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Were Renaissance 90s the best Infinity?

timpani said:
I have not heard the Sigmas but I agree in principle with your comments. I have sim'd the crossover response of the Ren 90's and there is quite as 'S' shape through the EMIM - EMIT crossover region including a 2.5dB peak at 2.3kHz. The crossover has been computer designed but most of the values comply with the 5% standards to cut costs. Looking at the crossover schematic of the Sigma's it's easy to see that it's very fine tuned because the values are all 1 or 2% and do not comply with the 5% range.

The good news for Ren 90 owners is that there is some scope via component value mods to make the Rens sound essentially the same as the Sigmas above about 500Hz. I own Ren 90's and I have done some serious mods that have transformed them into giant killers. I'm about to upgrade the caps in the LF crossover and I'm expecting a big improvement in bass - quality and quantity. Having looked at the schematic it's easy to see that SQ will be heavily linked to the performance of 2 NPE electrolytic caps. My own Ren's don't sound as punchy and tight in the bass as they did from new so I'm looking forward to the results.
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I have come to that (late) realisation too; in about 3 months, I will be taking my Rens to a high end audio engineer to get a serious external crossover built & to get my Rens completely re-wired with high end cable. Because my Audio Engineer is seriously good, the results should be stunning. Just replacing that cheap Monster cable with demonstrably better cable alone will make a big difference. Can't wait! Will report back on the results later in the year :D
 
timpani said:
I have not heard the Sigmas but I agree in principle with your comments. I have sim'd the crossover response of the Ren 90's and there is quite as 'S' shape through the EMIM - EMIT crossover region including a 2.5dB peak at 2.3kHz. The crossover has been computer designed but most of the values comply with the 5% standards to cut costs. Looking at the crossover schematic of the Sigma's it's easy to see that it's very fine tuned because the values are all 1 or 2% and do not comply with the 5% range.

The good news for Ren 90 owners is that there is some scope via component value mods to make the Rens sound essentially the same as the Sigmas above about 500Hz. I own Ren 90's and I have done some serious mods that have transformed them into giant killers. I'm about to upgrade the caps in the LF crossover and I'm expecting a big improvement in bass - quality and quantity. Having looked at the schematic it's easy to see that SQ will be heavily linked to the performance of 2 NPE electrolytic caps. My own Ren's don't sound as punchy and tight in the bass as they did from new so I'm looking forward to the results.
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Welcome to AK and the Infinity forum timpani!
I look forward to hearing how this works out and the results you get with the updated crossover.
 
Caps for LF crossover - Ren 90

Hi Melbguy,
I've been struggling to find options. It seems that there are not many manufacturers of large value NPE caps. I have just bought 8 x 220uF 100V NP's from Electus - the wholesale arm of Jaycar. They are M.D.L branded - made in China but are 'supposed' to be high quality and low distortion (low C modulation). I doubt I will have time to install them before the weekend but I'll report back via this thread late Sunday. BTW, the 8 x 220uF will replace 2 x 880uF (1 in each speaker). I will therefore be using 4 x 220uF to replace each 880uF. This is obviously a bit bulkier but the 4x in parallel will result in a lower series resistance and therefore less Q loss. These caps form the LC BP for the 2 ohm winding which represents the bottom octave so it will be immediately obvious if the old caps have aged and gone out of spec. ESR differences will be very magnified with such a low load impedance so if I hear more low bass it can only mean there's an improvement, and the more low bass - the more the improvement.

I hope I can report a positive outcome because the implications will be significant for all Ren 90 owners. BTW there are 2 other caps (1 per speaker) that affect the upper bass that I will also replace - pending the outcome of this experiment.
 
timpani said:
Hi Melbguy,
I've been struggling to find options. It seems that there are not many manufacturers of large value NPE caps. I have just bought 8 x 220uF 100V NP's from Electus - the wholesale arm of Jaycar. They are M.D.L branded - made in China but are 'supposed' to be high quality and low distortion (low C modulation). I doubt I will have time to install them before the weekend but I'll report back via this thread late Sunday. BTW, the 8 x 220uF will replace 2 x 880uF (1 in each speaker). I will therefore be using 4 x 220uF to replace each 880uF. This is obviously a bit bulkier but the 4x in parallel will result in a lower series resistance and therefore less Q loss. These caps form the LC BP for the 2 ohm winding which represents the bottom octave so it will be immediately obvious if the old caps have aged and gone out of spec. ESR differences will be very magnified with such a low load impedance so if I hear more low bass it can only mean there's an improvement, and the more low bass - the more the improvement.

I hope I can report a positive outcome because the implications will be significant for all Ren 90 owners. BTW there are 2 other caps (1 per speaker) that affect the upper bass that I will also replace - pending the outcome of this experiment.
Click to expand...

Hi TImpani, your x-over mod sounds impressive! I am not technically skilled like yourself (i'll leave that to my Audio Engineer) however I hope to eventually report back with an interesting thread with photos of my system & x-over mod later this year. Cheers :thmbsp:
 
Melbguy,
Since your Ren's have only had light use the caps are probably still pretty good. In fact they may benefit from a bit more 'running in' again if they've not been used for some time. As much as you're looking forward to having them modded for maximum performance I would be inclined to take plenty of time to first get get to know them so that you become very aware of their existing strenghts and weaknesses - with the rest of your system. When you are happy that you've fine tuned them as far as you can go in your system - via cable changes, tweaks, room positioning etc, then is the time to think about mods and upgrades to the internal cables and passive components. I have indicated in a previous post that the Ren's present plenty of room for upgrades - and they indeed do, but keep in mind that you are putting a great deal of faith in your AE friend to deliver a full bag of upgrades that you will be fully happy with. I see that as a potential risk because unlike myself and other active modders you will not be able to simply undo a mod if you decide it's not a step forward or if it's perhaps one step forward but two steps backwards - if you get my drift. As an example, upgrading capacitors may seem like a simple task - you take one out and put a better and usually more expensive one in. However there are instances where a technically worse performing cap actually works better. The designer might be using the specific ESR to produce a particular Q factor that just happens to provide the flattest response. So the waters can be muddier than you might think. Yes you can find a better souunding cap but then you need to use just the right amount of series resistance to restore the designed Q. I say all of this not to put you off having the mods done but just to make you aware that it's not an easy task for your AE friend - and much more so if they are not the same speakers he lives with day in and day out. On the other hand if your relationship with this guy is such that he will also provide the required post mod fine tuning then you have much less to worry about.
Good luck with the Ren's and the mods and the nirvana that awaits. Please don't hesitate to ask me - anytime now or down the track if you need any tech info on the Rens or my mods.
 
I would think that someone around here knows someone who was around when Infinity designed and produced these speakers. It could be very beneficial to get their insight and opinion on how this speaker can be further improved, without losing any of its already great qualities.

I know that I would like to be able to take my Ren 90's to another level of performance.
 
Every speaker's c/o can be fine tuned to a specific room and location in the room, especially the bass section. Installing a couple of 2-3 db boost-cut DIL 3 way switches (a' la Sigma) can provide great flexibility and can return the sound to factory default.. More drastic c/o changes will change the character of the sound, (not a good thing) unless you don't care about the value and authenticity of the speaker. Infinity have always voiced their speakers in big rooms, 5-6 ft away from walls. In this case no mod is necessary, and you' ll be better off installing bass traps and room treatments. If you still want to do it, mod one speaker first or better yet, have an original pair next to yours for comparison.
In the end mods are fun. Keep us posted. :thmbsp:
 
IRS Sigma

I ran a sim on the Sigma's EMIT - EMIM crossover region and it looks totally different to the Ren's. The Ren's exhibit peaks at 2.3 and 4.0 kHz while the sigma's exhibit a broad 2dB dip at 3kHz. This could be a correction for the rising on axis response above 2 kHz from the EMIM - due to beaming. If this is the case then the Sigma's should sound slightly more neutral when listening on axis and should sound a bit laid back when off axis.

In general the Ren's should sound more forward in the upper mids while the Sigma's could sound quite laid back depending on toe-in.

I would be interested to hear comments from Sigma + Rern owners to see if these measurements correlate with the subjective differences.
T
 
timpani said:
Melbguy,
Since your Ren's have only had light use the caps are probably still pretty good. In fact they may benefit from a bit more 'running in' again if they've not been used for some time. As much as you're looking forward to having them modded for maximum performance I would be inclined to take plenty of time to first get get to know them so that you become very aware of their existing strenghts and weaknesses - with the rest of your system. When you are happy that you've fine tuned them as far as you can go in your system - via cable changes, tweaks, room positioning etc, then is the time to think about mods and upgrades to the internal cables and passive components. I have indicated in a previous post that the Ren's present plenty of room for upgrades - and they indeed do, but keep in mind that you are putting a great deal of faith in your AE friend to deliver a full bag of upgrades that you will be fully happy with. I see that as a potential risk because unlike myself and other active modders you will not be able to simply undo a mod if you decide it's not a step forward or if it's perhaps one step forward but two steps backwards - if you get my drift. As an example, upgrading capacitors may seem like a simple task - you take one out and put a better and usually more expensive one in. However there are instances where a technically worse performing cap actually works better. The designer might be using the specific ESR to produce a particular Q factor that just happens to provide the flattest response. So the waters can be muddier than you might think. Yes you can find a better souunding cap but then you need to use just the right amount of series resistance to restore the designed Q. I say all of this not to put you off having the mods done but just to make you aware that it's not an easy task for your AE friend - and much more so if they are not the same speakers he lives with day in and day out. On the other hand if your relationship with this guy is such that he will also provide the required post mod fine tuning then you have much less to worry about.
Good luck with the Ren's and the mods and the nirvana that awaits. Please don't hesitate to ask me - anytime now or down the track if you need any tech info on the Rens or my mods.
Click to expand...

Hi Timpani, I agree kind of that caps would be in (comparatively) good condition, but all caps of that vintage will degrade over time. And let's be honest, that crossover is not a blue ribbon crossover. It's ok, but a well-build external crossover should raise the speaker quantitatively to a higher level.

I agree completely with your comments about the most expensive caps not always being the best in regard to values and, more particularly - sound. Don't worry, my AE is basically the best Audio Engineer in Australia and much of this part of the world. He is seriously good, trust me. Also, we will be voicing the new crossover using a demo Classe pa identical to the one I will be buying next year matched with a tube pre-amp for accuracy :D. I also agree with Bastek, sometimes not deviating too far from purity is a good thing (aka IRS Sigma boost-cut switches). Whatever I do; my brief to the Audio Engineer whom I regard as a genius will simply be: "Do your best work yet, and build me the best crossover possible to make these speakers sing". I will report later.....

Best regards,
Melbguy1
 
Melbguy1:

Are you planning to let us know what the changes are as well the how they sound afterwards? A BOM would be cool so that others can try the upgrade as well :)
 
Inspiribomb said:
Melbguy1:

Are you planning to let us know what the changes are as well the how they sound afterwards? A BOM would be cool so that others can try the upgrade as well :)
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Hi Aaron, yes early days yet. I am taking delivery of the Rens in about a week (all things going well), although i'm currently ebaying a lot of ic's & saving for higher end cables, so I may not actually get the opportunity to do some listening for about 6 weeks :( Once i've got that sorted out, I will have the Rens connected to my Classe integrated for a further 6 weeks or so before they go in for their rebuild. That should be enough time for my new cables (and Classe) to burn in nicely and give me a good frame of reference to compare the changes when I get them back.

Later in the year, I will be posting a thread which includes photos of the Rens arriving in their C&F crates, being unpacked, placed in my system & of course being opened up for their rebuild, photos of the crossovers being built together with before/after listening notes & a x-over schematic and parts list. After exhaustive study about cables, I decided on Acoustic Revive & have AR Bi-wire cables on their way from Japan now. I will also be using AR single core jumpers & internal wiring in the 90's to maintain uniform passage of the signal from amp to driver.

Cheers :thmbsp:
 
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Thanks Melbguy1! I really look forward to seeing that thread and to what extent their performance is either improved or diminished.
 
Melbguy1 said:
Later in the year, I will be posting a thread which includes photos of the Rens arriving in their C&F crates, being unpacked, placed in my system & of course being opened up for their rebuild, photos of the crossovers being built together with before/after listening notes & a x-over schematic and parts list. After exhaustive study about cables, I decided on Acoustic Revive & have AR Bi-wire cables on their way from Japan now. I will also be using AR single core jumpers & internal wiring in the 90's to maintain uniform passage of the signal from amp to driver.

Cheers :thmbsp:
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Melbguy, that will be excellent. I look forward to seeing the revised schematic and the component list.

Some info in the meantime: -

I sim'd the entire Ren 90 crossover today and after adding time alignment corrections the response is essentially within a 4dB envelope from 27Hz to > 10kHz. With a few minor tweaks you can easily acheive +/- 1dB. One aspect of the design that's interesting is the crossover from mid bass to EMIM. The MB crossover slope is 18dB / octave but the EMIM slope is 24dB / octave. At a glance this looks wrong but in fact the design takes into account the roll off of the EMIM below 600Hz. The EMIM HP slope is therefore effectively 30dB / octave.

There are 2 key NP Electrolytic caps.
C4 = 33uF - EMIM
C8 = 140uF - MB

I recommend changing C4 to a PolyP film cap along with a small value change to 30uF and + add 0.22R in series.
C8 should be changed to a very hQ 100uF NPE in parallel with 22UF pOLYp - OR 120uF polyP which will cost a small fortune. All other Solen caps should be changed to a HQ PolyP film cap of the same value. Make sure all caps are 2% or better. The iron core inductors in the MB crossover should all be changed out to air coils - again 2%. These changes will significantly reduce distortion and the mids will be more pure and far more detailed.

I have already changed C4 (as above) in my Rens and there was an immediate improvement. Any non linearity in this cap will result in the so called non linear distortions. Ditto C8.

Recommended changes to EMIM cap values:

C1 = 3.9uF. change to 3.3uF
C2 = 5.6uF. Change to 6.6uF

This gives a flatter response and should be done in conjuction with the change to C4. I am using Mundorf SIO with a 35V bias - as per IRS Epsilon. The treble is far more grain free and very sweet with these caps.

BTW, I didn't have quite enough time to change the Caps in the woofer crossover but I have a week holiday starting next Friday so I'll devote some time to changing them plus upgrading C8. I spent today working on a new CLASS A preamp based on the LM4562. My reference pre is a Krell KSP-7B so it will be interesting to compare when finished.
 
Hi Timpani,

Thanks for the x-over recommendations! Do the above recommendations cover the low frequency crossover section? If not, please post your recommendations after you've worked out that section also. Your extensive research and notes will certainly provide valuable key points to consider in designing the best possible crossover mod for my Rens :thmbsp:
 
Melbguy,

Re LF crossover, Those inductors are very large values so air core is really out of the question. However, it should be possible to find higher quality substitutes and I'll set about doing that this week. There's less room for tweaking the crossover values in the woofer - due to the crossover design and required Q. However, if we can source lower loss inductors and capacitors there will be a reasonable increase in efficiency. When I have the cabinets open to upgrade the woofer caps I will make a point of measuring the inductor resistance - which will allow me to calculate the efficiency improvements through use of better components.

The Dual coil is a novel approach but you don't get something for nothing. The implementation is quite costly if you want a killer result - due to the quality of caps and inductors required, and then you need a very high current amplifier. Actually the current demand will get even bigger with low loss components.
But yes, I'm also looking forward to hearing what the WW design can do when it's implemented to a near ideal performance.
 
Melbguy,

I tried manipulating values in LTS and found that it's possible to improve the low frequency response by decreasing the Q of the 2 ohm BP. It might actually be possibe to improve efficiency too because the use of a larger cap and a smaller inductor will reduce DCR / ESR. Using the steel laminate inductors (Madisound) as a reference it was possible to improve efficiency by 1.5dB by lowering the Q. This is possible because the lower value inductor has a lower DCR. I've checked the resulting impedance and there's a slight change but it's still just above 2.5 ohms at 40Hz. The good news is that the revised values also fix the 2dB dip at 60Hz and reduce the peak at 90Hz. The bass should sound more even and will have a bit more punch, and the -3dB point is a few Hz lower too.

Subset of all changes to the woofer X/O

L11 > change from 18mH to 12mH Steel laminate 15WG
C12 > Change from 840uF to 1600uF (use at least 2 caps in parallel)
L9 > change from 12.7mH to 11mH Steel laminate 15WG
C9 > change from 250uF to 300uF
C11 > change from 100uF to 110uF (add 10uf polyp in parallel with existing)


I will mod all as above within the next 2 weeks and will report back. Nothing ventured nothing gained. :music:
 
Hi Timpani, I agree entirely with your conclusions regarding the Watkins woofer - a terrific design which eats current like m & m's. Thanks for sharing the progress of your x-over mods to your Rens as your findings can only assist other owners such as myself in future :)
 
Answering the post title question. Sorry, the Servo-Static (their very first product made in a garage) was the top of the line and best sounding Infinity made. But, sadly, not the most reliable. Probably the least reliable.

I lived with a set for at least 15 years as my system.
 
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