Infinity Renaissance 90 questions

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!"

Melbguy + others

IMO the only real shortcoming of the emit tweeter is the narrowing dispersion at very high frequencies. This results in a rolloff of high frequencies above 10KHz at > 25 degrees off axis and a rising response - on axis. For this reason the amount of 'toe in' becomes very critical in achieving the right tonal balance which makes then Ren's more of a 'one person' speaker because the sweet spot is very narrow. I have experimented (in the past) with ribbon super tweeters (sitting on top of the cabinets) to supplement the dispersion above 10Khz but I found that it was best to cross over (via a passive network) just above 10KHz, but the additional crossover introduces time alignment complications which can take plenty of listening time to fully optimise. However I was able to acheive excellent results using Raven R1's as super tweeters with a first order crossover at 10KHz. This made the horizontal dispersion really wide and gave the treble more 'air' creating an even bigger soundstage. Unfortunately the trade off was poorer vertical beamwidth (due to the distance between the EMIT and the Ravens) and this made listener height more critical. However I did persist with this setup for some time because it worked better in my room. I'm now using Raal ribbon tweeters which sit on top of the cabinets and the EMITs are no longer connected. This avoids the interactions between tweeters but the larger distance between the EMIM and the Raals does reduce the vertical sweet spot. I will probably (ultimately) go back to using the EMITs with the Raals purely as super tweeters because the EMITs IMO are better than all of the pure ribbon tweeters I've tested in the low range (2 - 6 KHz). The Ravens in particular are very poor performers below 6KHz where they sound very thin and dynamically very lacking. They are a very over rated tweeter IMO but they do work well as super tweeters due to the 50KHz BW and performance above 10KHz is pretty good.

FWIW I'm about to embark on an upgrade of the caps in the Watkins woofer crossover. The bass is sounding a little bit spongy these days which makes me think that the caps are lossy and need replacing. I will provide feedback to this thread on the outcome of that upgrade in the hopefully not too distant future. I do have the schematic but getting the correct value caps from a reliable manufacturer might be a challenge.

Here is a link to the Ren 90 crossover schematic. I would advise downloading this while it's available. Note there is an error. The 5 ohm resistor in series with the EMIT should read 0.5R.
http://www.kalman.org/RENAISSANCE%2090%20x-over.pdf

Timpani

Thanks Timpani, am not contemplating any refurb of my crossover as mentioned at this stage, but your comments are interesting. Also, which version of the Ren 90 crossover is that, as there were obviously several revisions throughout the production run for the Rens?

Cheers

The xo changes did not seem to find their way into an updated schematic but there must have been errata's sent out to distributors. The only schematics I have been able to find have all had the same values as those in my early gen 90's. The changes I am aware of are in the EMIM LPF (2nd pole) and there were also some updated values in the woofer XO to provide a bit more punch and speed in the bass - at the expense of a little extension. None of these changes make any radical difference but the changes to the EMIM do make the response slightly flatter through the crossover region and address a 2-3dB spike at 2.3kHz. Bear in mind that the values chosen in the EMIM / EMIT crossover are mostly all 5% standard values - which are easy to obtain and result in a lower production cost so there is actually some scope for fine tuning. If you look at the crossover schematics for the IRS Sigma EMIT / EMIM XO you will not find any standard value caps or inductors - hence the higher price tag. Fortunately though the solen caps in the EMIT XO are all very HQ and ditto the EMIM with the exception of C4. This cap is somewhat critical because any capacitance modulation here will result in some audible distortion, which is why I changed it to a BG. The Sigma's address this by using a polyprop cap in parallel with a HQ electro. This is a 50% improvement but I'm sure the Epsilon uses pp throughout.
In summary, the Ren 90's are using the exact same EMIT + EMIM drivers as used in the Sigma's and nearly the same quality of crossover components - save for one cap. The main difference seems to be that the Sigma's do have fine tuned component values for a slightly more linear response - but remember that subsequent revisions of the Ren XO have largely addressed these so if you are not aware of any colourations then any modding is probably not worthwhile. FWIW I have never heard the Sigma's but it's unlikely that they would offer any significant improvements over the Ren's.

i have owned the sigma's and thought that the woofer did not make a smooth transaction into the mid bass driver, i always felt that the upper bass was lacking thus the reason i sold them, from the midrange up i thought that the sigmas sounded slightly better than the ren 90's probably because they used higher quality caps in them, i now have a pair of ren 90's and i actually like the sound of them better than the sigmas, i also have a pair of kappa 9's that i replaced all the old solen caps in the crossovers tweeter section with new solen caps and after the break in period, well let me say that the new solens sounded like crap and they are the same ones used in the ren 90, i called sonicraft and asked them which caps do they think would sound the best in my kappa 9's and they recommended the wonder dynamicaps over my preference the mondorf silver oils, the fellow i spoke with said that he would sell me either one but that i would be waisting my money if i went with the mondorfs, that the dynamicaps would match the kappa 9's much better, so i bought and installed the dynamicaps in all the crossovers tweeter sections in my kappa 9's, omg what a difference in the sound you hear everything, when i used to compare the kappa 9's to my ren 90's i always thought that the rens from about 5k to 10k sounded much better more dynamics than the kappa 9's, but not anymore, i used to like to listen to my rens but now when i compare them after having done the mod to the kappa 9's the rens sound like you have cotton balls in your ears and i just don't like to listen to them anymore, i wonder if you replaced the solen caps in the tweeters crossover section in the rens with the wonder dynamicaps how much better they will sound, has anyone tried replacing the caps in the rens crossovers tweeter section ? if so what where the results?.
greg