My Excellent RS1 Adventure

[slimpikkins]

Great story and thread. You will like the Mundorf mkp caps. I used them in my RSIIb with great success. Good luck sorting them out.

 

[pauljh]

I had a 350uF cap to replace in my Acoustic Research AR90s. I didn't want to build up poly's for that either. So, I bought a Mundorf 330uF E-Cap NPE, and paralled it with a 20uF Axon poly. So far, so good. Parts Connextion sells both brands. Or, check out Sonic Craft. No Axon's, but they have the Mundorf NPE's and poly's. Cheaper than Parts Connexion too.

I just had a look at the Mundorf 220uF bi-polar E-Cap and it is only rated 26v AC. That’s a bit too close for comfort.

 

[StimpyWan]

The RS1 ships with an external electronic crossover which (or some other external crossover) is required to run the system. The high pass section of the crossover, however, is passive. So it is possible that it was designed to work in conjunction with the high pass filter in the mid/tweeter towers. I think, though, that the major function of the speaker high pass low-EMIM filter is protection.

I seem to recall reading, that the Infinity external crossover is indeed passive on the high pass output. The dual high/low outputs were only there as a convenience to owners, without preamps with dual outputs. The main reason for the crossover is for it's low pass filtering and bass EQ. While not a servo system, it definitely improved the bass tower's performance.

 

[StimpyWan]

I just had a look at the Mundorf 220uF bi-polar E-Cap and it is only rated 26v AC. That’s a bit too close for comfort.

That's 26V AC, but 63V DC, which is what it would see in a speaker crossover. Plus, if it's paralleled with a poly (like I did), that would bump the DC rating too, as most polys are typically 250 VDC, or higher. The Axon I used with the E-Cap was 250V DC.

 

[kurtgo]

CDFAC rebuilt my crossovers on my RS1a's and did a great job - including the external crossover. He might be an additional resource for you as well.

 

[pauljh]

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CDFAC rebuilt my crossovers on my RS1a's and did a great job - including the external crossover. He might be an additional resource for you as well.

Thanks for the pointer. I’ll keep this in mind, but so far, I’m enjoying working on this project myself.

 

[pauljh]

Here are some pictures of EMIT and EMIM abuse, and how I take apart EMITs to replace diaphragms.

 

[totem]

how I take apart EMITs to replace diaphragms.

What are you replacing the OEM diaphragms with?

 

[pauljh]

What are you replacing the OEM diaphragms with?

I’m only replacing EMIT diaphragms. The EMIT in the photos is a 490125 thick EMIT. I took the diaphragm out of a thin 490123 EMIT I bought off of eBay.

As far as I can tell, all of the mid ‘80s EMITs use the same diaphragm; 490123, 490124, 490125, 490126, 9023082, 9025002, 9025023, and 9025086 should all be the same, though I haven’t taken all of them apart yet to prove my theory.

 

[pauljh]

That's 26V AC, but 63V DC, which is what it would see in a speaker crossover. Plus, if it's paralleled with a poly (like I did), that would bump the DC rating too, as most polys are typically 250 VDC, or higher. The Axon I used with the E-Cap was 250V DC.

I’m pretty certain that the signal in a speaker crossover is AC. That said, 26v AC into a 4 ohm load is about 110 watts, so it’s probably safe to use something of that rating. However, Solen makes a line of high value metalized polypropylene capacitors, so I’ve ordered a 200uF and a 51uF and I’ll use those.

 

[StimpyWan]

I’m pretty certain that the signal in a speaker crossover is AC. That said, 26v AC into a 4 ohm load is about 110 watts, so it’s probably safe to use something of that rating. However, Solen makes a line of high value metalized polypropylene capacitors, so I’ve ordered a 200uF and a 50uF and I’ll use those.

You might be right! . It does take a +/- waveform to create sound! . It sounded good in theory, to my addled brain anyway.

Good to hear about the Solens. They should work well. But if budget is tight, just use poly caps for the series values. They have the greatest audible impact. Then use NPEs for the parallel shunt positions. That shouldn't cause any issues. Though, I have to admit, in my AR90 recap, I used Mundorf EVO Oil & Supreme poly caps in the series positions, and Axon poly caps for the parallel shunts. Those, and the E-Cap and Axon bundle, for the 350uF bass shunt. I wasn't going into them again, after that. I figured, why not?

 

[pauljh]

I’ve also ordered some 47uF Mundorf polypropylene caps, so for the 250uF series cap I’ll use a 200uF Solen MPP in parallel with a 47uF Mundorf MKP PP, and I’ll use the 51uF Solen MPP for the shunt capacitor in the same circuit

 

[StimpyWan]

I’ve also ordered some 47uF Mundorf polypropylene caps, so for the 250uF series cap I’ll use a 200uF Solen MPP in parallel with a 47uF Mundorf MKF PP, and I’ll use the 50uF Solen MPP for the shunt capacitor in the same circuit

Mundorf MKF's? I've never heard of those? Do you mean the MKP's? If so, they're said to be very nice sounding. Very dynamic. I was very undecided between using the MKP's and the EVO Oil's. But, I went with the EVO Oil's, since they're supposed to be a very good vocal capacitor, which was what I was looking forward to enhancing even more so, in my 90's.

 

[pauljh]

Mundorf MKF's? I've never heard of those? Do you mean the MKP's?

Oops, yes, I meant MKPs. I’ll correct my mistake.

 

[StimpyWan]

Oops, yes, I meant MKPs. I’ll correct my mistake.

That's better than my AC/DC flub.

Oh yea, do you have any of the poly caps yet? MUCH, much bigger than NPE's. I hope they fit?

 

[pauljh]

I have the vast majority of the capacitors here sitting a box waiting. Unfortunately, three of the four Mundorf 47uF caps were out of spec and went back to Parts Connexion for replacement, which they are graciously attending to.

 

[StimpyWan]

I have the vast majority of the capacitors here sitting a box waiting. Unfortunately, three of the four Mundorf 47uF caps were out of spec and went back to Parts Connexion for replacement, which they are graciously attending to.

I was worried about the capacitors matching their stated values. So, I paid for parts matching, on my Mundorfs, at Sonic Craft. It helped with my compulsive nature, when spending that kind of money. And I didn't have a capacitance meter!

 

[pauljh]

Most (not all) of the capacitors have been fine. The inductors are all over the place.

 

[Bahamayellow]

Very nice setup.

 

[geoff727]

Most (not all) of the capacitors have been fine. The inductors are all over the place.

I have yet to measure large-value inductors used in Infinitys that are anywhere close to where they should be. I don't know why this is. Your experience too?
G~