Non polar electrolytic capacitors are extremely low distortion, comparable to the best polypropylene. Suggest you read the following https://linearaudio.nl/cyril-batemans-capacitor-sound-articles .
Against that, why get twisted out of shape about the non polar electrolytic? And what is the problem with the ceramic bodied resistors? They are used in most power amplifiers as emitter resistors in the power transistors. So where do you stop? Where do you draw the line?
Hey - why stop at the crossover. Surely the place to start is the amplifiers with hundreds of bog standard resistors, electrolytic capacitors and ceramic bodied resistors.
But what do I know? After all, I only ran technology at one of the largest loudspeaker manufacturing companies around.
Change what you like - I've had my say - and I'm going to unflollow this thread.
Against that, why get twisted out of shape about the non polar electrolytic? And what is the problem with the ceramic bodied resistors? They are used in most power amplifiers as emitter resistors in the power transistors. So where do you stop? Where do you draw the line?
Hey - why stop at the crossover. Surely the place to start is the amplifiers with hundreds of bog standard resistors, electrolytic capacitors and ceramic bodied resistors.
But what do I know? After all, I only ran technology at one of the largest loudspeaker manufacturing companies around.
Change what you like - I've had my say - and I'm going to unflollow this thread.
Will read it !
Non polar electrolytics in my previous speakers were a bit off. In the left one 6.8uF was measuring 5.4uF, on the right one 7.1uF. Similar for the midwoofer. Isn't this going to influence the crossover points to a margin that one can hear the result?
I did upgrade them with reasonable benefits. The new ones were exact at values. I got more details, tighter bass+details and more open sound. So again, now I'm curious what will be the result if I use higher grade parts on a better speaker?
Where do I draw the line? Wherever this hobby leads me to, and whenever my wife cuts off my HiFi financing! 🙄😀
And I didn't mean to upset anyone! I'm doing this for fun, not to argue or fight. Feel free to unflollow.....
Non polar electrolytics in my previous speakers were a bit off. In the left one 6.8uF was measuring 5.4uF, on the right one 7.1uF. Similar for the midwoofer. Isn't this going to influence the crossover points to a margin that one can hear the result?
I did upgrade them with reasonable benefits. The new ones were exact at values. I got more details, tighter bass+details and more open sound. So again, now I'm curious what will be the result if I use higher grade parts on a better speaker?
Where do I draw the line? Wherever this hobby leads me to, and whenever my wife cuts off my HiFi financing! 🙄😀
And I didn't mean to upset anyone! I'm doing this for fun, not to argue or fight. Feel free to unflollow.....
Yes, I've also achieved excellent results with certain electrolytics on tweeters. OP makes an interesting point..
..that it's the design and the values of the crossover that make the differences.
Interesting measurement. Certainly that wide a variation (-20%, +4.5%) is too large, but alas typical for electrolytic capacitors, Good that the replacements were well matched.
At one stage I had a pair of Martin Logan Aerius speakers. (long sold). The non-polar capacitors they had used in the crossover were physically small and underrated, and had vented their contents on the circuit board, New, physically much larger ones revolutionised the speakers. After cleaning the goo off the board that is.
So although I waxed lyrical about low distortion in non-polar electrolytic caps (that much is true), there are two provisos - matched values and sufficiently highly rated for current. And getting the often weird values in crossovers needs a bit of care.
And yes indeed we do this for fun!
The measurements were very interesting and i still got the old part at me. It was an entry level speaker from HiFi company. In practice the two speakers had different crossover points for both drivers. For me that is not ok and obviously it influences the sound.
Sound wise Q950 is a better speaker overall in stock condition. I hope that soon I will have spare time for DIY and improve the sound with the new parts.
Sound wise Q950 is a better speaker overall in stock condition. I hope that soon I will have spare time for DIY and improve the sound with the new parts.
That's good.
When you say the crossover frequencies were different, is it possible the drivers were doing their own thing and needed different leanings on each side to match up? I'm not suggesting this alone makes a perfect speaker, but it's is typically necessary to use different rolloffs on each side.
When you say the crossover frequencies were different, is it possible the drivers were doing their own thing and needed different leanings on each side to match up? I'm not suggesting this alone makes a perfect speaker, but it's is typically necessary to use different rolloffs on each side.
I did not measure the response but I assume they will be different.
First time I hear the need to correct every single speaker specifically for the transducer in them. I guess no one will put such an effort. And again the two capacitors were both rated 6.8uF and measured with big tolerance.
First time I hear the need to correct every single speaker specifically for the transducer in them. I guess no one will put such an effort. And again the two capacitors were both rated 6.8uF and measured with big tolerance.
Sometimes the crossover can be adequate but the overall tone can be out. To tell the difference I like to do a little equalising to investigate, trying to fix the issues to find out which ones are resistant to being fixed.
That is ok if you DIY or build hand made small batch speakers maybe.
For mass production I do not think this is the way?
For mass production I do not think this is the way?
Back in the early 90s I used to be CTO of Wharfedale. We used to churn out 50,000 pairs of Diamonds per annum. And an equal number or more of other speakers.
In that volume you cannot faff about. Crossovers were designed and small variants listened to in mono, blind, to fine tune. Then produced in massive batches.
In that volume you cannot faff about. Crossovers were designed and small variants listened to in mono, blind, to fine tune. Then produced in massive batches.
Hi, it stand 3W in free air and 30W with heatsink. Your oem resistor is a 5W, so I will go for a heatsink. But you dont need the big one that you can bye with the Mundorf. You can make you yourself one made of 2mm copper or aluminium. Make it as the width of the resistor and twice the hight or twice the with and oem hight or do both. Then you be fine.
Thanks, I have small aluminum heat sinks left from desktop PC RAM modules. I think they will work. The dissipation area is bigger that the suggested.
Yes - use a heatsink. The problem with power dissipation specs for any resistors is in free air. Likewise on a heatsink. In a speaker cabinet however, it is not in free air. So you need to over specify the heatsink.
Those Mundorf resistors look really good. Copper Manganin is a resistive material that has almost zero temperature coefficient. In other words the resistor value does not change much at all as it heats up. 50ppm/C is very good for any resistor - let alone a power resistor.
Ignore all the blah about sonic stuff in the spec sheet - the important thing is the temperature coefficient.
However - forget even that. A loudspeaker voice coil is wound with copper wire. In addition a loudspeaker is only about 1% efficient. That is because the motional impedance of the driver is very very different to the air impedance. So for 1 acoustic watt (that is very loud, by the way) you have to put around 100W into the driver, and 99W just heats up the voice coil.
Now the winding wire in a voice coil uses high temperature insulation, because it can get to 150C plus.
Copper has a thermal coefficient of resistance of ~0.4% per C (so 4000 ppm/C!). So at 150C an 8 ohm voice coil will be 8.6 ohms.
That alas swamps any benefit from a highly specified resistor by a factor of at least 80 times.
Don't get me wrong - I'd use the Mundorf resistors in a heartbeat if an application needed one. But in a loudspeaker crossover, not so much benefit.
Sorry to be a pooper on this!
Those Mundorf resistors look really good. Copper Manganin is a resistive material that has almost zero temperature coefficient. In other words the resistor value does not change much at all as it heats up. 50ppm/C is very good for any resistor - let alone a power resistor.
Ignore all the blah about sonic stuff in the spec sheet - the important thing is the temperature coefficient.
However - forget even that. A loudspeaker voice coil is wound with copper wire. In addition a loudspeaker is only about 1% efficient. That is because the motional impedance of the driver is very very different to the air impedance. So for 1 acoustic watt (that is very loud, by the way) you have to put around 100W into the driver, and 99W just heats up the voice coil.
Now the winding wire in a voice coil uses high temperature insulation, because it can get to 150C plus.
Copper has a thermal coefficient of resistance of ~0.4% per C (so 4000 ppm/C!). So at 150C an 8 ohm voice coil will be 8.6 ohms.
That alas swamps any benefit from a highly specified resistor by a factor of at least 80 times.
Don't get me wrong - I'd use the Mundorf resistors in a heartbeat if an application needed one. But in a loudspeaker crossover, not so much benefit.
Sorry to be a pooper on this!
sawyers: dont be a pooper ( : What is your first choice in resistor for tweeter? Maybe that Pockobg even feel that the Mundorf be to bright for his ears, he just have to try. Its all about what YOU like.
Frank
Frank
It's interesting to hear the opinions of one who was once involved in the real world of manufacturing speakers.
Even Wharfedale's new Diamond 12 budget range (developed in collaboration with Karl-Heinz Fink) employs quality crossover components.
It has little relevance by comparison with tens of meters of bog standard copper winding wire in the driver itself.
sawyers: I see, but people hear difference when changing components. But not all, that is how it is. Some hear micro things of change in there stereo, and some do not hear difference what ever you serve them. So, a drawback for us that hear difference in swapping components is that it can be expensive testing and buy. But when things match, its so fun. And the plus for us that do not hear changes, saving allot of money and happy with what they have.
Frank
Frank
Why have you not mentioned the third type of situation..?
This is when you can hear a difference and you know the reason for it. For example the ESR of a capacitor changes the response of the crossover. The problem this time is not the capacitor, it is the way you used it..