Crossover experts Monitor 10 crossover question

[geppy1]

It appears from the 5 or 6 pairs of Monior 10 crossovers I have looked at(serial between 70,000 and 123,000) they all have the same cap values and same resistor values (2.7 and 2.5) This incudes early 10s (Denmark Peerless) 10As (US made Peerless) and early 10Bs (SL1000) The only difference is they started switching to electrlytics in 83. I have a pair of early 10B crossovers one is one type of cap the other has electos.

Here is my question Below is a picture of a 10A crossover (which i believe my early 10 looked like) and one of mine from my early 10s. About 17 years ago i was talking to ken (the man) at Polk and he said just send me your crossovers. He redid them The one with the big yellow caps are the ones he redid. The values are the same but he used a different type of cap in one postion and the resistor is a very long 2.7 and then a 2.0 not a 2.5 What did he really do here?? I would like to understand 1) The one cap change 2) the long 2.7 and 2.0 verse the short 2.7 and 2.5 on the priginal Thanks,keith

[FTGV]

What did he really do here?? I would like to understand 1) The one cap change 2) the long 2.7 and 2.0 verse the short 2.7 and 2.5 on the priginal Thanks,keith

1)Used a higher quality cap
2)The longer resistors will be higher wattage and there will be slightly less hi frequency attenuation with the 2.0 vs 2.5 ohms.

[geppy1]

I figured the cap was bettetr. I can never remember which is mylar and which is silver mica The yellow or the black and red?? If?? i wanted less high frequencies i would replace the 2.0 with a 2.5??

[FTGV]

I figured the cap was bettetr. I can never remember which is mylar and which is silver mica The yellow or the black and red??

The yellow ones are Mylars and I assume the black ones are electolytics.There are no Silver Mica's in this xover but they are usually brown and are only available in very small values.

if I wanted less high frequencies i would replace the 2.0 with a 2.5??

Yes but .5 ohms will only amount to a fraction of a db in level change.Also here the resistor has a capacitor in parallel with it which forms a contour network.The capacitor effectively limits the range over which the resistor will attenuate the tweeters output.The result being that the highest frequencies will not recieve the same amount of attenuation as the lower frequencies in the tweeters operating range.This would compensate for a rolled off top end in the M10 tweeters response.e .

[geppy1]

Bottomline, overall in theory how would this crossover change the sound compared to the stock one?

[FTGV]

Bottomline, overall in theory how would this crossover change the sound compared to the stock one?

In theory the better cap should improve hi frequency detail.The higher wattage rating on the resistor will make no difference.And IMO since the .5 ohm reduction in resistance equates to only a fraction of a db difference in level it should be imperceptible.

[geppy1]

Then it appears that he upgraded them slightly?? I am sure he had the choice to put in a 2.5 but must have had a reason for putting in the 2.0 and that type of cap where he did.

[Outfitter03]

Spam Post Reported.

[geph0007]

What does that mean??

[NotaSuv]

Spam Post Reported.

?????????????

[dcmeigs]

If it was done at Polk, don't you suppose they used the caps they had in inventory for their current production? Caps drift in value and fail altogether in time. I think they identified a bad cap and changed it. If the values are close but not exactly the same I think it's because that was the value they were using for current production.

[pitdogg2]

you had a spam infiltrater after post #7 it got zapped

[jcandy]

If there is someone in the San Diego/Irvine area who would like a significant crossover makeover for their vintage Monitor series (5jr, 5,7,10) speakers, I'm willing to donate my time and measurement equipment in order to do a complete redesign. The goal would be to do more than simply replace L/C/R components with new, higher-quality parts. Rather, I would try to improve the actual filter properties (by reducing the woofer inductor DCR, adding some contouring to the tweeter HP section, etc). Its no-risk, because you could keep the old crossover and swap the new one in/out as desired.