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Téma: poraďte-kondenzátor-tlumivka!!!!!!!!!!!
[dr.fefedebill]
poraďte-kondenzátor-tlumivka!!!!!!!!!!! -
Nástroje > Boxy a reproduktory
potřeboval bych poradit na co a jak se používá kondenzátor a tlumivka mělo by to nějak dělit zvuk(basy a vejšky)...případně poraďte jak to zapojit když mám basovou a vejškovou bednu a jeden vývod ze zesilovače!!dík
poraďte-kondenzátor-tlumivka!!!!!!!!!!! -
Nástroje > Boxy a reproduktorypotřeboval bych poradit na co a jak se používá kondenzátor a tlumivka mělo by to nějak dělit zvuk(basy a vejšky)...případně poraďte jak to zapojit když mám basovou a vejškovou bednu a jeden vývod ze zesilovače!!dík
Seznam příspěvků:
[martin2]
Re:
kondik oreze basy, tlumivka vysky. Napis presne co mas za zesilovac, co to je za bedny, cim osazeny, ...
Re:
kondik oreze basy, tlumivka vysky. Napis presne co mas za zesilovac, co to je za bedny, cim osazeny, ...
[nuclear]
Re:
ted sem nahodou narazil na takovej clanek.. myslim ze to bude to co ty potrebujes, rady k sestaveni vyhybky .. http://www.zesilovace.cz/view.php?cisloclanku=2003011601
Re:
ted sem nahodou narazil na takovej clanek.. myslim ze to bude to co ty potrebujes, rady k sestaveni vyhybky .. http://www.zesilovace.cz/view.php?cisloclanku=2003011601
[dr.fefedebill]
Re:
¨je to starej lampovej zesik z nějakýho radia...nic moc ale mě to stačí....výkon nevim ale tak kolem 50w...ty bedny maj 4ohm(ten zesik je na 5ohm bedny)..je to basová bedna 70w(až 140w)a vejškáč je to samý.......a eště z toho zesiku je jenom jeden vývod!!!
Re:
¨je to starej lampovej zesik z nějakýho radia...nic moc ale mě to stačí....výkon nevim ale tak kolem 50w...ty bedny maj 4ohm(ten zesik je na 5ohm bedny)..je to basová bedna 70w(až 140w)a vejškáč je to samý.......a eště z toho zesiku je jenom jeden vývod!!!
[nuclear]
Re: fefedebil
tudiz ten zesik musis zatizit minimalne 5ohmmy .. jestli to zatizis min tak spalis zesik i bedny... zapoj ty repra do serie a melo by to bejt ok.
Re: fefedebil
tudiz ten zesik musis zatizit minimalne 5ohmmy .. jestli to zatizis min tak spalis zesik i bedny... zapoj ty repra do serie a melo by to bejt ok.
[Jean]
Re: nuclear
Myslíš, že ten jeden překročenej ohm to může vodpálit? Dr.fefedebill je zvyklej "přeračovat" impedanci na svim domácim HiFi až na 1/2 povolený hodnoty a fachá mu to. Navíc je možný že vejškáč klade větší odpor basovejm frekvencím, takže když to zapojíš do série, nepujdou basi ani na basáku a naopak. Je to jenom moje hypotéza, nikdy jsem to nezkoušel, nevim.
Neni možný, že ty lampy začnou při nižší impedanci bedny taky zkreslovat?
Mějte se, Jean
Re: nuclear
Myslíš, že ten jeden překročenej ohm to může vodpálit? Dr.fefedebill je zvyklej "přeračovat" impedanci na svim domácim HiFi až na 1/2 povolený hodnoty a fachá mu to. Navíc je možný že vejškáč klade větší odpor basovejm frekvencím, takže když to zapojíš do série, nepujdou basi ani na basáku a naopak. Je to jenom moje hypotéza, nikdy jsem to nezkoušel, nevim.
Neni možný, že ty lampy začnou při nižší impedanci bedny taky zkreslovat?
Mějte se, Jean
[batty]
Re: nuclear
Pro 5ti ohmovej vystup zesilovace bude lepsi 4ohmy nez 8. Neshorel by ani pri jednom, ale hrat bude lepe to blizsi.
Re: nuclear
Pro 5ti ohmovej vystup zesilovace bude lepsi 4ohmy nez 8. Neshorel by ani pri jednom, ale hrat bude lepe to blizsi.
[nuclear]
Re:
kazdopadne se ti bude vic hrat trafo a nebude to dobry .. nevim jak o jeden ohm min ale kdyz to prezenes moc tak ti rikam ze to spalis.. njn.. s tema bednama to je shit..
Re:
kazdopadne se ti bude vic hrat trafo a nebude to dobry .. nevim jak o jeden ohm min ale kdyz to prezenes moc tak ti rikam ze to spalis.. njn.. s tema bednama to je shit..
[batty]
Re: prevzato z webervst
From: Chuck
I have heard various views on impedance mismatches between the amp and the speakers. One is that you should always match the impedance (4 ohm amp = 4 ohm speaker or two 8 ohm speakers in parallel), or you can blow your transformer. The other is that it is fine to mismatch, but you may lose power. Should the impedence match? If yes, then how quickly could you damage your amp when you have a mismatched impedence?
Chuck, technically, you should always provide a load that is recommended by the manufacturer of the amp. The designer of the amp chose a particular output device (tube) and specified all of the operating voltages for the output stage so the tube would work at its optimum efficiency while delivering maximum power to the load with minimum distortion. Ok, so let's discuss the problems associated with mismatches. When you use a load that is lower than the intended load, the output has to drive the load (speaker) with more current because it is a lower impedance than is expected. Two inherent problems associated with transformers are flux leakage and regulation. Flux leakage is also referred to as leakage inductance. It is related to the current in the secondary, and these problems increase as the current increases. As the current draw in the secondary increases, the primary has a more difficult time transferring the signal to the secondary, so the secondary signal to the load gets squashed, or 'soft-clipped'. This soft clipping is called regulation. While regulation is desireable in a power supply, it is undesireable in a transformer. In other words, in a power supply, if the input voltage or the output load current changes, we don't want the output voltage to change. In a transformer, we want the output voltage to follow the input voltage and not regulate at all. When you put a heavier load on the output than was intended, it will pull the output voltage down, hence regulation. The leakage inductance problem arises because the current from the heavier load causing the regulation to occur reduces the efficiency of the transformer by not allowing the output to follow the input. Transformer designers simulate or view this problem as having extra inductance in series with the primary. The extension of this idea then, is that with the heavier load, you could affect the efficiency of the transformer, alter the frequency response (due to the extra leakage inductance in series with the primary), and cause other distortions to occur. OK, on to mismatching the other way. A speaker is a current operated device in that it responds to the current through it to generate a magnetic field that works against the magnetic field of the speaker magnet to make the cone move in and out. Thinking in very short amounts of time, when the output charges up the voice coil with current, then the signal goes away or gets reduced, the cone system moves the voice coil back to its home or resting position. As it is moving back, it generates a voltage that is fed back up the line into the transformer and appears in the output circuit of the amp. This generated voltage is often referred to as flyback voltage, because we are charging up an inductor, then when we disconnect or stop charging the inductor, the magnetic field in the inductor collapses and induces this big voltage into itself. This big voltage then 'flies back' to the source of the charging current. There is a mathematical formula to determine how big the voltage is and it is related to the inductance of the voice coil, the amount of time it was fed current, and how much current it was charged with. The bottom line is that the voltage fed back to the output circuit is oftentimes much higher than the voltage that was used to drive or charge up the voice coil initially. This voltage gets transformed up by the turns ratio of the output transformer, and in many cases can be over 1,000 volts. What happens then is that arcing can occur between the pins on the output tube socket. Once this has occured, a carbon path forms on the tube socket between the pins. The carbon path allows a steady current to flow between the pins and eventually burns up the socket due to the heat that is generated. For example, it wouldn't be too uncommon to see a transformer turns ratio of 30:1. If we had a voltage fed back from the voice coil that was around 50 volts, 30 times 50 would be a 1,500 volt spike at the plate of the output tube. This is why you often see designers connect diodes in a string between the output tube plates and ground. They are trying to suppress these spikes and dissipate the energy in the diodes rather than allowing an arc to occur at the tube socket. So, when you use a higher impedance load on a lower impedance tap, the turns ratio is higher and resulting fed-back (flyback) voltage gets multiplied up higher than what it would have been with the correct impedance load.
It's just about impossible for me to answer how long an amp would last under these conditions. It all depends on how the designer took these potential problems into account in his or her design with regards to the quality of the tube sockets, the use of stringed diodes, the output circuit operating voltages, etc.
Re: prevzato z webervst
From: Chuck
I have heard various views on impedance mismatches between the amp and the speakers. One is that you should always match the impedance (4 ohm amp = 4 ohm speaker or two 8 ohm speakers in parallel), or you can blow your transformer. The other is that it is fine to mismatch, but you may lose power. Should the impedence match? If yes, then how quickly could you damage your amp when you have a mismatched impedence?
Chuck, technically, you should always provide a load that is recommended by the manufacturer of the amp. The designer of the amp chose a particular output device (tube) and specified all of the operating voltages for the output stage so the tube would work at its optimum efficiency while delivering maximum power to the load with minimum distortion. Ok, so let's discuss the problems associated with mismatches. When you use a load that is lower than the intended load, the output has to drive the load (speaker) with more current because it is a lower impedance than is expected. Two inherent problems associated with transformers are flux leakage and regulation. Flux leakage is also referred to as leakage inductance. It is related to the current in the secondary, and these problems increase as the current increases. As the current draw in the secondary increases, the primary has a more difficult time transferring the signal to the secondary, so the secondary signal to the load gets squashed, or 'soft-clipped'. This soft clipping is called regulation. While regulation is desireable in a power supply, it is undesireable in a transformer. In other words, in a power supply, if the input voltage or the output load current changes, we don't want the output voltage to change. In a transformer, we want the output voltage to follow the input voltage and not regulate at all. When you put a heavier load on the output than was intended, it will pull the output voltage down, hence regulation. The leakage inductance problem arises because the current from the heavier load causing the regulation to occur reduces the efficiency of the transformer by not allowing the output to follow the input. Transformer designers simulate or view this problem as having extra inductance in series with the primary. The extension of this idea then, is that with the heavier load, you could affect the efficiency of the transformer, alter the frequency response (due to the extra leakage inductance in series with the primary), and cause other distortions to occur. OK, on to mismatching the other way. A speaker is a current operated device in that it responds to the current through it to generate a magnetic field that works against the magnetic field of the speaker magnet to make the cone move in and out. Thinking in very short amounts of time, when the output charges up the voice coil with current, then the signal goes away or gets reduced, the cone system moves the voice coil back to its home or resting position. As it is moving back, it generates a voltage that is fed back up the line into the transformer and appears in the output circuit of the amp. This generated voltage is often referred to as flyback voltage, because we are charging up an inductor, then when we disconnect or stop charging the inductor, the magnetic field in the inductor collapses and induces this big voltage into itself. This big voltage then 'flies back' to the source of the charging current. There is a mathematical formula to determine how big the voltage is and it is related to the inductance of the voice coil, the amount of time it was fed current, and how much current it was charged with. The bottom line is that the voltage fed back to the output circuit is oftentimes much higher than the voltage that was used to drive or charge up the voice coil initially. This voltage gets transformed up by the turns ratio of the output transformer, and in many cases can be over 1,000 volts. What happens then is that arcing can occur between the pins on the output tube socket. Once this has occured, a carbon path forms on the tube socket between the pins. The carbon path allows a steady current to flow between the pins and eventually burns up the socket due to the heat that is generated. For example, it wouldn't be too uncommon to see a transformer turns ratio of 30:1. If we had a voltage fed back from the voice coil that was around 50 volts, 30 times 50 would be a 1,500 volt spike at the plate of the output tube. This is why you often see designers connect diodes in a string between the output tube plates and ground. They are trying to suppress these spikes and dissipate the energy in the diodes rather than allowing an arc to occur at the tube socket. So, when you use a higher impedance load on a lower impedance tap, the turns ratio is higher and resulting fed-back (flyback) voltage gets multiplied up higher than what it would have been with the correct impedance load.
It's just about impossible for me to answer how long an amp would last under these conditions. It all depends on how the designer took these potential problems into account in his or her design with regards to the quality of the tube sockets, the use of stringed diodes, the output circuit operating voltages, etc.
[batty]
Re: teda pochybuju, ze to nekdo bude cist, ale je
From: Graham Kahnt
I need information on how to wire speakers to obtain 2, 4, 8, & 16 Ohm loads.
A schematic for each configuration would be prefered. This has been a puzzle to me for a long time.
Graham, let's look at the definition of impedance first, then go from there. You'll often see a speaker or other device rated at a 'nominal' Z, or impedance. The word 'nominal' comes from the Latin word 'Nomen' which means simply 'name'. An example of where you may have heard this term used in another context is during a space shuttle mission. During the initial ascent, you'll often hear the astronauts say "all systems nominal", or "mission nominal". What they mean is that everything is going as planned, as written, or as described. In the case of a speaker, we are calling, or naming the device a certain impedance. The electrical quantity of impedance is made up of resistance, which doesn't change with frequency, and reactance which does change with frequency. So, impedance is the combination of the two at a particular frequency. Remember in the movie Wizard of Oz when the Scarecrow finally got a brain, he immediately started reciting some bizarre formula about "The sum of the squares of the sides of a right triangle...."? He was reciting the Pythagorean theorm for right triangles. We can use that formula to calculate impedance. Think of a flagpole with the sun casting a shadow on it. The height of the flag pole would represent the reactance, and a line between the base of the flagpole and the point on the ground away from the flagpole where the shadow stops would represent the resistance. If you connected a string between the top of the flagpole and the point on the ground where the shadow stops, the length of the string would be the impedance quantity and would be longer than either of the other two. So, what am I getting at? A speaker that is said to be 'nominally' 8 Ohms will have a resistance lower than 8 Ohms. So, a rule of thumb is that if it measures lower than a commonly used name, such as 8 Ohms, but not lower than the next lower commonly used name, such as 4 Ohm, then you would call it the higher name, or 8 Ohm. Many 'nominal' names have been used over the years, including 2 Ohm, 10 Ohm, and 15 Ohm. 4, 8, and 16 seem to have been standardized though, for the past 30 years or so. The main reason for the variance between several coils, all of which would be called 8 ohms, for instance, would be because each might have a slightly different DC resistance due to the length of the coil, size of the wire used, etc. In each case, though, the DC resistance would be in the range of 5.5 to 6.5 DC Ohms, so it would be called an 8 Ohm device. Another method for naming the impedance of a device is by actually measuring the impedance, or AC resistance of the device with special test equipment. Many have used 400hz as the test frequency, while others have used 1,000hz as the test frequency. Some have derived the name from an impedance plot such as the one shown in Figure 1 below. They declare the nominal impedance to be the impedance at the 'first dip after the first peak'. Notice the large peak at the speaker resonance around 100hz. Then, it drops dramatically, dips, then starts going back up. It would be the impedance at the lowest point of the dip that would be the declared 'nominal' impedance. It's an interesting exercise in using an impedance bridge, but the old rule of thumb we discussed earlier works just fine for declaring a nominal impedance.
Re: teda pochybuju, ze to nekdo bude cist, ale je
From: Graham Kahnt
I need information on how to wire speakers to obtain 2, 4, 8, & 16 Ohm loads.
A schematic for each configuration would be prefered. This has been a puzzle to me for a long time.
Graham, let's look at the definition of impedance first, then go from there. You'll often see a speaker or other device rated at a 'nominal' Z, or impedance. The word 'nominal' comes from the Latin word 'Nomen' which means simply 'name'. An example of where you may have heard this term used in another context is during a space shuttle mission. During the initial ascent, you'll often hear the astronauts say "all systems nominal", or "mission nominal". What they mean is that everything is going as planned, as written, or as described. In the case of a speaker, we are calling, or naming the device a certain impedance. The electrical quantity of impedance is made up of resistance, which doesn't change with frequency, and reactance which does change with frequency. So, impedance is the combination of the two at a particular frequency. Remember in the movie Wizard of Oz when the Scarecrow finally got a brain, he immediately started reciting some bizarre formula about "The sum of the squares of the sides of a right triangle...."? He was reciting the Pythagorean theorm for right triangles. We can use that formula to calculate impedance. Think of a flagpole with the sun casting a shadow on it. The height of the flag pole would represent the reactance, and a line between the base of the flagpole and the point on the ground away from the flagpole where the shadow stops would represent the resistance. If you connected a string between the top of the flagpole and the point on the ground where the shadow stops, the length of the string would be the impedance quantity and would be longer than either of the other two. So, what am I getting at? A speaker that is said to be 'nominally' 8 Ohms will have a resistance lower than 8 Ohms. So, a rule of thumb is that if it measures lower than a commonly used name, such as 8 Ohms, but not lower than the next lower commonly used name, such as 4 Ohm, then you would call it the higher name, or 8 Ohm. Many 'nominal' names have been used over the years, including 2 Ohm, 10 Ohm, and 15 Ohm. 4, 8, and 16 seem to have been standardized though, for the past 30 years or so. The main reason for the variance between several coils, all of which would be called 8 ohms, for instance, would be because each might have a slightly different DC resistance due to the length of the coil, size of the wire used, etc. In each case, though, the DC resistance would be in the range of 5.5 to 6.5 DC Ohms, so it would be called an 8 Ohm device. Another method for naming the impedance of a device is by actually measuring the impedance, or AC resistance of the device with special test equipment. Many have used 400hz as the test frequency, while others have used 1,000hz as the test frequency. Some have derived the name from an impedance plot such as the one shown in Figure 1 below. They declare the nominal impedance to be the impedance at the 'first dip after the first peak'. Notice the large peak at the speaker resonance around 100hz. Then, it drops dramatically, dips, then starts going back up. It would be the impedance at the lowest point of the dip that would be the declared 'nominal' impedance. It's an interesting exercise in using an impedance bridge, but the old rule of thumb we discussed earlier works just fine for declaring a nominal impedance.
[batty]
Re: shrnuti
moc tomu teda nerozumim:)) ale pro me z toho vypliva, ze se nuclear pleta a 4ohmovej reprak je pro 5ohmovej vystup idealni(coz o zapojeni do serie neplati)
Re: shrnuti
moc tomu teda nerozumim:)) ale pro me z toho vypliva, ze se nuclear pleta a 4ohmovej reprak je pro 5ohmovej vystup idealni(coz o zapojeni do serie neplati)
[z28]
Re: batty
ja tomu taky tak moc nerozumim, nicmene sem pochopil, ze terminy jako "vystupni impedance" a "impedance boxu" sou tak trochu alchymie ;o) teda spis orientacni hodnoty, protoze zmerit realnou impedanci v celym kmitoctu je nemozny
v kazdym pripadku zapojit 4 ohmovej repro na 5 ohmovej vystup je naprosto v pohode, to je hluboko pod tolerance mereni v celym kmitoctovym rozsahu. vzpominam si, ze sem v nejakym prospektu od nejakych superhifi masin cet "jmenovita impedance: 16 ohm, realna impedance: 5,5 ohm az 19 ohm"
pruser by byl asi 2 ohm repro na 5 ohm vystup, ale rozdil jednoho ohmu je dle myho zcela nepodstatnej
Re: batty
ja tomu taky tak moc nerozumim, nicmene sem pochopil, ze terminy jako "vystupni impedance" a "impedance boxu" sou tak trochu alchymie ;o) teda spis orientacni hodnoty, protoze zmerit realnou impedanci v celym kmitoctu je nemozny
v kazdym pripadku zapojit 4 ohmovej repro na 5 ohmovej vystup je naprosto v pohode, to je hluboko pod tolerance mereni v celym kmitoctovym rozsahu. vzpominam si, ze sem v nejakym prospektu od nejakych superhifi masin cet "jmenovita impedance: 16 ohm, realna impedance: 5,5 ohm az 19 ohm"
pruser by byl asi 2 ohm repro na 5 ohm vystup, ale rozdil jednoho ohmu je dle myho zcela nepodstatnej
[tandel]
Re:
K výstupu zesiku zapoj basovou bednu a k tomu paralelně přes kondik 8 mikrofaradů tu vejškovou.
Re:
K výstupu zesiku zapoj basovou bednu a k tomu paralelně přes kondik 8 mikrofaradů tu vejškovou.
[dr.fefedebill]
Re:
děkuji,děkuji,děkuji, myslim že volim variantu 4ohmových beden!!!!!!kdebyste k tomu eště někdo něco měli tak piste........
Re:
děkuji,děkuji,děkuji, myslim že volim variantu 4ohmových beden!!!!!!kdebyste k tomu eště někdo něco měli tak piste........