Advice needed- Ads 910l VS infinity RS 2.5 VS klipsch forte I

Do the Infinity 2.5 need an external crossover like the RS IIa/b? If so, does it come with the speakers?

Just my opinion, but I don't find my Infinity speakers lacking at all in the bass department (RS II, RS IIIa and RS 5b). It's tight bass, not boomy. My Kappa 7.1 S2 I would even call bass heavy.
 
Do the Infinity 2.5 need an external crossover like the RS IIa/b? If so, does it come with the speakers?

Just my opinion, but I don't find my Infinity speakers lacking at all in the bass department (RS II, RS IIIa and RS 5b). It's tight bass, not boomy. My Kappa 7.1 S2 I would even call bass heavy.
No, this pair doesn’t include a separate crossover. It has one onboard.
 
Do the Infinity 2.5 need an external crossover like the RS IIa/b? If so, does it come with the speakers?

Just my opinion, but I don't find my Infinity speakers lacking at all in the bass department (RS II, RS IIIa and RS 5b). It's tight bass, not boomy. My Kappa 7.1 S2 I would even call bass heavy.
The external electronic device that goes with the RS-IIa/b is a bass equalizer, not a crossover.
 
To clarify a factory EQ was available for the 2.5's

The EQ for the RS 2.5 was an option, where as for the RS 4.5 it was supplied as standard eq.
 
Yes, I do like a good clean, punchy and effortless bass like that L200 has. I usually don’t listen in a dance partys volume but I tend to prefer a sturdy and not too rare equipment that uses some exotic parts. Well, unless it’s sound quality Is ‘something else’...
I mean- what will happen when one day these rare EMIMs and EMITs drivers disappear from
eBay ?... these servo woofers are totally
Rare these days afaik.
I got the option to bi amp these RS 2.5
With two NAD 2100 which goes to 250WPC at 4ohms. The price would be the same when compared to this Adcom GFA-555. ($400).
The NAD are from a stereo shop so they are tested in a good condition.

Otherwise I’m staying with my 9090db, and gonna find me some big JBLs :)

Looking forward to test these Infinity’s

The NAD 2100s aren't even half the amp the Adcom GFA-555 is. 250 wpc at 4 ohms "music power" (milliseconds long burst) vs the 555's 200+ watts RMS per channel in to 8 ohms and 300+ wpc RMS in to 4 ohms. The 2100s can't do bridged what the 555 can do un-bridged. Un-bridged the 2100s are rated at 50 wpc at 4 ohms RMS.

I don't think the 2100s would be a good match for the 2.5s. They are likely to clip and damage something if driven at any substantial volume.
 
I don't think the 2100s would be a good match for the 2.5s. They are likely to clip and damage something if driven at any substantial volume.

Totally my concern with the "better" Infinity speakers- you really have to have the right amplification for your needs. More is OK, less, not so much.
But, for the OP, keep your expectations to a minimum, as these are interim speakers and you'll be fine. If they become long term items, and you could do a lot worse, plan on matching up the right amplifier/s.
 
The NAD 2100s aren't even half the amp the Adcom GFA-555 is. 250 wpc at 4 ohms "music power" (milliseconds long burst) vs the 555's 200+ watts RMS per channel in to 8 ohms and 300+ wpc RMS in to 4 ohms. The 2100s can't do bridged what the 555 can do un-bridged. Un-bridged the 2100s are rated at 50 wpc at 4 ohms RMS.

I don't think the 2100s would be a good match for the 2.5s. They are likely to clip and damage something if driven at any substantial volume.

Yep, I figured that out after I got home and really checked the specs. The 250W is their
‘Envelope’ power and not the continuous RMS.

I did find another NAD C272 which starts with 150WPC and goes much higher with bursts.
It’s also not that old, but yeah, $400 can’t get you too far... I’m definitely gonna start with
Something in that range and move on to a biffier amp later , and since so many recommended the Adcom, I guess this is it.
 
Totally my concern with the "better" Infinity speakers- you really have to have the right amplification for your needs. More is OK, less, not so much.
But, for the OP, keep your expectations to a minimum, as these are interim speakers and you'll be fine. If they become long term items, and you could do a lot worse, plan on matching up the right amplifier/s.
Yep, saving up :)
 
I had two new ideas for other options driving the infinitys, with much power and relatively low budget-
The emotiva A-300- a Class A/B amp, 300 wpc @4 ohms , 3 years full warranty, 30 days
Return option, made in the USA and it’s got some pretty good reviews... $399.
https://emotiva.com/products/a-300

The other is a Crown xls1502 , a Class D amp with more then 500wpc at 4 ohms, it’s dead silent, with a proper protection circuit for the speakers. It’s not a ‘home’ hifi, I know but it’s well made and has plenty of oomph.
$399. It has also many good reviews from home users.
https://www.crownaudio.com/en/products/xls-1502
Again- these are short term options, at the same price of these Adcoms 555 which are usually twenty something years old...
 
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I'd take the Emotiva over the Crown (class-D) any day of the week. Yes I'm biased - not a class D fan.

I'd also take the Adcom GFA-555 (first gen) over both of them. /Vastly/ better amp.

The GFA-555 is one of the best amps $400 can buy. Period, end of story.

I now own 2 amps which are without question better than the GFA-555... But they also cost, on average, more than two and three times its average cost, respectively.

If you want to spend $1000 per amp, I have recommendations. Similarly at $1500+ per amp. If you want to spend ~$1000 for a pair? Adcom GFA-555s. All day.
 
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This isn't to brag, but for perspective -- my speakers are highly resolving electrostats. Amp quality makes a huge difference with them. Every source and amplification change I've made has been like night and day in terms of experience. If I needed the money I'd go back to the 555 tomorrow and still be quite happy.
 
'd take the Emotiva over the Crown (class-D) any day of the week. Yes I'm biased - not a class D fan.
Now I'm not judging your bias against class D amps or class D amps themselves, but . . .
Back in the '70's my favorite hi-fi store was Tech Hi-Fi, in this case in New Haven. They were an Infinity dealer and they had on display a rather large member of the Quantum Series of the time- The Quantum Line Source. They had these unusual amps powering them. I didn't know much about them and asked a salesperson. He said something to the effect-" They're special amps , Class D, you won't see many of them, don't concern yourself with them". These Class D amps existed solely to serve the power hungry Infinity's.
I guess what goes around, comes around.
 
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Now I'm not judging your bias against class D amps or class D amps themselves, but . . .
Back in the '70's my favorite hi-fi store was Tech Hi-Fi, in this case in New Haven. They were an Infinity dealer and they had on display a rather large member of the Quantum Series of the time- The Quantum Line Source. They had these unusual amps powering them. I didn't know much about them and asked a salesperson. He said something to the effect-" They're special amps , Class D, you won't see many of them, don't concern yourself with them". These Class D amps existed solely to serve the power hungry Infinity's.
I guess what goes around, comes around.

Who was manufacturing class D amps in the 70s of any quality at all? Please let me know.
 
Who was manufacturing class D amps in the 70s of any quality at all?

So to the best of my knowledge nobody. I had never heard of a Class D amp before then, and was unaware there were "good" class D amps available until recently. This was apparently an amp designed for these speakers; per the the product promotional literature you can see at Bobby Shred's (http://bobbyshred.baberuthband.co.uk/infinity/qls.html) you can see the QLS's "Suggested Amplifier Power Range: 500 Watts per channel RMS".
Now there weren't a lotta amps putting out the kind of power that these speakers required; especially at two ohms.
So, can I back it up, no. Do I think the guy was lying to me, no
I did find this. I don't know how relevant it to my personal experience, but it shows an Infinity Class D amp and the material is dated 1976 (printed at the very bottom.
http://www.davidsaudio.com/Infinity_DSP.pdf

So while appreciate your skepticism, you can hold back on the attitude next time.
 
So I finally had the opportunity to drive and check the RS 2.5.
The speakers were stored for more then 5 years unused in the sellers parents attic.
First impression- the condition is great, the wood is intact, the woofers were
Re foamed 5 years ago and everything was kept under plastic bags.
The foam on the front baffle is falling apart but that’s an easy fix...

We connected the speakers to my 9090db (the seller changed his mind about selling
his Adcom amp...), I connected my phone and I was just amazed with the sound of these speakers! Wow! This is not just a hype. I was surrounded with music.
Then, I put my ear against each driver and I was disappointed (and surprised) to discover that the two lower EMIM drivers don’t work.everything else was just fine.
I did have my multimeter in the car and I checked both drivers which showed 3.2 ohm. Good right?.......Not!
What I didn’t notice in that dark attic is that these mids are connected in parallel ( I also thought that the wires are soldered so I didn’t disconnect before testing ),
And everyone knows that in parallel position, if both are working properly I should not see 3.2ohm but around a half of that... but at that moment I thought that I’ll find out later what’s wrong and as long as these EMIMs shows resistance, so all is good.

I told the seller that I’m taking a chance here because the two don’t output any sound , he already took the price down from 1000$ to 700$ And after all, the pair looked great and sounded just amazing As is, So I decided to take the chance and buy them.
I got home and disconnected the wires from one of the drivers
And for my disappointment it was ‘open’. Same with the other.
So now I need to find two drivers. Or with a little luck fix the current ones.

Anyway-thanks a lot for your fine advice!
 
So I finally had the opportunity to drive and check the RS 2.5.
The speakers were stored for more then 5 years unused in the sellers parents attic.
First impression- the condition is great, the wood is intact, the woofers were
Re foamed 5 years ago and everything was kept under plastic bags.
The foam on the front baffle is falling apart but that’s an easy fix...

We connected the speakers to my 9090db (the seller changed his mind about selling
his Adcom amp...), I connected my phone and I was just amazed with the sound of these speakers! Wow! This is not just a hype. I was surrounded with music.
Then, I put my ear against each driver and I was disappointed (and surprised) to discover that the two lower EMIM drivers don’t work.everything else was just fine.
I did have my multimeter in the car and I checked both drivers which showed 3.2 ohm. Good right?.......Not!
What I didn’t notice in that dark attic is that these mids are connected in parallel ( I also thought that the wires are soldered so I didn’t disconnect before testing ),
And everyone knows that in parallel position, if both are working properly I should not see 3.2ohm but around a half of that... but at that moment I thought that I’ll find out later what’s wrong and as long as these EMIMs shows resistance, so all is good.

I told the seller that I’m taking a chance here because the two don’t output any sound , he already took the price down from 1000$ to 700$ And after all, the pair looked great and sounded just amazing As is, So I decided to take the chance and buy them.
I got home and disconnected the wires from one of the drivers
And for my disappointment it was ‘open’. Same with the other.
So now I need to find two drivers. Or with a little luck fix the current ones.

Anyway-thanks a lot for your fine advice!

Congrats on your purchase, and I'm sure you'll get them going properly again, but as had been discussed, the 9090 won't be up to task running those. Be very careful, do not play them loud at all.
 
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