Anybody listen to Graz'd EMIM's?

[Graz]

In answer to questions raised;-

Embossing - yes!

Flying leads. These were decided on for 2 reasons, firstly universal compatibility, secondly and more importantly to avoid interference with the soldered path on the ribbon. The leads are stripped back further than required for a crimp connector and tinned with WBT solder, the stripping and tinning giving enough room to place a heat-sink clamp on them if soldering them. This way you are not overly warming the circuit whilst connecting. My recommendation is to obtain tinned copper crimp-pipe connectors, and bite down on the ends to make a joint. I can supply these if they are hard to get in your area.

Terminals - IMPORTANT. I have had one person feed back that the terminals shorted out the circuit across the metal plate on the back side of the EMIM "clam" that holds the back magnets. Things are tight here, so this is possible. In his case it was an easy fix. This person had 2 drivers for one speaker, 2 for another - it affected BOTH of one speaker type - not the other. Covering the plate edge with kapton tape (I can supply) or even white masking tape provides insulation here, a fix. As the original EMIM's will have tolerances on these metal parts that are not in line with modern laser production and this must be considered. Test the flying leads for a circuit after assembly - 2.95-3.00 ohms is the required range, an odd reading under an ohm can be considered a direct short through the steel. Alternatively this could be an issue of the tab being just a tad high. I solder these all by hand and have flattened these from their supplied 45 degrees to the minimum they could be. On my tests here with the EMIM shell I have they have passed all tests. On a rogue one they may require a bit more careful flattening. If so - pinch BOTH sides of the joint with the tab to support the solder joint to the ribbon on the ribbon side. If possible - this is to be avoided. NEVER twist the terminals around in the hole - it WILL break the joint. They are designed not to corrode and employ different methods to join the front and back circuits than what was originally used. The original terminals were actually galv steel! Easily magnetised, especially where they were...

White wire. I had to buy a few of reels of this wire minimum to achieve the required quality at a price that was in the ballpark of reasonable! Cable is one of the highest mark-up items in the audio chain, and people are scaling back on supply. White will be the colour, apologies to the colour prejudiced


Run in = 70-80 hours to be at their best, please - no burn in cd's!!!


Take care - Graz

 

[Maxamillion]

When I installed the production diaphragms, I cut the flying lead to 3/4" protruding from the back of the shell, then stripped 1/2" of the insulation off, so only 1/4" of the white insulation was showing. I then clamped the lead to the wire from the crossover with a hemostat (on the EMIM shell side of the wire) to hold them together and act as a heat sink to keep the wire from carrying the heat back to the diaphragm, and soldered the two wires together. Just use a hot soldering iron, a heat sink such as a hemostat, and don't leave it too long on the joint, and there shouldn't be problems.

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[Albikes]

My new ribbon diaphragms arrived this weekend. They are quite beautiful and show an attention to detail that the originals never could. It is a little sad that strips of Scotch Tape were employed to give strength and damping on the stock component.

I'm installing the Graz ribbon on my first set of EMIMs that were the standard NdFe magnets for the IRS Delta/Gamma/Beta's. Unfortunately, these were from some abused Delta/Gammas that showed significant corrosion with Ni plating curled up and magnets that, while very powerful, flake away and turm to powder when you rub your finger over the metal. I did my best to gently remove the flaking Ni coating, then used the Bill trick of dropping Crazy Glue on the porous magnets to help hold them in place and together. I think it has worked. Next I will smooth the magnet surface that faces the ribbon, then apply conformal coating as Max recommends. Also, I will try to find a replacement nylon cloth material to put in place of the original so as to stop light transmission through the driver.

So, still a little work to do before I can give a sound impression report. But I will!

I can tell you that the set of pristine Gammas that I drove to pick up in Denver do play wonderfully and amaze me with life like bass response. The servo controller does work as advertised. Also, on this set, compared to the Lake County abused set, there is no Ni plating flaking away, the conductant shows no rippling along the stock diaphragm. They are in great shape and sound stunning. To do a direct drop in Graz ribbon replacement comparison, maybe I should use these drivers as a test?

Albikes

 

[Maxamillion]

I can tell you that the set of pristine Gammas that I drove to pick up in Denver do play wonderfully and amaze me with life like bass response. The servo controller does work as advertised. Also, on this set, compared to the Lake County abused set, there is no Ni plating flaking away, the conductant shows no rippling along the stock diaphragm. They are in great shape and sound stunning. To do a direct drop in Graz ribbon replacement comparison, maybe I should use these drivers as a test?

Albikes

Using the EMIMS with the perfect magnets and comparing to the perfect stock EMIM diaphragms would be the ultimate test for the Graz diaphragms. You would thus eliminate the effects of bad magnets and rippled stock diaphragms from consideration.

 

[Maxamillion]

By the way, I have now installed Graz's production version EMIM diaphragms in my RSIIbs.

Prior to this I had been using a set of prototypes that were a bit more loosely tensioned (among other things) and I had found that using 0.5mm thick Lexan spacers front and back of the diaphragms gave me the best combination of sound clarity and excursion; without them the prototype diaphragms would hit the magnets on very loud passages. These are NOT needed with the production units. Graz made a few improvements which limit the overexcursion of the prototypes (based on the feedback on the prototype units), and I have found that running them without the front spacer gives me better sound without the diaphragms hitting the magnets. I left the back spacer in because that gives me the same total thickness (3.0mm) that my stock diaphragms used - I think the diaphragm thickness was increased from 2.5mm to 3.0mm in going from the SmCo magnets to the NDFeB magnets. I'm not sure that I need the back one either but I left it in just to maintain the same thickness as my stock units had.

 

[Albikes]

OK, talked myself into it. With your help, thanks Max. I've just removed the EMIMs from the pristine set of Gammas. I've cleaned the solder off the stock leads so it slides through the slots on the rear clamshell. The magnets look as new, I think I will do nothing to them now.

When wiring up the Graz ribbon, is the rear right(gold/yellow kapton colored) lead the positive(+) as on the original diaphragm?

Your help is appreciated.

Thanks,

albikes

 

[Graz]

Hello Al

Side for side, the connections are as per the original!

Take care - Graz

 

[Albikes]

Thanks Graz! So I've put the ribbons in, oh so pretty, and used some damping(like Dynamat) 1/2" strips on each side of the clams, and black electrical tape over the exposed steel magnet baseplates to ensure no grounding of the leads nor rivets. I'll have sound in a little while.

To minimize stress on the power lead rivets I have the rear right side + lead comming throught the stock - slot, and vice versa. Leaves about 2" of wire at the back of the driver.

Albikes

 

[Albikes]

Subtle yet profound is what comes to mind after listening to the Graz'd ribbon EMIMs on my IRS Gammas.

I've been on a jazz music kick for the last few weeks, usually taking a listen to Dave Brubeck and Miles Davis during each listening session. Tonight, after the ribbon install, I did the same. There is a clarity, substain, timbre, and stage that is all more noticable now. That's with just the Graz ribbons in place. Everything else is as before, and completely stock, albiet in excellent condition.

I can only imagine how nice a crossover rebuild would be with the rebuit midrange drivers. Or, imagine this, with new LEMIM and EMIT ribbons too. Oooooh, aaaaah. Can you make those Graz?

Albikes

 

[Maxamillion]

They get better with some break-in. I have noticed that more of the microdetails get through as the ribbons loosen up a bit - 80 hours or so to reach their peak, according to Graz.

Congratulations on joining the club!

 

[rs1b]

They get better with some break-in. I have noticed that more of the microdetails get through as the ribbons loosen up a bit - 80 hours or so to reach their peak, according to Graz.

Congratulations on joining the club!

Have you noticed an efficiency difference ? I find on my 1B's and the 2B's that I have turned them back at least 10%.( I only did the uppers mids) Perhaps the fact they are lighter and have slightly lower impedance ( 2.9 vs 3.2) might also make a difference. Also I hear more upper frequency response and suspect that may be the case again that could be due to a lighter diaphragm. Any thoughts on that.

 

[Maxamillion]

The frequency response with the production Graz diaphragms is pretty flat for me - here is the in-room response plot - I have purposely set up the slight downward slope from 20Hz to 20kHz because that sounds best to me. It is especially flat in the High EMIM region (800-4000 Hz).

I am using my upgraded outboard x-overs, so a comparison to your set may not be 100% appropriate, but my x-overs do match the stock values.



.

 

[rs1b]

The frequency response with the production Graz diaphragms is pretty flat for me - here is the plot below - I have purposely set up the slight downward slope from 20Hz to 20kHz because that sounds best to me. It is especially flat in the High EMIM region (800-4000 Hz).

I am using my upgraded outboard x-overs, so a comparison to your set may not be 100% appropriate, but my x-overs do match the stock values.

I take it that this is the range of the entire speakers system. Did you do a direct AB comparison on the Graz Emim vs your stock Emim only with crossovers. I am curious about the upper range difference. I also noticed that the RS2B's used ( at least on mine) avery high quality original membrane. It was tranparent and very tight unlike my RS1B's where they used good ole tape to keep it from buzzing and was quite floppy. I here a greater improvment on the 1B's that the 2's.

 

[Maxamillion]

My RSIIbs had the same old taped-over diaphragms as your 1bs. Unless you've had the speakers since they were made, it's hard to know what previous owners did as far as swapping EMIMs. My IIbs had 4 Neo EMIMs and 2 SmCo EMIMs when I got them! Now they are all Neo.

When I first put the Graz prototype diaphragms in, I did only the right speaker, and kept the left with the stock diaphragms. The difference was immediately obvious in terms of clarity, transparency, and transient response. I didn't have my TrueRTA software at that point, but I did plot the stock vs Graz using test tones and a RS SPL meter - the Graz units extended a little lower in the mid-bass region and were flatter at the upper end. I also did several plots of the units from varying distances and at different settings of the adjustment pots. All those graphs are in the closed thread in this forum ("Update on New EMIT/EMIM Diaphragms" was the title, I believe).

Are the new units a little more efficient? Maybe, but well within the range of adjustment provided by Infinity. Remember that the specs on the stock diaphragms were 2.5 to 3.5 ohms on DC resistance, so there could be noticeable differences among the EMIMs even when brand new! The Graz units have 10X tighter specs, and will thus be much more consistent - if you compare them to a 2.5 ohm unit they may sound less efficient, and compared to a 3.5 ohm unit they may be more efficient. That variation in the stock diaphragms is why Bill Legall of Millersound matches them side-to-side when he rebuilds these speakers; there is no need to do that with the Graz diaphragms since they are much more consistent. All the ones I have measure between 2.9 and 3.0 ohms. Mixing the Graz units with the stock units will likely produce different results depending on the actual measurements of your stock diaphragms - the further away from 2.9 ohms they are, the more noticable the difference will probably be.


.

 

[Maxamillion]

Have you noticed an efficiency difference ? I find on my 1B's and the 2B's that I have turned them back at least 10%.( I only did the uppers mids) Perhaps the fact they are lighter and have slightly lower impedance ( 2.9 vs 3.2) might also make a difference. Also I hear more upper frequency response and suspect that may be the case again that could be due to a lighter diaphragm. Any thoughts on that.

By the way, did you notice that the difference between 2.9 and 3.2 is 10%, which is how much you said you needed to adjust the upper mid pot? All that pot does is increase or decrease the impedance of the circuit - looks like you just adjusted the circuit impedance to match the stock units.


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[Albikes]

My stock EMIM diaphragms measured 3.2 and 3.4 Ohms. I did notice the Graz ribbons play a little louder when I first put them in; they measured 2.97 Ohm and it's nicely written on them by Graz on the polycarbonate ribbon support structure. I turned the EMIM adjustment down, about one hours hand worth counter clockwise on a 12 hour clock face. About ten percent, as we see is the norm now. They blend in perfectly.

80hrs break in?! I'm only two hours on my way. Good excuse to listen more and every day

Albikes

 

[siramazing]

second pair in place

I installed my second pair of Graz' Emims a couple of days ago. In an e-mail to me, Graz recommended I place them at ear level next to the first pair I put in, which in my 1-B's were in the 3rd. slot down. I placed the new ones in the 2nd slot, right above the first pair. The next pair will go below the upper-mids, and after that I will put a pair at the top of the lower mid-range, which would be the the 5th. one down.

In listening with the second pair in, I hear the same results as with the first pair, but more so. In other words, the difference between the original Infinity Emim's and the Graz replacements, is greater depth and clarity, with a large increase of everything sounding like their real selves. I can hear details inside the ensemble with a natural un-hi-fi sense of reality and timbre that I have never heard from my speakers before.

The ribbons play loud passages without any strain. Trumpets, for example have body, and sound like real instruments.

The greatest gain overall, is that the timbre of instruments reflect what they sound like in real life. You hear not just the central timbre of the instruments, but the overtones as well, which is what makes them sound so real.

I have a CD (although most of my listening was on vinyl) on Telarc of Clark Terry in a live performance-the audience is very involved in the recording, and when they applaud I can hear the individual hand-claps with a roundness and sense of space that was not there before.

I am a happy dude.

Bill

 

[BOB TAYLOR]

opinions please?
what is the best way to repair/replace the emins and emits on rs1bs????
replace with BG, Monsoon or Graz??

 

[Maxamillion]

In my opinion, it is not even close.

The BG and Monsoon "solutions" involve fitting something that is not, and never will be, an EMIM, into an Infinity speaker. These drivers do not have the same look, nor do they have the same behavior as an EMIM.

The Graz solution involves replacing the diaphragm of the EMIM with a far superior Apogee ribbon which Graz has optimized for the EMIM - he has spent many hours tweaking his solution to blend it into the overall Infinity sound. The Graz-ed EMIM looks like the original (except for the rippled and delaminating traces!) and does not require any modification to the rest of the speaker to work - it is truly a drop-in upgrade. As far as the sound goes - well read all about it in this thread and several others on this forum. To date I have not seen a negative review.

Of course the choice is yours, but I believe that Graz-ed Infinities will be far more valuable in terms of resale as well (if you could bear to part with them, that is...).

 

[bastek]

From what i hear the Graz Emim is closer in quality to the later Infinity HE Emim used in (single Emim) Renn. and last IRS series, which is truly an excellent midrange transducer. I hope when the time comes, something like that will be available for my beloved Sigmas.