this work? Lepai LP-168HA 2.1 2x40W Mini Amplifier + 1x68W Sub Output It says it has a dedicated subwoofer output

 

[Nickg0523]

Amazon.com: ONEU Audio Amplifier, Separated Subwoofer Volume Controlled Stereo Amplifier 2 x 45-Watt and 1x68W Sub Output, Super Bass 2.1 Channel Audio Power Amplifier with Power Supply: Electronics I found this one too. Looks similar. This amp for both the rs100 and the sub. Replacing the junky Bluetooth amp

 

[turk 182]

either of those would work.(not that i looked that hard but they appear to be the same amp)

 

[Nickg0523]

If I were to add a tweeter in the future could I use a passive crossover?

 

[Nickg0523]

I mean use a Passive crossover and only use the tweeter output and leave the woofer one empty

 

[W0J0]

I mean use a Passive crossover and only use the tweeter output and leave the woofer one empty

No, you don't do that. Your active crossover will separate the subs from the full range. The passive crossover will separate the lows/mids from the highs. You don't want the woofer/midrange going into the range of the tweeter if you have a tweeter. That will lead to weird phase issues.
Do yourself a favor and do some reading on speaker and crossover design.