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Post by ale on Sept 21, 2017 17:08:07 GMT -5
Hi everyone, I really don't understand the headphone amp specs. For my TA-100 I see this:
Analog Performance (headphone output power)
8 Ohms: 23 mW / channel
33 Ohms: 90 mW / channel
47 Ohms: 127 mW / channel
150 Ohms: 145 mW / channel
300 Ohms: 114 mW / channel
600 Ohms: 75 mW / channel
I was thinking in Beyerdynamic DT770 or DT990 250ohms versions (I can get them semi cheap here in Perú)
Is the headphone amp powerful enough to drive those?
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Post by garbulky on Sept 21, 2017 21:12:52 GMT -5
Well the aswer to that is .....it's going to sound okay but it won't do the headphones justice. If you want the full potential of your DT 770 buy the Mini-x a-100 (which has a headphone jack). Also I would reccomend the DT 880 if you have a chance . If you don't want to buy the A100 then you should go with the 25 ohm or 80 ohm version of either unit. The 250 ohm means you need a beefy headphone amp (of which the a-100 is definitely one). The 880 is compared to the sennheiser HD600 and with the A-100 the HD600 it goes head to head with my much more expensive speaker setup (we are talking about $4500). Without it's simply a good headphone setup but not anywhere close to my speakers in quality. If you are considering headphones, I would definitely buy the A-100 to use as a headphone amp over the CD-100. No hesitation
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Post by ale on Sept 22, 2017 9:40:06 GMT -5
Thanks! Unfortunately, my budget has been maxed out.. I started thinking about replacing the main speakers.. which I did, followed by replacing the recevier...,and afterwards I bought a nice sub, so the headphone now is left with a smaller budget. If the 250ohms are not that suitable for the TA-100 heaphone amp, I will have to look to other options, since I can't find here (Peru) the 32 o 80ohms version. I'm looking right now at Meze's 99 Neo , seem to be nice and at 32ohms will match almost any amp.
Thanks again for your response!
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Post by mshump on Sept 22, 2017 10:03:01 GMT -5
You shouldn't have any problems driving those headphones with the TA-100, unless you want to drive them until your ears bleed. The specs for the 770 headphones says Power handling capacity . . . . . . . . . . . . 100 mW The TA-100 specs show :150 Ohms: 145 mW / channel,300 Ohms: 114 mW / channel.
At 250 Ohms you will be between 114 and 145 mw.
Mark
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Deleted
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Post by Deleted on Sept 22, 2017 11:45:38 GMT -5
The TA-100 is more than capable of driving the DT-770 250 Ohm version, because I have a pair of the Premium edition (2005) and they run quite well on the one we have here.
I also have the DT-880, and I can confirm they are also a wonderful-sounding headphone in the vein of the DT-770 and even a little nicer in some ways. They are also driven very well by the TA-100, although I use the A-100 at my desk to drive them most of the time. They are an especially good match for the A-100 with the dropping resistors in-line because of their flat impedance profile. Incidentally the A-100 drives the DT-770s very nicely too.
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Post by garbulky on Sept 22, 2017 11:50:51 GMT -5
They are an especially good match for the A-100 with the dropping resistors in-line because of their flat impedance profile. Incidentally the A-100 drives the DT-770s very nicely too. I was curious what's the relationship with the resistors and the flatness of the impedance?
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Post by pallpoul on Sept 22, 2017 13:18:45 GMT -5
The A-100, WITH THE JUMPERS PLACED ON, is capable of driving any headphone, regardless of their impedance and regardless of their of power requirement with authority, PERIOD. it will be the last headphone amp you will ever buy, Period.
All u need with it I a good DAC. a DC-1 is a perfect match. I use both, just be careful not to ruin your headphones as Emotiva stated on the manual of the A-100 (page 11) it won't be liable if you fry your headphones while using A-100 in this manner.
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Deleted
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Post by Deleted on Sept 22, 2017 13:23:19 GMT -5
They are an especially good match for the A-100 with the dropping resistors in-line because of their flat impedance profile. Incidentally the A-100 drives the DT-770s very nicely too. I was curious what's the relationship with the resistors and the flatness of the impedance? You can look up online the effects of driving a reactive load from an amplifier with high output impedance. The resistors in-line are there to reduce level and prevent people from blowing up headphones or their ears, and to maximize the usable range of the volume knob, but if the load is reactive, with large impedance peaks/swings, there can be some impact (minor, less than a couple dB but "it depends") on the frequency response and bass damping of the headphone, usually between 100 and 300 Hz. Naturally, headphones with flatter impedance profiles experience less of this, and that tends to be the sign of a well-designed headphone. (The Beyers are an example of this.) This is the reason for some of the airflow-resistive gauze and stuffing materials used in headphones, to provide resistive ("aperiodic") damping of the mechanical system to minimize the mechanical reactance and thus the reflected electrical reactance of the load presented to the amp. Bypassing the dropping resistors in the A-100 (using the included jumpers) eliminates the impedance-variant behavior entirely because the amp itself has very low output impedance. In that case you just need to use headphones with a high impedance or low sensitivity, or live with the reduced 'usable' range on the volume knob. The method of using dropping resistors and powering the outputs directly from amplifier outputs has been used for decades on "vintage" equipment, and in the case of the A-100 the benefit is that the amplifier really sounds wonderful driving your headphones, even very difficult ones to drive.
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Post by garbulky on Sept 22, 2017 14:26:48 GMT -5
I was curious what's the relationship with the resistors and the flatness of the impedance? You can look up online the effects of driving a reactive load from an amplifier with high output impedance. The resistors in-line are there to reduce level and prevent people from blowing up headphones or their ears, and to maximize the usable range of the volume knob, but if the load is reactive, with large impedance peaks/swings, there can be some impact (minor, less than a couple dB but "it depends") on the frequency response and bass damping of the headphone, usually between 100 and 300 Hz. Naturally, headphones with flatter impedance profiles experience less of this, and that tends to be the sign of a well-designed headphone. (The Beyers are an example of this.) This is the reason for some of the airflow-resistive gauze and stuffing materials used in headphones, to provide resistive ("aperiodic") damping of the mechanical system to minimize the mechanical reactance and thus the reflected electrical reactance of the load presented to the amp. Bypassing the dropping resistors in the A-100 (using the included jumpers) eliminates the impedance-variant behavior entirely because the amp itself has very low output impedance. In that case you just need to use headphones with a high impedance or low sensitivity, or live with the reduced 'usable' range on the volume knob. The method of using dropping resistors and powering the outputs directly from amplifier outputs has been used for decades on "vintage" equipment, and in the case of the A-100 the benefit is that the amplifier really sounds wonderful driving your headphones, even very difficult ones to drive. I don't know if you had a hand in designing the A-100. I just want to let you know that you aren't joking about the amp sounding wonderful. There's really no such thing as overstatement with this amp. it is a BEAST in detail, power, control, dynamics, bass, you name it. Just a real delight. I have a hard time imagining that there is any other amp less than a $1000 that can compare with its superb performance. I hope you will consider a balanced version of this for headphone only use or even stackable headphone monoblocks with a bit of additional class A. Y'all would dominate the headphone market niche with such a product. $500 for stackable monoblocks with insane power? Get outta here! So what you are saying is that the resistors affect output impedance of the amp. Do you have any data on the output impedance with the resistors engaged? What you said about tone makes sense because I did notice a slight tone difference with and without the resistors. With the resistors in the path, the sound is slightly warmer in the bass and lower mids region. I prefer this tone signature. But I definitely prefer it without the resistors due to the insane transient response! I guess the tone thing also makes sense with inline attenuators used on the outputs of preamp? When I used them (on the XDA-1) I also noticed a tonal change in the low mids/upper bass. I was told there is no tonal change because it's just a resistor. But that didn't match my experience with it.
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Post by ale on Sept 22, 2017 16:55:37 GMT -5
The TA-100 is more than capable of driving the DT-770 250 Ohm version, because I have a pair of the Premium edition (2005) and they run quite well on the one we have here. I also have the DT-880, and I can confirm they are also a wonderful-sounding headphone in the vein of the DT-770 and even a little nicer in some ways. They are also driven very well by the TA-100, although I use the A-100 at my desk to drive them most of the time. They are an especially good match for the A-100 with the dropping resistors in-line because of their flat impedance profile. Incidentally the A-100 drives the DT-770s very nicely too. Great! I don't think I will be able to audition.. do you have any feedback regarding the DT770 , DT990 and Meze 99 Neo? I can find them for roughly the same budget here.. I listen lots of different music, from classical, to Rock, techno, etc.. I do like bass.. my current headphones are IE Sennheissers momentum IE2 and I quite like those although.. I would like something much better of course!
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Post by ale on Sept 25, 2017 11:21:54 GMT -5
You shouldn't have any problems driving those headphones with the TA-100, unless you want to drive them until your ears bleed. The specs for the 770 headphones says Power handling capacity . . . . . . . . . . . . 100 mW The TA-100 specs show :150 Ohms: 145 mW / channel,300 Ohms: 114 mW / channel. At 250 Ohms you will be between 114 and 145 mw. Mark Mark, thanks for your response, .. but left me with a question... 114 to 145 mw..is that.. like "a lot" I don't expect to listen at insane levels, I try to keep my ears healthy.. but I do like some volume! thanks!!!
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Post by mshump on Sept 25, 2017 11:34:13 GMT -5
You shouldn't have any problems driving those headphones with the TA-100, unless you want to drive them until your ears bleed. The specs for the 770 headphones says Power handling capacity . . . . . . . . . . . . 100 mW The TA-100 specs show :150 Ohms: 145 mW / channel,300 Ohms: 114 mW / channel. At 250 Ohms you will be between 114 and 145 mw. Mark Mark, thanks for your response, .. but left me with a question... 114 to 145 mw..is that.. like "a lot" I don't expect to listen at insane levels, I try to keep my ears healthy.. but I do like some volume! thanks!!! That;'s hard to say. Headphones are just mini speakers (for lack of better words). So just like normal home speakers, you don't want to under power them, but at the same time if you overpower them with too many watts you can damage them also. you want enough power to handle the dynamics of the music. being in the band of 114-145mw will be fine. There are headphones out there that require more and also some that need much less. Mark
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KeithL
Administrator
Posts: 9,901
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Post by KeithL on Sept 25, 2017 14:53:15 GMT -5
When the resistor is bypassed, the output impedance of the A-100 is effectively zero (it's about 1/50 Ohm). Because this is far lower than the impedance of your headphones, there is very little interaction between them. (So the amplifier will deliver the signal to the headphones exactly as it is, and the headphones will play it as they are designed to.) The resistors are 220 Ohms; so, when they're placed in series with the output impedance of the amp itself, the output impedance of the amplifier becomes 220 Ohms. Because this 220 Ohm output impedance is of the same order of magnitude as the impedance of headphones, the two may now interact significantly. It is important to note that, by adding the resistor, we have created conditions where the amp is "willing" to interact with the impedance of your particular headphones. How much interaction actually occurs, and what character it assumes, will depend on the specific characteristics of the model and brand of headphones you have. (Your headphones sound slightly warmer in the bass and lower midrange; with other headphones, the effect may be quite different, as well as being more or less noticeable.) Your experience with the XDA-1 is actually rather unusual. Typical headphones have an "interesting" impedance which consists of the inductance of their voice coil, the mechanical resonance of their moving parts, and various mechanical characteristics that equate to electrical inductance, capacitance, and resistance. The variations in sound are a result, not of the resistor itself, but of how the resistor interacts with these complex impedance characteristics. If you were to connect that output, through the resistor, to a purely resistive load, there should be no audible interaction. In theory, because the input impedance of a preamp is typically almost a pure resistance, and attenuators are also supposed to be pure resistors, this should be the case when connecting your XDA-1 to the input of a preamp. (In practice, nothing is absolute or perfect, and even interconnects have capacitance and inductance, which probably accounts for the differenc eyou're hearing.) You can look up online the effects of driving a reactive load from an amplifier with high output impedance. The resistors in-line are there to reduce level and prevent people from blowing up headphones or their ears, and to maximize the usable range of the volume knob, but if the load is reactive, with large impedance peaks/swings, there can be some impact (minor, less than a couple dB but "it depends") on the frequency response and bass damping of the headphone, usually between 100 and 300 Hz. Naturally, headphones with flatter impedance profiles experience less of this, and that tends to be the sign of a well-designed headphone. (The Beyers are an example of this.) This is the reason for some of the airflow-resistive gauze and stuffing materials used in headphones, to provide resistive ("aperiodic") damping of the mechanical system to minimize the mechanical reactance and thus the reflected electrical reactance of the load presented to the amp. Bypassing the dropping resistors in the A-100 (using the included jumpers) eliminates the impedance-variant behavior entirely because the amp itself has very low output impedance. In that case you just need to use headphones with a high impedance or low sensitivity, or live with the reduced 'usable' range on the volume knob. The method of using dropping resistors and powering the outputs directly from amplifier outputs has been used for decades on "vintage" equipment, and in the case of the A-100 the benefit is that the amplifier really sounds wonderful driving your headphones, even very difficult ones to drive. I don't know if you had a hand in designing the A-100. I just want to let you know that you aren't joking about the amp sounding wonderful. There's really no such thing as overstatement with this amp. it is a BEAST in detail, power, control, dynamics, bass, you name it. Just a real delight. I have a hard time imagining that there is any other amp less than a $1000 that can compare with its superb performance. I hope you will consider a balanced version of this for headphone only use or even stackable headphone monoblocks with a bit of additional class A. Y'all would dominate the headphone market niche with such a product. $500 for stackable monoblocks with insane power? Get outta here! So what you are saying is that the resistors affect output impedance of the amp. Do you have any data on the output impedance with the resistors engaged? What you said about tone makes sense because I did notice a slight tone difference with and without the resistors. With the resistors in the path, the sound is slightly warmer in the bass and lower mids region. I prefer this tone signature. But I definitely prefer it without the resistors due to the insane transient response! I guess the tone thing also makes sense with inline attenuators used on the outputs of preamp? When I used them (on the XDA-1) I also noticed a tonal change in the low mids/upper bass. I was told there is no tonal change because it's just a resistor. But that didn't match my experience with it.
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Post by garbulky on Sept 25, 2017 15:12:05 GMT -5
When the resistor is bypassed, the output impedance of the A-100 is effectively zero (it's about 1/50 Ohm). Because this is far lower than the impedance of your headphones, there is very little interaction between them. (So the amplifier will deliver the signal to the headphones exactly as it is, and the headphones will play it as they are designed to.) The resistors are 220 Ohms; so, when they're placed in series with the output impedance of the amp itself, the output impedance of the amplifier becomes 220 Ohms. Because this 220 Ohm output impedance is of the same order of magnitude as the impedance of headphones, the two may now interact significantly. It is important to note that, by adding the resistor, we have created conditions where the amp is "willing" to interact with the impedance of your particular headphones. How much interaction actually occurs, and what character it assumes, will depend on the specific characteristics of the model and brand of headphones you have. (Your headphones sound slightly warmer in the bass and lower midrange; with other headphones, the effect may be quite different, as well as being more or less noticeable.) Your experience with the XDA-1 is actually rather unusual. Typical headphones have an "interesting" impedance which consists of the inductance of their voice coil, the mechanical resonance of their moving parts, and various mechanical characteristics that equate to electrical inductance, capacitance, and resistance. The variations in sound are a result, not of the resistor itself, but of how the resistor interacts with these complex impedance characteristics. If you were to connect that output, through the resistor, to a purely resistive load, there should be no audible interaction. In theory, because the input impedance of a preamp is typically almost a pure resistance, and attenuators are also supposed to be pure resistors, this should be the case when connecting your XDA-1 to the input of a preamp. (In practice, nothing is absolute or perfect, and even interconnects have capacitance and inductance, which probably accounts for the differenc eyou're hearing.) I don't know if you had a hand in designing the A-100. I just want to let you know that you aren't joking about the amp sounding wonderful. There's really no such thing as overstatement with this amp. it is a BEAST in detail, power, control, dynamics, bass, you name it. Just a real delight. I have a hard time imagining that there is any other amp less than a $1000 that can compare with its superb performance. I hope you will consider a balanced version of this for headphone only use or even stackable headphone monoblocks with a bit of additional class A. Y'all would dominate the headphone market niche with such a product. $500 for stackable monoblocks with insane power? Get outta here! So what you are saying is that the resistors affect output impedance of the amp. Do you have any data on the output impedance with the resistors engaged? What you said about tone makes sense because I did notice a slight tone difference with and without the resistors. With the resistors in the path, the sound is slightly warmer in the bass and lower mids region. I prefer this tone signature. But I definitely prefer it without the resistors due to the insane transient response! I guess the tone thing also makes sense with inline attenuators used on the outputs of preamp? When I used them (on the XDA-1) I also noticed a tonal change in the low mids/upper bass. I was told there is no tonal change because it's just a resistor. But that didn't match my experience with it. This is great data Keith. Thank you.
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Post by ale on Sept 25, 2017 16:30:06 GMT -5
Mark, thanks for your response, .. but left me with a question... 114 to 145 mw..is that.. like "a lot" I don't expect to listen at insane levels, I try to keep my ears healthy.. but I do like some volume! thanks!!! That;'s hard to say. Headphones are just mini speakers (for lack of better words). So just like normal home speakers, you don't want to under power them, but at the same time if you overpower them with too many watts you can damage them also. you want enough power to handle the dynamics of the music. being in the band of 114-145mw will be fine. There are headphones out there that require more and also some that need much less. Mark Yeah... but maybe there was a way to "predict" performance. Like in normal speakers, I check the sensitivity, and can sort of know the volume I will get with certain amplifier, it's not perfect.. but quite good way. With headphones, things seem to be more esoteric.. don't understand why.. thanks anyway! I will try them out, hopefully it's ok.
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