Adding bass tone control between my amp and RS2.5

Oneoff

Active Member
Hello everyone!
So I acquired a pair of Infinity RS2.5 about a week ago, and also a Musical Fidelity A5 from bartertown (Thanks Matt).
The A5 delivers 400wpc at 4ohms quietly and without much of a sweat. The sound on the mid/ high frequencies is just amazing, I seriously never heard anything like that before. The low end section is ok. I usually like it more punchy and i know these woofers can deliver that after using my sansui receiver as a pre and boosting up the bass tone control a little.
The A5 integrated doesn’t have any tone controls.
The question is- how do I add a simple bass tone control?
The problem(s) - i don’t want to add any noise
to the system (the A5 is dead quiet), and I don’t want to lose the A5 pre section (with it’s nice phono stage, remote etc.) by adding another external preamp just for the bass control...

Does the original external crossover can take care of the above? I’m not too familiar with it’s abilities...

Is there anything out there to add between the amp’s speakers terminals and the speakers? (Probably not...)

Are there any other simple and low cost solutions you can think of for bass improvement?

I’m assuming this is not a matter of (lacking) power because when I connected the amp to the the ‘low’ terminals only on the RS, the bass was just the same. I guess, if 400w is not enough to drive only the woofers, I’m in trouble here...

I currently don’t want to sell the speakers nor the amp...

Thanks in advance for your input!
 
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You are right about the mids/highs on the 2.5 being amazing, however I find the bass to be well balanced and clean on mine set.
This isn't a particularly bass heavy example and I suppose listening by way of anything other than a stereo system would not portray much bass.
 
I would think on the cheap you could add or remove stuffing in the bass cabinet and see if you can hit your goal there, surprised though because usually the bass in the 2.5 is very good.

Tubed those look really nice !
 
You are right about the mids/highs on the 2.5 being amazing, however I find the bass to be well balanced and clean on mine set.
This isn't a particularly bass heavy example and I suppose listening by way of anything other than a stereo system would not portray much bass.
I think that mine sounds very similar, it’s a little hard to know for sure by the video. Still i’d Love to have some option to tweek it up a bit.

Btw-what power amp are you using with them?
 
I would think on the cheap you could add or remove stuffing in the bass cabinet and see if you can hit your goal there, surprised though because usually the bass in the 2.5 is very good.

Tubed those look really nice !
Thanks, I thought about that but I might want
To have more +\- Control over the low end.
 
Btw- not sure if this might effect anything ,
But I added some stick on ‘slider pads’ on the bottom of the speaker in order to move them
more easily on the hardwood floors.
These are made of hard foam with some sliding material underneath.
 
You may want to replace the electrolytic capacitors.
They become bad or weak depending upon use and time causing output to diminish.
Also bi amplification with variable output controls allow for an increase or decrease between bass and upper frequency , so of like room EQ and or taste.
I use a Yamaha M-85/C-85 to power and find no need of biamping. 260 watts per
Have fun
 
Btw- not sure if this might effect anything ,
But I added some stick on ‘slider pads’ on the bottom of the speaker in order to move them
more easily on the hardwood floors.
These are made of hard foam with some sliding material underneath.
Shouldn't affect anything.
Try a few feet off the back and side walls, perhaps the reflections are a bit much and unbalancing the bass:dunno:
 
My 2.5s have plenty of bass and I have no tone controls. Check the electrolytic caps and see if they're good and in spec. I have the original woofer caps in mine, but they test out fine. You might re-flow the solder joints on the woofer circuit and make sure there is a good mechanical connection where metal is crimped down to metal on all the solder joints. Infinity had a bad habit of just sticking a wire through a capacitor's connection and letting the solder be the electrical connection without crimping the wire down to the tab. Solder should just be a seal of an already metal to metal connection.

Larry D.
 
My 2.5s have plenty of bass and I have no tone controls. Check the electrolytic caps and see if they're good and in spec. I have the original woofer caps in mine, but they test out fine. You might re-flow the solder joints on the woofer circuit and make sure there is a good mechanical connection where metal is crimped down to metal on all the solder joints. Infinity had a bad habit of just sticking a wire through a capacitor's connection and letting the solder be the electrical connection without crimping the wire down to the tab. Solder should just be a seal of an already metal to metal connection.

Larry D.
The crossovers looks like someone ‘was there’
before. Not sure. Some double stacked capacitors glued with hot glue to the baffle.
i guess I’ll need to check all the caps, solder joints and the schematics. There are some odd numbers of capacitance in case I’ll need something, and if I’m not wrong the caps are non polarized? I’m not gonna replace the large caps anyway. But thanks, I’ll check solder joints first...
 
i just took a look at your A5 and I wonder if it's up to the task, the pair that just found my home were tested with a Crown 1502 & Krell KSA-80, both produced house shaking bass at medium levels. The Watkins woofers in these speakers really like the current.

I'm always learning and maybe that 400 watts @ 4 ohms is just breakast for them, wakes them up and gets them going now they're looking for the that lunch that carries them thru the day.
 
i just took a look at your A5 and I wonder if it's up to the task, the pair that just found my home were tested with a Crown 1502 & Krell KSA-80, both produced house shaking bass at medium levels. The Watkins woofers in these speakers really like the current.

I'm always learning and maybe that 400 watts @ 4 ohms is just breakast for them, wakes them up and gets them going now they're looking for the that lunch that carries them thru the day.
Who knows, you might be right. the RS2.5 are rated 100W-300W for the whole bunch... but hey...
In this case there will be some kind of a compromise. I might add a Xls1502 for the woofers, or a simple active tone control, because it was tested and was really working..
 
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Have you done a listening study based on how far you sit from the speakers and where they are placed in the room? I haven't added bass traps and may never do it but one thing is for certain, there is a bass cancellation node in my room. I typically sit 9 - 11 feet away and the bass is excellent with the RSMs and the RS-1.5s. Get about 8 feet or closer and the bass drops off a cliff.
 
Have you tried turning the tweeters and mids down?

Have you heard good bass in that room, the room has a huge effect on bass response.

These speakers can be bi amped, maybe a second amp with a volume control so you could turn the woofers up...
 
Have you done a listening study based on how far you sit from the speakers and where they are placed in the room? I haven't added bass traps and may never do it but one thing is for certain, there is a bass cancellation node in my room. I typically sit 9 - 11 feet away and the bass is excellent with the RSMs and the RS-1.5s. Get about 8 feet or closer and the bass drops off a cliff.
I haven’t been looking too much into placement and room treatment (yet). The speakers are standing right where my old jbl used to be. Never had any issues with bass, actually I used to have too much...
 
Have you tried turning the tweeters and mids down?

Have you heard good bass in that room, the room has a huge effect on bass response.

These speakers can be bi amped, maybe a second amp with a volume control so you could turn the woofers up...

I’ve tried to turn all mids and highs down,
I also connected the amp only to the woofers..
There wasn’t any significant change.
yes I did have a Great Bass in that room, and with a relatively small jbls.
 
I’ve tried to turn all mids and highs down,
I also connected the amp only to the woofers..
There wasn’t any significant change.
yes I did have a Great Bass in that room, and with a relatively small jbls.
I should have mentioned right off the top to insure that your speakers are wired correctly, at the terminals and or the woofers.
They were likely taken out and rewired incorrectly.
 
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I should have mentioned right off the top to insure that your speakers are wired correctly, at the terminals and or the woofers.
They were likely taken out and rewired incorrectly.
What I meant is that there is no real change with the low frequency...
But wrong wiring- that’s what I’m afraid of. That’s quite a lot to investigate in that nest :)
BTW- How do you access the wires side of terminals on the back?
 
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