Well it can get the 650 to high volume
Gobsmacked about the Philips Fidelio X1
- Thread starter ThatAsianGuy
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Well it can get the 650 to high volume
Dunno about the 650s but I find it relatively easy to get my 600s loud - but harder to really open up the treble and bass without an amp with good slew/voltage swing. Which IMO is why they have such mixed impression as even some ultra high end amps can have large current delivery capabilities but not so responsive to voltage.
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HD650s and HD600s need a good healthy voltage swing for optimum performance (not just loud) while AKG 7xx series need plenty of current
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HD600s and HD650s have a very high number of turns of extremely thin wire in their voice coils, which results in a relatively high impedance of 300 ohms (nominal) but this increases to over 500 ohms around 100Hz. Overcoming this resistance to get the diaphragms moving back and forth requires a very healthy +/- voltage swing, more than you tend to get from USB powered amps. Even though the voltage may be high, they don't require a lot of power due to their high efficiency.
AKG 7xx series use far fewer turns of thicker wire in the voice coils which gives them a low impedance, so less voltage is required but they are also extremely inefficient, so they need a lot of power to drive them and that has to come from using more current.
This is why OTL valve amps like the Valhalla and the Bottlehead Crack are so good with the HD650/600, they have relatively high impedance outputs, which isn't an issue with the high impedance headphones and provide huge voltage swings to get those diaphragms vibrating happily. On the flip side though, OTL valve amps tend to be poor when using low impedance, inefficient headphones such as the AKGs or planar magnetics because they can't provide enough current.
AKG 7xx series use far fewer turns of thicker wire in the voice coils which gives them a low impedance, so less voltage is required but they are also extremely inefficient, so they need a lot of power to drive them and that has to come from using more current.
This is why OTL valve amps like the Valhalla and the Bottlehead Crack are so good with the HD650/600, they have relatively high impedance outputs, which isn't an issue with the high impedance headphones and provide huge voltage swings to get those diaphragms vibrating happily. On the flip side though, OTL valve amps tend to be poor when using low impedance, inefficient headphones such as the AKGs or planar magnetics because they can't provide enough current.
As an aside it is possible to get enough voltage swing from USB amps but potentially requires DC-DC conversion and the filtering to make that acceptable - which tends to be power inefficient, take up a fair bit of space and produce moderate amounts of heat - which doesn't tend to be ideal for the form factor typical of a USB amp. I don't know personally which ones are and aren't capable of enough voltage swing.
Supposedly the minimum voltage swing to fully drive the 600 series is pretty much bang on the max a USB source (without boosting) can supply so assuming good enough slew rates, etc. an efficient design can probably do it without resorting to crude boosting mechanisms - even a relatively small drop in output though would drop below ideal.
Supposedly the minimum voltage swing to fully drive the 600 series is pretty much bang on the max a USB source (without boosting) can supply so assuming good enough slew rates, etc. an efficient design can probably do it without resorting to crude boosting mechanisms - even a relatively small drop in output though would drop below ideal.
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Not without serious modification going by the write ups - seems to use the NJM4556 which I don't rate with the 600 series personally but other people might have a different opinion, has cheap input capacitors that could cause a problem with dc offset and horrid hack with the output to balance the input bias - which wouldn't matter with the 600 series but would compromise its performance with low impedance headphones.
It looks like a glorified cmoy with flawed but not seriously broken implementation.
It looks like a glorified cmoy with flawed but not seriously broken implementation.
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Soldato
Thanks
I have M1MKII for travel and now X2 for the office. Would like to try an AMP and/or DAC. Any recommendations? Willing to spend 100-200'ish if the result justifies it.
Years ago I had the Fiio E5 which I believe is similar output to the E6. I managed to get a lot of headphones up to ear piercing volumes but the resolution took a hit - was no fullness, no depth and made everything sound harsh.
Fiio amps are amazing for the price but they are not the most capable in terms of reaching potential. Take you HD650 to a hifi store and ask them to set up some sources for you and you will see what these things are capable of.
The 650 scale like crazy and while they sound good out of most things, they really do range from mid ranged to hifi depending on source. The X1 and X2 are great for just plugging in and play but when I compare them to higher end headphones they just lack in a lot of areas, I'm confident that the 650's will leave them for dead when you try them on other gear, if they don't, I'll throw my PS4 in the Thames.
I generally avoid getting in to science talk but this is a very good piece of information. It's also a big reason why you will hear people mention the the 650 sound better with tubes..it isn't always true but a big reason is this above.
I know mate I am saving for an amp even on the e6 I can hear they are far more refined than the fidelio
I don't want a tube amp though cant be doing with tubes breaking and replacements especially the schiit stuff where you have to send it back to them when the tube goes
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Send it back? Only the original Vali had built in tubes which mean you have to send them back. With tube amps you just buy new tubes and slot them in then done. I've got about 30 pairs of tubes here, some are many years old and have 1000's of hours on them, I've never had one gone wrong. They last ages and in 5-10 years time when they die, £30-40 for a new set and you are good to go.
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What are you comparing them to. I find that they have bass by the bucketload, this is of course unless you are comparing them to certain fashion headphones.
What are you plugging them into?
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Hey guys im after soem advice please. after soem advice i upgraded my soundcard to a Asus Xonar Essence STX II 7.1(i got the 7.1 vers for a lower price than the standard on ocuk) anyhow putting my soundcard into headphone mode what is the correct setting i should be using for my x1s ? as in the gain pls.
thank you
thank you
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32~64 ohm