How best to drive RS 2.5's

Ricm

New Member
Please check out my posting in the Marantz forum. I am torn on what to do with these excellent speakers. The thread is titled "I feel small when compared to you all."

In this (The Infinity) forum I was inquiring on their worth. Since I have learned that they are (only) worth $600.00, I am now considering how best to use them. In the Marantz forum I am questioning how to drive them.
 
Ricm said:
Since I have learned that they are (only) worth $600.00, I am now considering how best to use them. In the Marantz forum I am questioning how to drive them.

Ricm,

I'm not sure what your question is on "how best to use them".

They're great speakers, but need a decent amount of power. You indicated in the Marantz forum you were using a Carver M200 to drive them. At 120 watts (I believe) into 8 ohms, you could probably do with a bit more power. Since I don't believe you have the active crossover, you might try getting another M200 and vertically bi-amping them.

If you could give us a little more info on your question/concerns, I am sure the folks here could provide plenty of advice.

David
 
phaedrus said:
Ricm,

I'm not sure what your question is on "how best to use them".

They're great speakers, but need a decent amount of power. You indicated in the Marantz forum you were using a Carver M200 to drive them. At 120 watts (I believe) into 8 ohms, you could probably do with a bit more power. Since I don't believe you have the active crossover, you might try getting another M200 and vertically bi-amping them.

If you could give us a little more info on your question/concerns, I am sure the folks here could provide plenty of advice.

David

When I said "Use" them, I guess I ment "drive" them. Since I have never used any other amp to drive them, I guess I was questioning the Marantz/Carver combination.

I have never considered that they may need more power. At 50% volume the 2.5's are plenty loud. Crystal clear, but loud.

I actually have a twin M400 (I miss-spoke when I said M200). I can try using one per channel and see if it changes anything.

Should I be concerned that I may damage speakers with too much power? If I understand the Carvers correctly, I am now pushing about 200 watts per channel. If I use one Carver per speaker I think I will be pushing 400 per channel.
 
I've got a pair and they do need lots of juice. My hope is to get a Sony TA-N80ES. With 270 wpc at 4 ohm, a cost-effective market price, and the Sony house sound, they should be the ticket.

Not to say other amps or pair of amps wouldn't work either. Right now, I've got a McIntosh MC2105 at 105 wpc - adequate but more would be better. I might add a 50 wpc MC250 for the top-end in a bi-amp arrangement.

I do fear that enough tube power for these would be expensive.
 
Ricm
If your traveling south in the future and you want to hear a pair of 2.5's bi-amped, drop me a line and if timing works you can give my setup a listen.:thmbsp:
 
Army said:
Ricm
If your traveling south in the future and you want to hear a pair of 2.5's bi-amped, drop me a line and if timing works you can give my setup a listen.:thmbsp:

Thanks for the offer!

Did you ever find a cross over or are you runniing the ribbons and woof separatly? Do you run them both at the same wattage?

I actually have a 2nd carver M400, but have never concidered running both in a biamp configuration. With just one amp the speakers are very loud, but still crystal clear. Is there a danger of damaging something with too much power? As a sterio amp the carver supplies 200 wpc. As a standalone, I figure it must push 400 wpc.
 
No I didn't find an external xover. I'm using the internal switched to bi-amp and I doubt I'll spend the extra cashola to buy an external. I don't want to change a thing, I think they sound better bi-amped!

I'm running two power amps that are rated at 250 wpc in 8Ω switched to 4Ω side. Not sure how many wpc but a rough guess would be over 400 wpc each. Thats what I had and they look pretty good stacked :)

Can too power be a problem, yes and no. Yes if someone takes the volume to insane stupid db levels you can melt voice coils in the woofers and deafen your neighbors. I've cranked this system up pretty loud, hitting peaks of 100 wpc on the meters and barely could stand how loud it was for a short time :D

More clean power tends to make the woofers behave better IMO. I have also noticed the sound seems richer as well as cleaner in the midrange and low end.

If you want to try bi-amping all you would need is a couple of rca adapters that "Y" from the 2230 pre-amp out to each power amp and remove the speaker jumpers and switch your speakers to bi-amp.

You should be good to go :thmbsp:
 
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The question that still bedevils me is what is the proper power relationship between amps.

I've got two choices. the first is a pair of McIntosh amps with autoformers at 105 wpc for the bass and 50 wpc for the mid/tweeters.

Alternately, I could go 270 wpc at 4 ohm on the bass from a Sony and 105 wpc from the McIntosh.

Down the road, would the 270 wpc Sony and a 30 wpc tube amp work?

The mids and tweeters demain much less power than the woofer but where does it get unbalanced?
 
Whitehall
I'm no expert, but I did happen to bend EW's ear and asked what he thought about running the top end with a 30 watt tube amp.

And he wasn't sure, but had a good suggestion. Try running a 30 wpc amp (any SS) amp which are much cheaper than tube amps and see how it works out.
And seeing as you have a 50wpc Mac you could start there with the Sony running the bottom end to see how that sounds, just a thought.

Or if totem checks back in he could lend an opinion or two, the voice of tube experience with infinities :thmbsp:
 
Ultimately, experimentation rules.

I just like a better idea of what I'm getting into before I connect my expensive amps to my exotic and irreplacable speakers.
 
I am of the same mind, (re experimentation) Just did a tryout last night and was not happy at all with the results. Highs-mids ok but bass was just thin sounding.
Changed pre amps & things where better but far from what I want. Next I moved
the speaker location and did find the lower end a little better. I think the biggest problem is still AMPLIFICATION!! I went into this knowing that it was an issue
to be dealt with, but I must say my patience is growing thin.
 
for lows end try an arcus A250

totem said:
I am of the same mind, (re experimentation) Just did a tryout last night and was not happy at all with the results. Highs-mids ok but bass was just thin sounding.
Changed pre amps & things where better but far from what I want. Next I moved
the speaker location and did find the lower end a little better. I think the biggest problem is still AMPLIFICATION!! I went into this knowing that it was an issue
to be dealt with, but I must say my patience is growing thin.
Amp . cheap on ebay 200/watts @ 8 ohms, 350 @4 ohms, where I believe the
2.5 are . this amp works great on my RSIIs which I know are not even close to the 2.5 , but they sound better on a higher wattage amp even though your drive them are low volume levels..RS ll s are 4ohm speakers.
 
Army,

I looked at this one too but realized that the unit has only balanced inputs and outputs. Unless one has balanced preamp and amp connections, this one would be a pain.

Also it has 18 dB (third order) crossover slopes. I'd think a 12 dB slope would be my preference.

I'm looking also for an active crossover for the Rectilinear IIIs I just got from OnePixel.

The crossovers from the "cars that go boom" crowd uses look attractive to me. The Lanzar has 12 dB slopes, three levels output plus subwoofer and subwoofer boast with variable Q. One needs a separate 14.4 v DC power supply. The man-machine interface is not as good - that's a downside.
 
If you went for the digital Behringer, you can choose whatever slope you want, including the 6db slope of the original Infinity electronic crossover.
 
Nope I couldn't afford the digi Behringer, but I think this one will work fine. Set the crossover points as close as I can and let the passive pick up a tad if needed. :thmbsp:

The balanced inputs did cost a few bucks to adapt to rca :yes:
 
How does one convert XLR to RCA and vice versa?

Didn't know one could do that without op amps or differential amps.
 
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