SL2000 response charts in sda compendium show no spikes
Comments
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Dammit H9, you had to copy/paste that techno-babble, didn't you!?!
Anyway, perfect answer. I'd have to say he missed the Stereo Review article.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
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Instead of bribing and theorizing to get to the end conclusion. The correct way to determine what is going on with the SL2000 tweeters is to make careful measurements of a physical sample. And they do not have to be anaechoic sine-wave sweeps. Gated burst tone measurements are mathematically equivalent and can be done almost anywhere. And as far as I know, there are no publically available distortion tests available either. We need these too.
Plots of the in-room response of the entire speaker system such as those found in magazines or done with your SPL meter in your living room are of limited utility, since the environment is not typically known or repeatable, and over-averaging can really skew the results. System tests also can't be used to extract accurate imformation about the drivers because of crossover electrical effects.
I have already started the process of measurements of the SL3000 tweeter and MW6510 woofer for my own purposes. I finished my impedance measurements already and will be able to extract the Thiel-Small parameters shortly. These will be as close to reality as one can get and not taken from fresh engineering samples built and measured in the mid 80's, but well-aged and broken-in units.
With respect to the tweeter, there are several things that can cause "sibilance", "peaking", "harshness", etc... From reading this board, the folklore here says we have a "spike", "peak", "bump" in the frequency response around 13kHz.
Instantaneous frequency response is only a superficial indication that a problem might exist. I will make "standard" frequency response measurements but also important are the following:
1. Stored energy in the tweeter response. Waterfall plots are useful in seeing this. e.g. A "peak" can sound bad, but a smaller "peak" will sound worse if it stays with the tweeter for several hundred milliseconds. I have the ability to test this. I've heard this called "linear" distortion.
2. Non-linear distortion. Also known as intermodulation distortion. These are basically mixing products (a non-linear effect) that happen when multiple-tones (as in music) modulate with one another and produce other tones. These "sub-tones" can be large compared to the desired tones and the odd-order tones are close in to the desired tones, which can make them the worst offending. This distortion is different depending on frequency and is always worse when operating a tweeter at too low a frequency. This is due to the non-linearities in the motor when there are large excursions. I can make this measurement as well.
3. And of course all the effects I listed above are power-dependent. I can test this but I won't. Too tedious. But the effect can be very significant as the voice coil heats up.
Cheers.
I like the first version better :mad: -
Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
"This message is hidden because ___________ is on your ignore list."
Ahhhh, the joys in life. That said, I'll see you folks tomorrow. I have a date with the pillow. Rock on!
~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~ -
Agreed.The correct way to determine what is going on with the SL2000 tweeters is to make careful measurements of a physical sample.
Yes for truly accurate measurements a computer based MLS,FFT setup is a must.Gated burst tone measurements are mathematically equivalent and can be done almost anywhere.
And its the frequency response that has the most influence on its actual SQ.frequency response is only a superficial indication that a problem might exist.
It all depends on the frequency range in which the energy is being stored.For example ,the same SEAS tweeter as I mentioned in previous posts has a very good performance with respect to CSD plots (waterfall).Everthing dies away fairly quickly except for the ultrasonic resonance which makes it ring like a bell at about 27k.However this is high enough so as to not cause audible problems,and this tweeter is highly regarded for it's clean detailed sound.But move that resonance an octave lower and it would be unlistenable.Waterfall plots are useful in seeing this. e.g. A "peak" can sound bad, but a smaller "peak" will sound worse if it stays with the tweeter for several hundred milliseconds.Testing
Testing
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So if I buy 8 RD098 for my SDA SRS ,what if anything do I need to change in the X over?
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So if I buy 8 RD098 for my SDA SRS ,what if anything do I need to change in the X over?
Nothing; they work with "stock" x-overs, as they are direct replacements. Many have replaced the aging caps and resistors in Polk speakers (as have I) with current production parts from Sonicap, Bennic, Dayton, Jantzen, Solen or Clarity Cap, and it takes the SDA's to a new level of refinement and enjoyment.
H9"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul! -
So if I buy 8 RD098 for my SDA SRS ,what if anything do I need to change in the X over?
If you have SDA SRS's or SDA SRS 1.2's you want the RD0194-1 tweeters. If you have SDA SRS 1.2TL's, then the RD0198-1's are what you want.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
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JonathanPeterson wrote: »Replaced sl2000 with rdo194.. still ear piercing harshness even at moderate volumes.. Bee gees vocal, some classical vocal music is unlistenable. Ears are ringing
The RD0194 is not a harsh sounding tweeter. What speakers and electronics are you using?Proud and loyal citizen of the Digital Domain and Solid State Country! -
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I would guess that it is time to rebuild your crossover networks. I only have experience with the Peerless tweeter though.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
JonathanPeterson wrote: »I tend to use bright or forward receivers but brightness is present with neutral receivers too
Speakers?
Proud and loyal citizen of the Digital Domain and Solid State Country! -
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What sort of interconnect and speaker cables are you using? Room type and acoustic treatments?George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
JonathanPeterson wrote: »Polk sda-crs+ (2 woofers one tweeter) with new film capacitors from parts express. Cross overs redone a year or 2 ago. Cross over update was a huge improvement. I listened to all original Polk sda-crs+ few months ago.. those sounded muffled and blurry compare to mine
Some film caps are also very screechy in the tweetet circuit. Please tell me you use a better cap there and not Solen or Dayton (Bennic) -
JonathanPeterson wrote: »Polk sda-crs+ (2 woofers one tweeter) with new film capacitors from parts express. Cross overs redone a year or 2 ago. Cross over update was a huge improvement. I listened to all original Polk sda-crs+ few months ago.. those sounded muffled and blurry compare to mine
Some film caps are also very screechy in the tweetet circuit. Please tell me you use a better cap there and not Solen or Dayton (Bennic)
Indeed, the Solens and the PE Dayton brand (Bennic OEM) are a bit bright -- good for refreshing old monkey coffins (i.e., replacing four decade old NP electrolytics) but not the best for hifi.
Good for the money they are, though. -
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Well didn't you say that your guests and musicians heard the same thing? Why didn't you hear the harshness right after you did the crossovers? Could it have been a bit of confirmation bias and then over time they became grating (maybe because they are?).
George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
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Oh my....LOLPolitical Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
I would well imagine they would be harsh or brighter in a room such as that. Imagine the reflections off the side walls! You should try some acoustic treatments especially at the first reflection points relative to your preferred listening position.
But you still didn't really answer about harshness "after" the crossover mod., relative to before. It is quite possible that you were accepting of that harshness and then over time reality sank in.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Is the interconnect wire in place?
Do all woofers move freely?Most people just listen to music and watch movies. I EXPERIENCE them. -
JonathanPeterson wrote: »Have to pull out cross overs to see what I put in there. Maybe my ears are young still. Overly sensitive to tremble. What's the average age of posters here
yea so lets now use ageism to help prove your point. If I did the crossovers I could tell you exactly what I put in there as I would of bought them and soldered them in. I can go back years and tell you every cap I've ever used and what I put them in. Polk did a lot of research to build the 194/198 tweeters so as NOT to make the same mistake they did on the SL2000 tweeters, it is well documented in the SDA compendium. @DarqueKnight is VERY knowledgeable and has done a lot of work here with a ton of research and spells it out with graphs I linked you to in the other thread. He also knew Matt Polk, Sandy and others very well as some others here. If you do not like them that is fine but why keep insisting we are all wrong and you are the only one who knows anything. @KennethSwauger is also very knowledgeable and has many threads here, he has worked for Polk a very long time but is no longer as active on the site as he used to be.
By the way according to my ear doctor my ears are very astute for my age and I'm a lot older than 35.
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Since you've abandoned your other thread I'll post this here as well.
get your read on
https://forum.polkaudio.com/discussion/182943/the-tale-of-5-tweeters-sda-tweeter-replacement-guide/p1 -
If your bass is floppy well that's a whole 'nother issue now. You probably need some good vibration isolation to remove the floor and the walls from the equation. Without that, you will be listening to those instead of your highly engineered speakers. Believe it or not, in my experience the highs are much cleaner also without extraneous vibrations from the outside world affecting the voice coil of the tweeter, like for example in a dorm room lol.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
This content has been removed.
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https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/26708.pdf
https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/26707.pdf
https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/26709.pdf
https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/26710.pdf
Really here are all of them.
Notice who put them together.... None other than @DarqueKnight
but yet we are all trolls posting gif's
DarqueKnight Posts: 6,629
August 2007 edited August 2007
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