Infinity Renaissance 90 questions


Hi fellow AG'ers, I have just pulled the trigger & purchased a pair of Ren 90's in black ash & had some newbie questions for more experienced members. Firstly as they are still shipping from the US, I'd love to know what finish (Black ash or blonde oak) you prefer? In my case, a micky mouse pair came up for sale at the right price in Black ash, so I grabbed them..

Also, I will be initially running my Rens with a Classe Cap-2100 integrated amp which has been bench tested at 235watts/4 ohms. I know most punters advocate giving them 400 watts per channel, so what do you think? (although the Classe has a truckload of current to compensate). I should mention I plan on upgrading to a Ca-2200 pa & AR Reference 3 in a few years, but for now, the Cap will doing regular duties.

Finally, I would be interested to hear from any members who have re-wired their Rens & had a high-end external crossover built & what results you got? I am planning a very high end x-over mod & re-wire of my Rens with Acoustic Zen wire next year and would appreciate any suggestions.

Cheers!
melbguy1
Melbguy, If you're completely happy with the tonal balance then it's good advice to leave them alone.

FWIW I'm using a 10 year old Meridian 557 to drive the Woofers, Mid Bass's and EMIM's and I designed and built my own amp for the tweeters because I couldn't find anything commercial with the smoothness and refinement I was after. The EMITS can sound a bit metalic with some SS amps and my own design - using a mosfet output stage with bipolar drives in CFP configuration results in a very sweet fluid treble while the gutsy Meridan gives me the dynamics and control from the mids and down to the sub bass.

I find the Ren 90's a tour de force when it comes to 3d imaging. I'm yet to hear another large speaker that can present a 3D image the way these can.
That's an interesting set up on your Rens Timpani. Speaking the obvious, but smooth watts are very important for the Emits! I can certainly understand the popularity of running a ss amp on the Watkins & tube power for the highs, but I feel that running separate amps for lows/highs creates phase issues and (personally) I feel using tube amps introduces microphonics which muddy the sound of highly revealing speakers like Rens.

What interested me about your hand-made tweeter amp was how similar in concept it sounds to Classe amps which employ Jfets in the input stage, Mosfets in the driver stage & Bipolars in the output stages. It's certainly rewarding and exciting to invest in that level of amp, but more fun if you can design and build your own!

Incidentally, I have a friend who is an Infinity sceptic. He actually sold a smattering of Infinitys back in the 90's (eg: IRS Epsilon), but he never heard Renaissance 90s. His common line is that Infinitys "lack coherancy". His favorite speakers are ML's, and in fact he tried to persuade me to buy a pair of CLS 2z's off him recently. I felt they had inherent weaknesses in that they are absolutely reliant on an add on subwoofer & good room acoustics. My response to him was "just wait till you hear the Rens!"
Re the phase issues, yes you are correct and my adapted tweeter crossover uses some conjugate matching to minimise the sharp phase transitions. Infinity's are not everyone's choice and your friend may have a valid point, however, the issue of coherence can be minimised with careful attention to speaker placement and the right choice of a listening room. Any 4 way speaker will need more distance to generate a coherent wave and the ren's are no exception. One big advantage of planar drivers is that the impedance is flat and resistive not only within but also well outside the operating range, so passive crossover design is far easier to get right and can be achieved without RLC networks that rob efficiency and introduce other side effects. Planar driver impedance also remains constant with power which is a source of non linearity with cones or domes. Every design has strenghts and weaknesses and the 90's are not perfect but they really don't do anything very wrong and what they do very right is difficult to live without once you have lived with them for a while. BTW from my brief experiences with Classe amps I think they are an excellent choice for the Ren's but I'm sure you will hear improved dynamics when you upgrade to the CA-2200. I would like to hear that setup. BTW I live in Sydney and bought my Ren 90'S new back in 1995 from Audio Excellence. The RRP at the time was $7999 but they gave me a nice discount. I have owned many other speakers including B&W 801 but these are my fav.
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I own a pair in blonde oak. They are beautiful and sound incredible. Female voices on them are so good that the realism is down right scary.
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Timpany, thanks for sharing your technical experience with the Ren 90's. As most fans of these speakers would know, there are basically no reputable critical reviews to be found online, and therefore no lab reports etc..you're relying on Infinity's semi-technical white paper; so I and i'm sure many other Ren 90 owners would appreciate your comments.

I was interested in your comment that planar driver impedance remains constant with varying input & your point that this is otherwise a source of non-linearity with cones as one of the technical achievements of the Infinity/Watkins woofer was how the secondary motor was only allowed to operate in the low bass region where the impedance was much to high anyway, thus flattening the impedance peak at resonance and lowering it to a correct level (which provided a less reactive load with less phase shift, thus largely eliminating non-linearity in a cone design).

Also picking up on your comment about the difficulty of achieving coherancy in a 4 way speaker design, Infinity appear to have gone to great lengths to design a unique cabinet and grille which virtually eliminated resonance and diffraction and provided unimpeded and ideal dispersion of the musical signal. If Infinity didn't achieve quite the level of coherency as ML's CLS2, then in a single, conveniently placeable tower, they got bloody close!

Yeah, I was telling Mum the Rens sold for $8000 here way back when & I should land my pair for about $4100 with shipping/fees included, so still a good deal.

Melbguy1

ps: I'll keep a note of your your request to hear the Rens once my system is finally complete. By the end of next year, I plan to add to my existing JVC/Vimak front end with a Reference 3 pre-amp, Ca-2200, AR/Jorma cables, Running Springs filter, SRA platforms & new maple cabinet.. "Phew!"