SDA crossover upgrades

Toolfan66

The audio KING!!!!

DarqueKnight

oliverbubbles wrote: »

Man the guy i bought these from was right; there are some fu@$in idiots around this forum. There are also some decent people too. Joe and a few others appear to be some of the latter. The rest of you dumba$$es please treat me like you are treating Audio and ignore me.

Really ...Mr. Bubbles, swearing and vulgar namecalling on a family forum such as ours? It's very unbecoming.

oliverbubbles wrote: »

yeah i got that name for my bubbly fu@&!N personality. Fits pretty well doesn't it.

No. Not lately.

oliverbubbles wrote: »

Don't get me wrong they sound awesome and the cabinets are adequate for the drivers installed in them but the build quality on the ones I have seen sucks.

Yeah, I've seen some messed up SDA's with messed up cabinets...due to owner abuse. The cabinets of my SRS's and 1.2TL's are very good. Of the SDA's I have owned, the only ones where I had some issue with the cabinets were my CRS+'s. That was due to the "crumbly" nature of the particle board when drilling them to install steel driver retaining rings.

oliverbubbles wrote: »

But hey laugh all you want. If you ever come to South Carolina, look me up. Maybe we can have a beer and discuss things like real men.

Based on your conduct on this forum, I assume "discussing things like real men" includes lots of insults and cursing. Therefore, I will politely decline.

oliverbubbles wrote: »

I almost forgot, if you wish to respond to this again, fine. I am growing tired of the BS so I will let you have the last word as any "god" should be able to. I will not respond to you on this matter again.

OK. Good night Mr. Bubbles. It was nice chatting with you.

rromeo923

First of all you guys are mad geniuses as I dont understand half of what you all are talking about.

Second of all you guys are all crazed for getting into this heated discussion.

Third I am crazier for reading this entire thread.


Keep it up!!:biggrin::biggrin:

CNWDI

I'm really sorry I was busy elsewhere and missed this...entertaining discussion today. Someone should have told me to get online and bring the popcorn. Backing up several hours:

DarqueKnight wrote: »

I have attached a copy of the forward statement from the 1989 Polk Audio In Field Technical Manual. Warranty Manager Helen Yarbor states, in all caps (which is the written equivalent of screaming):

"IT IS IMPORTANT TO REALIZE THAT WE MANUFACTURE A VARIETY OF 6 1/2" DRIVERS WHICH ARE OPTIMIZED FOR SPECIFIC MODELS. THEREFORE IT IS HIGHLY RECOMMENDED THAT ONE READS THE QC STICKER ON THE BACK OF EACH DRIVER AND MATCH THE PART NUMBER TO ITS PARENT MODEL USING THE CROSS REFERENCE SUPPLIED IN THIS MANUAL."

The key point that I think DK has made several times is that if someone wants to make changes to vintage Polk speakers, Polk is remarkably supportive of inquiries. In fact, when I inquired about a month ago about RD0198-1 and MW65xx availability, the response came from...Ms. Yarbor. There are few companies that still have the same (quite knowledgeable) people dealing with issues 20+ years later...so regardless of any experience or degree I might have, I'd personally tend to ask Polk for at least a review of any significant modification plans (beyond replacing specific capacitors/resistors with updated high-quality components of the same impedance).
--CNWDI

inspiredsports

For Mr. Bubbles (before I put you on ignore), the following may help you determine why you can't arbitrarily switch crossovers:

Driver ........ Q ........ BL .... Compliance .... DC Res ........... Fs ...

MW6501 - 1.470 - 5.96 N - 3.250 E 3N/M - 7.750 Ohms - 31 Hertz
MW6502 - 1.970 - 5.16 N - 1.470 E 3N/M - 3.520 Ohms - 44 Hertz
MW6503 - 1.820 - 5.24 N - 3.550 E 3N/M - 6.540 Ohms - 29 Hertz
MW6509 - 2.100 - 4.57 N - 3.540 E 3N/M - 8.970 Ohms - 30 Hertz
MW6510 - 1.390 - 6.32 N - 3.410 E 3N/M - 6.570 Ohms - 31 Hertz
MW6511 - 1.405 - 4.34 N - 3.496 E 3N/M - 3.130 Ohms - 29 Hertz
MW6512 - 1.905 - 4.99 N - 1.588 E 3N/M - 3.466 Ohms - 40 Hertz

Cabinet design/bracing/volume and the exact version of the passive used also come into play.

TECHNOKID

oliverbubbles, I'd like to commend you on your OP and your effort to improve your speakers (however, it is very unfortunate that the thread turned out the way it is now. Who's guilty, I don't really care and will not comment).

There are design rules and which must be respected during the course of a modification.

The above quote is key, there are so many variables (mechanical, electrical, physical) that will make a speaker and this is best left to the engineers and the manufacturer that created a specific product. I really feel it would be in your interest to trust and seek Polk advices on mods you want to achieve as they can provide you with some valuable insight.

I do not know you so not sure where you would put your self but;

There are hobbyists:
"An activity or interest pursued outside one's regular occupation and engaged in primarily for pleasure." IMHO, a hobbyist has some skills, abilities and knowledge however, is not a specialist per say.

There are technicians: 1. A person employed to look after technical equipment or do practical work in a laboratory.
2. An expert in the practical application of a science.

However, IMHO the technician while having some skills they are somewhat limited to repair, maintenance and proven upgrades that are provided and approved by higher technical expertise.

Technologist: A specialist in technology. IMHO this is the guy that would attempt to do the type of modifications you are trying to attempt however; he would work closely and under the guidance of the engineer responsible for the project.

Engineer: A person who designs, builds, or maintains... IMHO, he is the creator (the god as you like to point out) that one (hobbyist, technician, technologist) would go to for guidance for any changes in design (IMHO, even a serious engineer would often refer to the creator of the design if intending to modify existing design).

Now, I am in no way trying to pick on you but 1st just want to know where you locate your self in this ladder? Secondly, IMHO it seems you are missing/miss-understanding the critical aspect of playing with the original value of each components of a design.

Personally, I am and I stop at the technician level. I know my abilities, what I can perform and exactly where I should stop and seek advices from the manufacturer. No big deal in most cases playing with series/parallel as long as the original values remain the same. No biggy replacing parts with better quality/newer technology as long as the original design is respected. No problem repairing and so on however, when it comes to altering the original design I realize this is not my place and if I have an idea I think that can improve or believe it will not affect the end result, I will not take my assumption for granted and will dare ask for advices at the engineering level. IMHO, you are to be commended for your effort to improve your speakers but IMHO, you would greatly benefit from seeking the creator (Polk) of your speakers.

Again, I commend you for your post, what you achieved so far and what you are actually trying to accomplish. Please keep us posted on your progress as I am very interested to see where this is leading you (good or bad). Life is a learning curve and I can definitely see this is exactly what you are doing/achieving.

Joe08867

oliverbubbles wrote: »

I apologize Joe, I do see that and i now see where the confusion is coming in. I have been describing this in "effective" terms as compared to each other instead of actual terms as you are here. That is my fault and i am sorry to have confused you. i may have also confised you in my answer to your previous question. so let me rephrase my previous answer; yes I am making adjustments to compensate for this actual difference.

H9, I think a big reason i like the 2's so much better is their simplicity and to me it shows in the sound as being less colored to my ears.

No problem at all, I just wanted you to look at the whole picture and not separate as you had been.

I apologize if I came off angry. I will admit I was getting perturbed but only because my explanation was being missed. Probably why I don't have children. :biggrin:

Your idea for a possible fix may in fact work so again I say good luck.

Marty913

Disclaimer: All my opinions, no real facts involved.

Mr. Bubbles,

In case you’re wondering why the “shields were raised” in this whole thread and it turned decidedly south around post #32, it may have more to do with the audience / forum chosen than anything remotely related to the technical points raised. It might be helpful if you considered the following:

The Polk Audio Vintage Speaker threads may appear to simply be a collection of people who enjoy sharing ideas about old Polk speakers (be that acquisition, design, modification, or the simple enjoyment thereof). It is in fact all that, but perhaps just a little bit more – particularly where SDA models are involved. In large part, this forum exists because there are many people here that view the Polk SDA series as one of the finest and most unique speakers ever made - a legacy to be protected in a world of background music, inferior products, and throwaway technology.

Not to get all religious on you but in some respects the few hundred members here are the “Knights Templar” of a product that they believe represents far more than just “technology to be redesigned”. Whether it can or should be is somewhat irrelevant. I personally believe the Sistine Chapel would look a lot better with some alternate paint choices but I’m having a hard time selling that over on the Vatican Forum. I guess there are just some lines that are best left uncrossed.

You have to look a lot deeper than technology to understand the family here. It does take a little time but its well worth the effort. I wish you personal success with your experiments and hope you share the results.

tpl12blk

Thanks so much for this! This is exactly what I was looking for

falconcry72

tpl12blk wrote: »

Thanks so much for this! This is exactly what I was looking for

reported.

Mr. Bubbles

Simply for the sake of anyone who may be interested; I updated the tweeter section of the crossover to match that of the 1.2 and IMO it made a significant IMPROVEMENT. The detail came out about 1/4- 1/3 as much again as upgrading the capacitors. Not a lot of listening on this yet and will see if this changes as the components break in. The tweeters now seem to be more closely in line with the mid-range, but still not quite there.

Mr. Bubbles

Ok, I started wondering if I wasn't just wanting to hear an improvement as I think many times we want our work to be validated so we make ourselves hear what we want. That being said I put the right channel back to origional and listened in mono to compare the treble in each cabinet. I then switched to stereo again and listened for any dimensional imbalance. I hadn't heard any effect on the dimensional sound with this mod but wanted to simply triple check myself. especially after all this BS. No effect on the dimensional sound, just as expected since the circuit is not tied to the dimensional drivers or circuit. The tweeters definitely sound better with the update. Cymbals sound more metallic. Tambourines sound more crisp. everything is less hazy or as I've read here before as a description; like a veil was removed.

evhudsons

"FrankenPolks", Hilarious!

I had a feeling that has been around for a while after reading DK's warnings. I googled it and read some really good stuff. Personally I would go mad changing out so many things that I couldn't just go back and quickly fix something to figure out what went wrong, especially if it was all wrong and you had to start over again from scratch.

But..great info. I had driver questions regarding the 6511 and 6503 and they were answered.

Note to Oliver: I think people are still interested in your outcome. I hope you have a fire extinguisher handy just in case you need a quick mod fix.

inspiredsports

CNWDI wrote: »

. . . the key point that I think DK has made several times is that if someone wants to make changes to vintage Polk speakers, Polk is remarkably supportive of inquiries. In fact, when I inquired about a month ago about RD0198-1 and MW65xx availability, the response came from...Ms. Yarbor. There are few companies that still have the same (quite knowledgeable) people dealing with issues 20+ years later...so regardless of any experience or degree I might have, I'd personally tend to ask Polk for at least a review of any significant modification plans (beyond replacing specific capacitors/resistors with updated high-quality components of the same impedance). . .

Paired with that, you also need the discipline to work within accepted speaker/crossover building practices, and that takes a huge committment of time and money.

You need to obtain and master software programs like ARTA/TrueRTA/REW/etc. and the learning curves are steep.

You need to learn if nearfield, 1 W@1 Meter or listening position measurements are needed, and how to neutralize modes if you are measuring from the listening position.

You need at least one high quality (preferably calibrated) omnidirectional mic, and two if you want to gather an accurate picture of how the room interacts with the speaker. You need DIN cables and mic booms, a decent DAC to send signal to your speakers and a decent USB Interface or approved internal soundcard to interface the mics.

Did I mention plotting impedance curves?

Without the ability to measure with more than your ears, you are taking a shot in the dark at a black needle in a black haystack.

I'm a huge proponent of listening, but when modding speakers accurate data is a must.

heiney9

oliverbubbles wrote: »

Simply for the sake of anyone who may be interested; I updated the tweeter section of the crossover to match that of the 1.2 and IMO it made a significant IMPROVEMENT. The detail came out about 1/4- 1/3 as much again as upgrading the capacitors. Not a lot of listening on this yet and will see if this changes as the components break in. The tweeters now seem to be more closely in line with the mid-range, but still not quite there.

oliverbubbles wrote: »

Ok, I started wondering if I wasn't just wanting to hear an improvement as I think many times we want our work to be validated so we make ourselves hear what we want. That being said I put the right channel back to origional and listened in mono to compare the treble in each cabinet. I then switched to stereo again and listened for any dimensional imbalance. I hadn't heard any effect on the dimensional sound with this mod but wanted to simply triple check myself. especially after all this BS. No effect on the dimensional sound, just as expected since the circuit is not tied to the dimensional drivers or circuit. The tweeters definitely sound better with the update. Cymbals sound more metallic. Tambourines sound more crisp. everything is less hazy or as I've read here before as a description; like a veil was removed.

So I have to ask, are you using old caps or new caps? Because if you are using new caps for the 1.2TL tweeter circuit config and the original caps for the SRS tweeter circuit then the improvements you hear are more than likely from the new vs. old caps. I believe you stated you didn't do the tweeter section because you were waiting to change it over to a 1.2TL, and I assumed you meant with new caps. So if you are switching back and forth between original and 1.2TL that means you spent twice as much on new caps and resistors so you can compare both ways with fresh caps, not old caps vs. new caps. I ask because you didn't make that part of the experiment clear at all. You stated you were on a budget and this was a budget tweak, but to compare them properly you have to spend twice as much.

Also much of the improvements you hear with better integration are probably related to the new caps you used in the low pass. You see your experiment might be flawed because you really haven't isolated a control part of your upgrade, so while I don't discount you hear differences, I am nit inclined to attribute them solely to the 1.2TL tweeter circuit mod, because so far, based on how you explained it, there is no way to know for sure that's what's causing the improvement.

The way it should have been done is to leave everything else alone and use the exact same brand new caps and resistors for both the SRS and 1.2TL tweeter circuits, changing nothing else and after 300-500 hours break-in for both configurations then the sound should be analyzed. Same music, same source, same listening position, etc, etc, etc.

H9

Mr. Bubbles

heiney9 wrote: »

So I have to ask, are you using old caps or new caps? Because if you are using new caps for the 1.2TL tweeter circuit config and the original caps for the SRS tweeter circuit then the improvements you hear are more than likely from the new vs. old caps. I believe you stated you didn't do the tweeter section because you were waiting to change it over to a 1.2TL, and I assumed you meant with new caps. So if you are switching back and forth between original and 1.2TL that means you spent twice as much on new caps and resistors so you can compare both ways with fresh caps, not old caps vs. new caps. I ask because you didn't make that part of the experiment clear at all. You stated you were on a budget and this was a budget tweak, but to compare them properly you have to spend twice as much.

Also much of the improvements you hear with better integration are probably related to the new caps you used in the low pass. You see your experiment might be flawed because you really haven't isolated a control part of your upgrade, so while I don't discount you hear differences, I am nit inclined to attribute them solely to the 1.2TL tweeter circuit mod, because so far, based on how you explained it, there is no way to know for sure that's what's causing the improvement.

The way it should have been done is to leave everything else alone and use the exact same brand new caps and resistors for both the SRS and 1.2TL tweeter circuits, changing nothing else and after 300-500 hours break-in for both configurations then the sound should be analyzed. Same music, same source, same listening position, etc, etc, etc.

H9

I had originally updated all of the tweeter crossover components except for the 97uf shunt cap. When that update was done it made a HUGE difference/ improvement. Just as expected. I also updated all stereo and dimensional caps and resistors except the high-pass circuit for the interconnect. 2nd mod was simply to update the tweeter circuit to the 1.2. NOT the 1.2TL. The second mod created an additional unveiling over changing the caps and resistors. I have no plans in the near future to go to the TL in these speakers. I just wanted to hear the difference in the tweeter section between a SRS and 1.2. I do not have 1.2's but have changed the components in my SRS's tweeter section to match that of the 1.2's. To me it sounds much better and I will be using them in this configuration. The tweets are no louder but the instruments sound more detailed and realistic.

heiney9

Ok, still doesn't answer my questions. I know you changed between the SRS and 1.2. A simple yes or no will suffice to my questions. Also I didn't mean 1.2TL, that was my error. I meant original SRS and SRS 1.2. Ignore the 1.2TL as it's a typo/brain ****.

H9

inspiredsports

This thread is becoming more and more mystifying . . .

The initial premise (in fact the first sentence) was, "This post is not really for you "hardcore" guys out there with unlimited budgets but more for the guys on a budget considering crossover upgrades."

Yet now it spans multiple upgrades to multiple crossovers, plans to TL which requires at least 8 new RDO drivers, and no deference to the already accumulated knowledge base that would actually make a cost-efficient, champagne-on-a-beer-budget, upgrade possible.

Mr. Bubbles

H9, I am not clear on what your question is. None of the caps used have had time to break in yet. About 10 hours listening since updating all caps and resistors. then switch to 1.2 circuit. I am not sure how a yes or no would suffice. Yes it sounds better to me, no I don't care if anyone else on here likes the idea or not.

Inspired, please stop acting like my wife and getting only the part that works for you, or put me on ignore like you said you were gonna.

Toolfan66

I have yet to understand why one would waste the time and energy to do this. Why not just buy a set of 1.2/1.2tl's ooohh thats right we are on a budget but i am going to waste my time and money on something that may or may not work.

IMO if these speakers do not give you what your looking for then sell them and try something else..

either way they are your speakers so good luck with them!!!

inspiredsports

oliverbubbles wrote: »

H9, I am not clear on what your question is. None of the caps used have had time to break in yet. About 10 hours listening since updating all caps and resistors. then switch to 1.2 circuit. I am not sure how a yes or no would suffice. Yes it sounds better to me, no I don't care if anyone else on here likes the idea or not.

Inspired, please stop acting like my wife and getting only the part that works for you, or put me on ignore like you said you were gonna.

I changed my mind.

Are you anywhere near NE Ohio? I'd be glad to bring my calibrated Behringer's, Alesis io2 Express, boom tripods and analysis software laden laptop over to show you all of the massive hills and valleys you've created.

Mr. Bubbles

Without the ability to measure with more than your ears, you are taking a shot in the dark at a black needle in a black haystack.

Awwww, you make me feel special. I didn't realize that I was one of so few that has ears than when they hear something are tied to a brain that actually tells them if they like it or not. But I actually have that ability. I am sorry for you but don't worry, just because you can't ride the short bus anymore doesn't mean that you aren't special too. I am glad you have the hearing equipment you need.

inspiredsports

oliverbubbles wrote: »

Awwww, you make me feel special. I didn't realize that I was one of so few that has ears than when they hear something are tied to a brain that actually tells them if they like it or not. But I actually have that ability. I am sorry for you but don't worry, just because you can't ride the short bus anymore doesn't mean that you aren't special too. I am glad you have the hearing equipment you need.

You've missed so much of what I've written.

I place a huge value upon listening and listen for the pure artistic enjoyment of it most of the time, but when you start making massive changes to the fundemental components of a speaker design you simply can't do it with ears alone.

If you would take the time to learn how Polk designed/designs speakers (or any speaker designer designs speakers), you'll realize you have no chance of doing it properly with your ears alone.

You may get an over-compensated bottom and top end (the classic "smiley" curve) that sounds appealing to some, but you are simply pissing on dozens of successful careers and hundreds of thousands of R&D dollars. Statistically, you don't have a chance of being "right".

But, I do respect your right to experiment and please yourself, even if others may not agree.

Next Polkfest (2013) at your place?

evhudsons

If someone offers to help even if that means showing you the obstacles that may lay ahead then that person is not an ****. I'm interested in the FrankenPolk thing and I have yet to see one long time Polk forum member respond as an ****. I think they would rather not respond at all if they were so inclined to be an ****. Just my .02 which sometimes doesn't get much on the karma exchange rate.

Face

oliverbubbles wrote: »

Awwww, you make me feel special. I didn't realize that I was one of so few that has ears than when they hear something are tied to a brain that actually tells them if they like it or not. But I actually have that ability. I am sorry for you but don't worry, just because you can't ride the short bus anymore doesn't mean that you aren't special too. I am glad you have the hearing equipment you need.

[Sarcasm]I'm sure Polk didn't use any measuring equipment while designing them either.[/Sarcasm]

inspiredsports

Face wrote: »

[Sarcasm]I'm sure Polk didn't use any measuring equipment while designing them either.[/Sarcasm]

I just found this smiley icon, the "Lone Ranger" :loneranger:. Maybe Oliver should use it when he posts.

evhudsons

What is in the water lately? There sure seems like a sudden surge in DB's on this forum. To a point it's entertaining, well, not really. Several lone rangers running amuck. I understand if it were a bunch of knowitall preteens but these are grown adults. Oh well it's a forum.

AndyM23456

I’m confused as hell after reading all of this. I have a set of 1.2’s and a set of 1.2tl’s I’d like to recap/re-resistor, for the best sound I can get from them.

Is there a definitive list of the components I should buy to start desoldering/resoldering?

Thanks,
Andy

F1nut

A definitive list of the components? Not really as there are multiple options. I suggest you read more than this thread.

pitdogg2

AndyM23456 wrote: »

I’m confused as hell after reading all of this. I have a set of 1.2’s and a set of 1.2tl’s I’d like to recap/re-resistor, for the best sound I can get from them.

Is there a definitive list of the components I should buy to start desoldering/resoldering?

Thanks,
Andy

Well, what many of us have over the years is that these capacitors work very well
Sonicap gen 1
Clarity, depending on your cost restrictions low to high, PX, ESA, CSA, MR and CMR
As for resistors the two biggest are Vishay-Mills and Path
Other resistors have been
Mundorf
Jantzan
There's also inductor we've used
Jantzan have replaced most of the factory inductors with the same wire gauge, value and DCR.
SDA inductor Jantzan C-coil 14 gauge 16mH.

One of our members does work if you so choose.
@VR3, the guy makes art in the guise of a crossover