People have used resistance to tailor system response for years, whether it be with highly resistive wire, inserting a resistor etc. It's most commonly seen when someone is using an inherently well-damped wideband drive unit in combination with an amplifier of low output impedance. Many releatively high efficiency wideband drive units were designed / intended / expected to be used with a high output impedance amplifier; 2.5ohms series R is roughly akin to a typical SET amplifier for e.g., so deprived of this or some alternative form of Eq, they struggle in the LF regions. Using the published FE126En data as an example again, this results in effective driver Qe increasing from the nominal 0.33 to around 0.44, and Fhm dropping from 503Hz to ~377Hz, the reduction in electrical damping thus resulting in greater LF gain.
So in point of fact, as has been pointed out above, the output impedance of an amplifier can be too high / its damping factor too low in certain circumstances resulting in a sub-optimal system response; something which may be tailored by artificially adjusting the DF of the amplifier (or the Re, Qe etc. of the drive unit if you prefer) with some series R. Until the 1960s, it was common for amplifiers to have an adjustable output impedance to help optimise the speaker - amplifier match.
So in point of fact, as has been pointed out above, the output impedance of an amplifier can be too high / its damping factor too low in certain circumstances resulting in a sub-optimal system response; something which may be tailored by artificially adjusting the DF of the amplifier (or the Re, Qe etc. of the drive unit if you prefer) with some series R. Until the 1960s, it was common for amplifiers to have an adjustable output impedance to help optimise the speaker - amplifier match.
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So, just out of curiosity, is this what Dave and others are suggesting I buy to wire my speakers?
Amazon.com: 100ft Cat5E Certified Light Grey bulk cable - solid core: Electronics
Amazon.com: 100ft Cat5E Certified Light Grey bulk cable - solid core: Electronics
Yes. Very decent wire for next to nothing because we are riding on the backs of the billions of miles made for the computer world.
dave
Scottmoose, you sound well-informed. Is it possible to work out from the FE126En spec the optimum amplifier output impedance? Or does it depend on the speaker design?
Also, do you think that aiming for low output impedance and then using equalisation to raise the low end would be a better design philosophy than increasing the output resistance to boost the low end via reduced damping factor?
Also, do you think that aiming for low output impedance and then using equalisation to raise the low end would be a better design philosophy than increasing the output resistance to boost the low end via reduced damping factor?
One has to include the speaker & the room. It is very enlightening to hookup a variable transimpedance amplifier (output impedance dialable from close to zero to VERY high), and see what happens when you turm the knob. Each speaker tends to be happiest in a different place (each speaker around here, usually being a FR)
dave
Okay, I just bought that 100ft roll. I don't know what I'm going to do with the equivalent of 400ft of speaker cable...make a lot of speakers I guess!
On an unrelated note, anyone want to buy 350 feet of speaker cable?
well, you mean 3.5 x 100
also makes quite decent interconnect: stripping and untwisting the four pairs can take more time than building, and the RCA plugs, sleeving , heatshrink, etc will cost more than the cable for most often used lengths
I've run an unshielded spiral wrap I/C well over 12ft between a pre-amp and monoblock power amps that pick up less hum than the amp's self-noise.
For the past few days, I've been using a new interconnect fashioned out single strand Cat5 cables. Sound is better - HF, LF and details - all are there. And the improvement was palpable - we could hear the difference from the Monster interconnects and generic stuff that I have right away.
Thanks!
-Zia
You mean Indian music, Pat? It can sound truly great if it's recorded well. Unfortunately if you want to listen to the old masters you're pretty much doomed to listen to awful recordings. By the way, our friend Zia might be speaking Bengali since he's from Bangladesh... (I lived with a Bengali family for a year and all I learned to say was, "Maaaaaa....Cha hoy gache!")
(I lived with a Bengali family for a year and all I learned to say was, "Maaaaaa....Cha hoy gache!")Pit,
Chaz is correct, we in Bangladesh speak Bengali (Bangla), not Hindi.
Chaz,
Right again, the recordings of the old masters is a bit low-fi but they had great talent and skill. I tell my dad that it's such a loss that we don't have better recordings of their works...If we take a look at modern Hindi music, some of the stuff is very well recorded (and composed). A.R. Rahman's genius is well recognized.
So Chaz, did you like the "Cha"?
-Zia
Chaz is correct, we in Bangladesh speak Bengali (Bangla), not Hindi
.Chaz,
Right again, the recordings of the old masters is a bit low-fi but they had great talent and skill. I tell my dad that it's such a loss that we don't have better recordings of their works...If we take a look at modern Hindi music, some of the stuff is very well recorded (and composed). A.R. Rahman's genius is well recognized.
So Chaz, did you like the "Cha"?
-Zia
Zia, I should have remembered about languages - I´ve been told. Bangla = the language because the people are Bangla and therefore your country is Bangladesh =Banglaland? Correct me if I´m wrong, please.
And as to the cooking in your part of the world - wonderful. Provided one gets the ounces to grams spices conversion right.
And as to the cooking in your part of the world - wonderful. Provided one gets the ounces to grams spices conversion right.
Pit,
Bangla = Language of the Bengalis (the people), and yes "Desh" = Country, so Bangladesh would be Banglaland
. BTW, large number of peope (~50 million) in Eastern part of India also speak Bangla.Good to know that you like our cooking, and agree that spices are key to get the taste right; not much of a cook myself (SWMBO rules), but no slouch in the eating department.
-Zia
50 million plus the inhabitants of the country herself? One lives to learn, thanks for the info.
As to my language - don´t try. Spelling Donaudampfschifffahrtsgesellschaftskapitän
isn´t for the faint of heart.
Back to topic - your drivers have done a few hours by now. Are the harshness and the shout gone?
Pit
And what is SWMBO?
As to my language - don´t try. Spelling Donaudampfschifffahrtsgesellschaftskapitän
isn´t for the faint of heart.
Back to topic - your drivers have done a few hours by now. Are the harshness and the shout gone?
Pit
And what is SWMBO?
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no doubt he uses the term "mistress", when allowed to directly address her at all :wink:
my damn browser's still not letting me post smilies - that was a joke, Pit
Let's say, hypothetically, that some lazy individual wanted to use the solid core cat5 cable and merely stripped two of the leads inside the jacket and left the rest unused. Would there be any disadvantages (besides opulent waste) to this method for interconnects (line level as well as speakers)? I guess I, er, one would utilize one twisted pair per cable...
would utilize one twisted pair per cable...- Status
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