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View Full Version : Anyone finished burning in their TC-7520 yet?



StanleyB
27-02-2009, 16:32
Anything to report that might be of interest?

I had one customer pass by with his K701 headphones. He said he never heard them sound so loud and with so much detail in the bass. But I knew that already. I got a set of K701 myself:).

Stan

Clive
27-02-2009, 17:27
Anything to report that might be of interest?

I had one customer pass by with his K701 headphones. He said he never heard them sound so loud and with so much detail in the bass. But I knew that already. I got a set of K701 myself:).

Stan
Mine's been running about 20 hours so far. I had a listen last night when it had around 10 hours. Running from PC and a Meridian 588 (as a transport) it was definitely an improvement on the DAC in the Meridian 588 - this is a £2k player from just a few years ago. Two areas stood out for me:
- Bass, deep, tight and detailed
- Soundstage between the speakers - there's much more of it.

Overall it sounds more like playing records than CD. I'll listen some more over the weekend.

tizer2000uk
27-02-2009, 22:03
Got mine this morning and these are my thoughts thus far:

Compared to the 7510 6/4 I purchased about a month ago, the sound has far more 'meat', a much tighter bottom end and more detail coming through, one tune in particular has a very discrete backing chorus line in the mix that on lesser systems makes it hard to concentrate on, with the 7520 and SR80's I found myself being able to 'look' at the chorus line in more detail than I have been able to previously, so much more in fact that I found myself hearing the main chorus as the backing track if that makes any sense. The 7510 has a slightly thinner sound in direct comparisons I have performed this evening, each instrument on the 7520 has more body and space, a fancy way of saying it conveys more information if you like.

The 7510 definately still has a place in the market tho, in fact if I already had the 7520 and needed an additional unit the 7510 would still be it, on a main system where the primary listening source will be loudspeakers it is still an excellent unit at a very low price, the 7520 has a USB port and a very good headphone section which suits my requirement perfectly while I am in my office.

The sound I am sure will mature a little more which is no bad thing. I also had some guys in the office where I work have a little listen, all agreed the sound was amazing, all of them were grinning ear to ear and tapping their feet along to Dire Straits and Eric Clapton and none of them wanted to give it back. All of them thought the 7520 cost me at least £400 on the strength of the sound and all were very surprised at how little it cost.

A while back I spent a lot of time looking into headphones for gaming on my pc, after hearing the GS1000's in action I figured that a good set of cans paired with good sound processing would give my ears the right amount of detail required to create a believable soundstage in game.

After listening to and dismissing lots of cans aimed at gamers with 5.1 and an array of other crap (If its aimed at gamers it is probably useless) I settled for the Grado's (SR80's) as they are sooooo revealing. My only source of amplification at this point was the headphone socket on the control pod of my Logitech Z-5500's and they did not sound anywhere near as good as they did on the amp in store so I had made my mind up at this stage that an amp would have to be purchased, the only problem was that I did not require all the functionality or size of an amp in my office so started Googling headphone amps which led me to the 7510, after setting it up I was immediately impressed at how much the sound had improved, definately night and day over both the headphone out on the X-FI card and the Z-5500's but also over the 7 year old DV717 player in my lounge. Playing Left4Dead through this combo had people calling me a cheat as I was shooting the enemy through walls based purely on what I could hear. Trying the same today with the 7520 was even more impressive, on busy sections of the game I can hear far more than I could previously which is fantastic.

I can also confirm that through the USB port the 7520 is recognised as a seperate sound card and can not utilise the processing of game/movie audio from any other sound card you have in your system, the Kernel Sound plugin for Foobar has also refused to output sound through the USB and so the digital ouput on your pc will have to be used if you are particular about the route your audio takes, I personally have not heard any difference in the sound from the USB compared to the Coax but I'm sure some might.

Another thing that impressed me was the fact the opamps are not soldered in place on the headphone section and can be upgraded if you so wish to go down this route, its not something I will do for a while as I am very happy with the sound as is. A number of electronics engineers where I work (Aerospace company) also commented on its well designed circuitry and upgrade options and the fact the headphone section looks as if it can be lifted out seperately for those who want to get your soldering irons out and upgrade caps etc.

As you have probably guessed I am very happy thus far!

Tyrone

Peter Stockwell
28-02-2009, 04:18
Tyrone,

Brilliant review! I'm an old fart and it has never once occured to me that high quality sound would be of the slightest interest to gamers. A revelation.

sponge
28-02-2009, 16:52
As a bit of sceptic when it come to long burning-in periods for electronic equipment, I have to admit that I may have to reconsider my thinking.

When I received my 7520 on Wednesday (the 25th) I connected up with my K701's in the headphone socket and thought "Hmmm, well - There's scope for improvement". The sound to me was very thin - Bright even - And where's the bass?
However, I had read about the quite extended burning-in some members had said was necessary, so I stuck the Ultrasone Test CD in the portable CDP - Optical out into the DAC, selected repeat and left it to simmer.

Here we are now with about 60 hours on the clock and I have just had a listen. Well! Bass is back, there's detail in spades and the huge K701 soundstage is, if anything even wider. I'm grinning as I listen as I feel the DAC has even more to give. I'll hold back on any critical listening and comparison to my normal headphone amp until we have 100+ hours.

I'm going to enjoy the 7520 I know it - So to any new owners or potential owners: Just be patient and get some burn-in hours logged, it's well worth the wait.

Ken

sanchezxxx
28-02-2009, 17:05
Hi All,

It was me that popped round to test the new DAC with my AKG 701. I was suitably impressed to walk away with the DAC but mine has only had a couple of hours burn in. Will post a proper review later in the week once I have been able to spend some proper time with the unit. I will say now that the amp in this can drive the AKG's loud without any issue.

tizer2000uk
28-02-2009, 18:46
Well I used to be a bit of a sceptic until some engineers where I work mentioned that for the most part this is true for all components that don't undergo any chemical process, capacitors obviously do and so benefit from running in. The 7520 has 'settled down' much more now in the last 30 hours...

sponge
28-02-2009, 19:32
I remain sceptical as I'm not sure what is happening during the burning-in process. I understand that capacitors require a forming time - But 100 hours? - I think not. Perhaps it's just an audio thing. Whatever, I'll just reap the benefits and enjoy my music that much more.

Ken

Dougr33
28-02-2009, 19:32
I'm surprised I've never read of 'testing' on this burn-in issue, which I agree usually seems quite true (just as solid state equipment, like me loved NAD, sound better warm).

Wouldn't it be easy?
>gather several audiophiles with tested good hearing
>buy two identical DACs (let's say), play them each for 10 minutes, have the group declare them to sound 'the same'.
>burn in one for 200 hours, bring the group back, and they ought to be able to pick it out using same equipment as before.

sponge
28-02-2009, 19:46
Dougr33,
I think a can of worms would be opened up - Let's suppose the audiophiles failed to pick out the "burned-in" DAC - Wouldn't they just say that the sample size was too small and insist the test was repeated with (say) 20 DAC's? Where would it end...
Then again, perhaps they fear they could not tell any difference...

Ken

tizer2000uk
01-03-2009, 02:02
I must admit I remain slightly sceptical myself, I'm a man of logical thinking and the burning in process does not make an awful lot of sense to me. Maybe alot of it has to do with one's hearing becoming more accustomed to the sound over time?

I would also be interested to know if anyone here has ever had two units side by side and heard a noticeable difference.

I had quite an interesting chat with one of the guys at work who has been designing electronic wizardry for space and defence companies for many years and who also has designed alot of his own audio kit for home and he remains very skeptical about such things as very expensive cabling, the burning in process, isolation platforms for amplifiers and valve amps.

He mentioned building an amplifier which essentially delivered every last ounce of information from an audio track, something he tested by hearing a recording made and then having it played back on his amp.

For him the music sounded exactly the same as it did when recorded in the studio, others however thought the sound was too 'clinical', especially when playing back modern mainstream cd's, on valve amps however people though the sound was 'warmer'.

He basicly said that valve amps colour the sound and tell some white lies to make recordings, especially bad ones sound more appealing, aparently being able to hear the pedals on a piano within the mix is not everyones cup of tea.

His views on why manufacturers charge megabucks for electronic gadgetry cannot however be printed in such polite company.

Photochromatic
02-03-2009, 09:33
Crossposted by request from http://theartofsound.net/forum/showthread.php?p=35619#post35619
================================================== ===============

So here is another review - somebody please check the nightly backups are working, I'm not going to do this again!:doh:

I received my TC-7520 the week before last, two days after it shipped, and about a week before I was expecting it. Good start!

First Impressions
The unit looks good in spite of lacking some of the flashy accoutrements of some of its competition. It feels solid, the finish is clean, the detail on the front has a minimalist, quality feel, and I like blue LEDs! Around back, the connectors are clearly labelled and the screws underneath all sit nicely. You get the feeling that you could happily drop this down the stairs and it would still work. I won't :)
The volume knob moves smoothly, with perhaps a little less resistance than I would like, but it does have a quality feel to the motion.
I don't like the wall-wart PSU but I won't complain at this price! At least it is small.

Setup
I listen mainly with headphones, so the headphone amp stage is of as much interest to me as the DAC itself.
The TC-7520 is connected via TOSLINK to a Mac Pro, set to 44k1, 24-bit output. I play mainly ALAC (lossless) files from iTunes, although there are some mp3 and AAC in there too, as well as a few higher resolution 96k-24bit WAV files. All of the ALAC is ripped by yours truly using MAX to get bit-perfect transfers. I'm mainly listening on Audio-Technica ATH-M50 headphones, which are very revealing and detailed (sometimes to a fault). I have others I sometimes use to see if what I am hearing is cans-related, but I know the M-50s really well.

Burn-In
My TC-7520 has about 200 hours of use on the clock now, and I think it has settled down quite a lot.
The DAC burned in over about 50 hours. Initially there was a sibilant character to the high's and an almost hyper-detailed character to the sound in general, but it has settled down and opened out to become much more musical than my initial impression of it.
The head amp is *mostly* burned in now. It managed to be both tight up high and sloppy down low to start with. The tightness at the high end was quite quick to disappear (30-40 hours) and the bass has firmed up a lot, and is still improving. It is still challenged a little by some of my most difficult tracks that are very bassy and busy, especially if there is a lot of gain in the recording. However the improvement so far has been substantial *and* is continuing *and* I am nit-picking over some dozen particularly challenging tracks. Give it another 100 hours, and I am sure it will be fine.

Warmup
I find that the amp in particular needs about 30 minutes from cold to sound at its best. I rarely turn stuff off anyway.

Impressions
The first thing I notice when listening via the 7520 is actually the spaciousness of the sound stage, even when listening with closed headphones. I can place individual violins of the LSO when listening to Elgar. I could almost reach out and smack the guy with the cough in the bar where Miles Davis is playing. The imaging is very precise, and live music in particular just, well, comes to life.
The detail and clarity are also excellent. Fret movements, picks, snares, spit(!) - its all there. I like to hear detail in my music, even to a fault. I am loving the detail that the 7520 reveals, especially in live and/or largely acoustic music. Some of my stuff is originally ripped from vinyl and even in that I am hearing detail that I had forgotten (or never knew) was there.
Vocals are lovely - especially female vocals (although that may just be my preference anyway). I'm finding it hard to multi-task when listening via the TC-7520 because I keep having to stop and listen!
When playing "loud" music, I am impressed by the ability of the 7520 to clearly show detail in the midst of distortion (note comments about the amp and busy bass though).
Overall, the character of the DAC + Head Amp is slightly warm (but without adding colour), not at all clinical, and remarkably versatile. I can go from Punk to Jazz to Metal to Classical without noticing any real shortcomings.
I should also mention the noise floor of the amp - there isn't one! Turned up all the way, I can't hear any hiss at all through 38-ohm headphones. None at all. Nice.

USB
I have A/B'd the USB and the TOSLINK connectors and can't discern any difference at all. That's a good USB stage!

Low Bit-rate Files
As I have posted earlier, the TC-7520 seems to do something to enhance the sound (or at least mask the errors) in low bit-rate files. It is almost like some kind of up-sampling is at work (although I doubt it, given Stan's opinion of up-sampling). 64 and 128-bit .mp3 files don't sound like lossless by any means, but they don't offend as much as normal. Almost as though something has smoothed out the spiky bits of the waveform where the errors are, and left the rest alone. It is not that they sound better, as much as that they don't sound as bad! Given the detail that the 7520 otherwise imparts, I would expect it to emphasise the difference between the LQ and HQ files, and it does, just not offensively.

My Verdict
I paid USD200 for this device. I am very happy.
I think the DAC is excellent value for money. I'm not an expert on high-end DACs, but I have heard a few, and to my mind the TC-7520 is proof of the law of diminishing returns. I think you'd need to spend a pile of money on the rest of your rig before you needed something better then this.
If you are going to use headphones a lot, then the news is even better. This isn't the very best head amp I have heard, but it is at least 80% of amps which cost five times the money of the 7520, and then you'd still need a DAC.

StanleyB
09-03-2009, 17:52
The new external PSU has been cleared and received all the relevant approvals for use on mains anywhere in the world:). A spy pic of it without a figure of 8 lead attached:
http://beresford.me/images/TC-7520/TC-7520PSY.jpg

And a spy pic of the final production version of the power cap that is the key to the Virtual DC power supply inside the TC-7520. Its a beefed up version of the PSU in the TC-7510. Instantaneous current dumping ability is reckoned to be around 6Amps.
http://beresford.me/images/TC-7520/PC1.jpg

Spectral Morn
09-03-2009, 18:04
Very interesting Stan... This should help sound out quite a lot or at least that is what happens with psu upgrades on other products.


Regards D S D L---Neil :)

Covenant
09-03-2009, 18:06
Right Stanley a few questions if you dont mind....
Firstly, I think you said its a switched mode power supply-any reason why you havent gone down the linear route as this is supposed to give a cleaner supply?
Secondly, the power cap-I must have missed this one. Is it already in the 7520 or is it going to be a mod?
All good stuff though.

StanleyB
09-03-2009, 18:42
1. That particular switched mode PSU has been designed for ultra low noise and heat dissipation. It's main purpose is to top up the power cap, rather than drive the DAC electronic circuits. It's running at a modest 1.2A. The 'current dumping' is done by the power cap. The latter feeds parallel wired power supply rails that use separately regulated 5V for the digital section and 10V for the analogue feed. Each regulator is on its own PCB section as well in order to cut down on any noise bleeding between the digital and analogue section.

2. The power cap is already fitted to the existing TC-7520. But the printed top cap was not yet ready. As you can imagine, getting your own caps made ain't for the faint hearted.

Stan

leo
09-03-2009, 19:11
A SMPS goes nicely with these new green regulations;)

Correct me if I'm wrong Stan but I'd imagine supplying the dac with a linear supply would add a huge increase in price? its also hard getting the things to comply with the regs today unfortunately, its something which is causing a lot of companys some grief.
It seems like Stans done the clever thing and optimized the dac to be used with a smps, I can say this is no straightforward thing, wise choice on the big input cap too:smoking:

A SMPS usually has a much stiffer supply than an average sized linear, its physically much smaller and lighter, input AC voltage is also less hassle than linears
Supplying these with a commercial unit like a dac makes total sense IMO

Covenant
09-03-2009, 19:26
I am sure you are right Leo but when I looked into this for my SB3 everyone said linear was the way to go and I coughed up £100 to have one made (silly me, I know).
Is it just that a dac is more suited to switched mode-no radio frequency issues?

leo
09-03-2009, 19:42
I am sure you are right Leo but when I looked into this for my SB3 everyone said linear was the way to go and I coughed up £100 to have one made (silly me, I know).
Is it just that a dac is more suited to switched mode-no radio frequency issues?

When I say regulations I mean these new environmental green friendly regulations which apply to electronic manufacturing, things like using ROHS compliant parts (lead free) and using SMPS which are more efficient than linears

SMPS's can cause problems with some hifi components, mainly things like the switching noise, the better SMPS's have switching noise at higher frequencies, these can still cause problems.
If a piece of equipment is designed to be used with a smps there is the small possibility a linear may actually sound worse with that particular equipment if its been designed to be used with SMPS's

This may not be the case at all with Stans dac but is something thats known to happen with some other gear.

You buy the dac with the SMPS and try a linear posting your thoughts if you think it sounds better or worse, the beauty with having an external supply, its easy to swap and compare;)

Theres no such thing as a perfect SMPS, they are getting better though, as long as the equipments been designed to deal with the switching noises etc it shouldn't be a problem

StanleyB
09-03-2009, 19:47
Correct me if I'm wrong Stan but I'd imagine supplying the dac with a linear supply would add a huge increase in price?
It's cheaper to make, but more expensive to ship. Also, linear has a couple of drawbacks. The 1st one is that I would need to develop 4 versions of 110V, 127V, 220V, 240V. The other thing is that the type of regulations circuits used in linear power supplies have not seen much progress in R&D for some decades. Then there is the EU plan to ban linear power supplies very soon.

Stan

leo
09-03-2009, 20:04
Then there is the EU plan to ban linear power supplies very soon.

Stan

See above:)

Looking good though Stan

StanleyB
09-03-2009, 20:15
See above:)

Looking good though Stan
And it won't cost a few hundred £££ like some other PSU upgrades that some equipment suppliers come up with.

I was listening to the upgraded PSU on one DAC and the TC-7510 PSU on another DAC. The bass seem to have a firmer grip on the air movement with the upgraded one. My hearing drops off above 16K so I can't accurately say how much better the HF sounds.

leo
09-03-2009, 20:30
Thats interesting, I find its mostly in the bass you hear differences when comparing various SMPS's, some types make bass more audible but don't go as low if that makes sense, a good one always sounds tighter goes lower down

If the equipment powered isn't designed for SMPS's I often hear HF sharpness, things like cymbals go splashy

Its all fun and games:eyebrows: some of these little things separate the good quality gear from the not so good stuff

roscoeiii
10-03-2009, 05:34
Sitting patiently in a holding pattern until the 7520 is shipping with the new PSUs.

Looking forward to a 7520 with great anticipation.

marscay
10-03-2009, 07:34
I can also confirm that through the USB port the 7520 is recognised as a seperate sound card and can not utilise the processing of game/movie audio from any other sound card you have in your system, the Kernel Sound plugin for Foobar has also refused to output sound through the USB and so the digital ouput on your pc will have to be used if you are particular about the route your audio takes, I personally have not heard any difference in the sound from the USB compared to the Coax but I'm sure some might.

Tyrone

if you want to use the USB connection with Foobar try the Asio4all driver, works very well with my 7520/7510. ;)

nice write up btw - i'm still waiting for my 7520 to settle down a bit, i have quite a revealing HiFi setup and it's still a bit shrill for my ears in the first 20-30 hours.

there's definitely more & tighter bass versus the 7510 6/4 that i've noticed so far and the midrange has improved, i agree with Tizer in that there is more meat or body to the sound.....much cleaner resolution......tbh it sounds like another power amp has been added to my gear :) i liked the 7510 but even with less than 30hours on the 7520 it's flaws are quickly shown up if you have the gear to bring out the improvements in the 7520. i can see why Stan has seemingly got unfairly treated at a certain other forum because this DAC is insane value for the money and in these harsh economic times a top quality affordable product like the 7520 is probably the giant killer they're afraid of.

i had doubts as to whether the 7520 would be much of an upgrade over the MOD21 7510 and for the price i am gobsmacked by the quality and i've still got improvements to come from the DAC itself and a PSU upgrade :lol:

Fi-Wi
10-03-2009, 19:28
Sitting patiently in a holding pattern until the 7520 is shipping with the new PSUs.

Looking forward to a 7520 with great anticipation.

Ditto here. Having 2 very sweet but also very loud kids running around, justifies the purchase a 7520! At least that will be my defence.....

Now I hope my better half will agree. :eyebrows:

Wondering when the 7520 with psu will ship.

tizer2000uk
15-03-2009, 01:53
i had doubts as to whether the 7520 would be much of an upgrade over the MOD21 7510 and for the price i am gobsmacked by the quality and i've still got improvements to come from the DAC itself and a PSU upgrade :lol:

Well I just swapped out the stock psu for a Yuasa lead acid battery (Reading 13.6v)and the sound just got kicked up a notch! Never thought the difference would be so pronounced, the soundstage has now lept further from the speakers and instruments have more weight and air around them, the sound really is more dynamic now, and the difference was better still through my Grado's. A very good upgrade until the new psu is released.

marscay
16-03-2009, 00:36
swapped the wall wart for a maplin 12-15v psu on the weekend, haven't had any time to compare properly yet but my first impression was that bass depth went up a notch with the aftermarket psu @ 13.5v - Nickelback was really rocking the place at moderate volumes and then i got that look from the mrs :doh:

drumlins4ever
16-03-2009, 01:07
Well I just swapped out the stock psu for a Yuasa lead acid battery (Reading 13.6v)and the sound just got kicked up a notch! Never thought the difference would be so pronounced, the soundstage has now lept further from the speakers and instruments have more weight and air around them, the sound really is more dynamic now, and the difference was better still through my Grado's. A very good upgrade until the new psu is released.

No offense but you guys must have incredible ears , Its very difficult (for me) to hear the diff between the 7520 and my old CA AZUR cd player , i can hear it but only just.

I think the following plays a huge part in what we hear

http://en.wikipedia.org/wiki/Psychoacoustics

I just get VERY skeptical when people hear these huge differences between power supplies
And for your info ,i work as a pro piano tuner and musician so my ears are fairly good at listening.

Sorry if i upset anyone , the 7520 is a lovely dac for sure but c'mon get a grip lads ,,,,

StanleyB
16-03-2009, 02:09
No offense but you guys must have incredible ears , Its very difficult (for me) to hear the diff between the 7520 and my old CA AZUR cd player , i can hear it but only just.
And for your info ,i work as a pro piano tuner and musician so my ears are fairly good at listening.
A set of good ears for 'live' instruments doesn't necessarily mean a good set of ears for speakers generated audio reproduction.

tizer2000uk
16-03-2009, 13:48
No offense but you guys must have incredible ears , Its very difficult (for me) to hear the diff between the 7520 and my old CA AZUR cd player , i can hear it but only just.

I think the following plays a huge part in what we hear

http://en.wikipedia.org/wiki/Psychoacoustics

I just get VERY skeptical when people hear these huge differences between power supplies
And for your info ,i work as a pro piano tuner and musician so my ears are fairly good at listening.

Sorry if i upset anyone , the 7520 is a lovely dac for sure but c'mon get a grip lads ,,,,

Never heard the Azur but the 7510/7520 was a big leap up from my DV717 player, before the voices just seemed to float about inside the speakers, with the 7520 the singers voice gets locked in place and the soundstage sounds much larger. The unit is hidden behind the TV as there isnt any room on the rack at present and my wife had no idea it was even in the room much less installed on the stereo and she mentioned that the stereo was "sounding really good these days" When I told my wife I had installed the 7510 in the lounge she agreed it was a good purchase, she then asked how I was going to listen to my headphones in the bedroom....I then had to come clean to buying a 7520, then she wasnt so happy.

But as she had no part in the purchases and as she has no interest in hi fi she has given me some good feedback on both systems. She prefers the 7510 in the lounge as she doesnt like the extra bass from the 7520 but she picked the 7520 as having by far the best headphone amp.

On my system at least the 7520 has not really got the opportunity to shine given the budget components I use: DV717 dvd/cd player, Cambridge A1 Mk 3 amp and Tannoy Mercury F1 Custom speakers on Atacama SE24 stands.

As for the differences in power supplies, well I live very close to an industrial estate and during the day all of my kit sounds out of sorts, using the battery during the day has sorted it right out for headphone usage, at night the difference is nowhere near as pronounced.

And yes I do have very sensitive hearing, old crt tv's and monitors on their last legs drive me mad as I can hear a high pitched whistle that alot of others can't hear.

Ali Tait
16-03-2009, 13:55
Yes I hear that too! Drives me nuts sometimes.

marscay
16-03-2009, 22:30
No offense but you guys must have incredible ears , Its very difficult (for me) to hear the diff between the 7520 and my old CA AZUR cd player , i can hear it but only just.

another thing to consider is the different surroundings and equipment we all use, some are in big rooms and some aren't (me = mid sized)....some have revealing speakers (MA Gold Ref 20 = quite revealing) others have more neutral gear.....some use headphones exclusively and therefore are probably more prone to heavy variance than those with speakers - there's alot of variables.

i wouldn't call the difference between the 7510 6/4 and the 7520 night and day (that would be foolish and a disservice to the 7510) but it's more pronounced than i expected with more bass and cleaner resolution all around - without waxing lyrical it's more energetic than the 7510.....i've certainly never heard MJ's Thriller album sound so lively. can't comment about the CA Azur as i don't own one.


I just get VERY skeptical when people hear these huge differences between power supplies

i for one didn't state a huge difference when changing psu's but my first reaction was that bass felt a touch deeper, this could have been the actual DAC bedding in as i changed power after roughly 80-100hrs on the unit and until i have more time to test between the new and old it's hard for me to really gauge anything.




Sorry if i upset anyone , the 7520 is a lovely dac for sure but c'mon get a grip lads ,,,,

it's all subjective at the end of the day and i doubt you have upset anyone, only you and your ears are the things that matter.

trailer
18-03-2009, 20:13
I've just stuck a couple of 4562's into mine. Holy moly.

technobear
18-03-2009, 22:19
I've just stuck a couple of 4562's into mine. Holy moly.

If these 4562s are so much better (and Stan himself said they are) then why aren't they fitted as standard on the 7520? :scratch:

NRG
18-03-2009, 22:29
Cost vs performance

technobear
18-03-2009, 22:52
Cost vs performance

A single LM4562 can be bought retail for £4.99 on a quick search. Obviously it would be a lot cheaper in manufacturing quantities. That doesn't seem like a lot. Surely it would be worth it even if it meant the 7520 cost £4.99 extra :scratch:

StanleyB
18-03-2009, 23:08
A single LM4562 can be bought retail for £4.99 on a quick search. Obviously it would be a lot cheaper in manufacturing quantities.
The DAC1 at several times the price of the TC-7520 also use the 5532;).

I don't wish to create the illusion that one needs to dig even deeper in his or her pocket in order to get the TC-7520 to sound fantastic. The aim is to get it to be a serious contender straight out of the box. And if you wish to spend a bit more out of your own free will, you can leave the competition flat footed and show them a clean pair of heels:eyebrows:.

Spectral Morn
18-03-2009, 23:12
And yes I do have very sensitive hearing, old crt tv's and monitors on their last legs drive me mad as I can hear a high pitched whistle that alot of others can't hear.

Me three.....hate that sound. I can even hear the sound that a CRT makes when working hard to reproduce WHITE.


Regards D S D L----Neil :)

tizer2000uk
18-03-2009, 23:19
I've just stuck a couple of 4562's into mine. Holy moly.

How big a difference did they make? I should have a pair waiting for me at work. Did you replace both socketed opamps.

mrwarby
19-03-2009, 00:59
I don't wish to create the illusion that one needs to dig even deeper in his or her pocket in order to get the TC-7520 to sound fantastic. That's good to hear.
I would hope to keep it for at least 6 months before trying anything as I think it already sounds more than enough for me, maybe future updates would be to the USB. I would be quite happy to have a look though as I was using a dual trace picoscope today to fix something for work.

Anyhow, my Squeezebox is in the post, my PD-91 CD player is raring to go, my daughter has her Eee pc set up and I'm working on the mrs to buy me some headphones for my birthday and my question is, is it Ok to buy one now or wait a few months for things to settle down?

trailer
19-03-2009, 07:13
How big a difference did they make? I should have a pair waiting for me at work. Did you replace both socketed opamps.

Quite a big improvement. More detail, bigger soundstage and smoother all round.

I replaced both yes.

StanleyB
19-03-2009, 07:14
is it Ok to buy one now or wait a few months for things to settle down?
:confused:. What's happening in the next few months that needs settling down?

Covenant
19-03-2009, 08:18
Sorry to labour a point but can you confirm the replacement op-amps are not soldered-just clip out and clip in?
Are these the right ones-LM4562NA dual opamps, 8 pin DIL (MDIP) ?
Thanks
Jerry

trailer
19-03-2009, 08:20
Yes. And they're the ones I used.

Covenant
19-03-2009, 08:33
Thank Trailer. I have bought a pair off ebay for £8.99 including p&p. At that price I wont be upset if they dont make any difference. :)
Jerry

trailer
19-03-2009, 08:42
Thank Trailer. I have bought a pair off ebay for £8.99 including p&p. At that price I wont be upset if they dont make any difference. :)
Jerry

No problem. I'm just listening to mine again this morning and it really is an improvement. Smoother, more detail, better controlled bass, bigger soundstage.

Covenant
19-03-2009, 09:45
The ebay seller has just send an email thanking me for the purchase and put that the LME49720HA is even better-what do you think?
Jerry

trailer
19-03-2009, 09:50
I'm not sure if they would fit* without a bit of bending.

*height wise

StanleyB
19-03-2009, 13:09
I got the best performance from the THS4032, but it is a surface mount chip. So it needs an adapter.

NRG
19-03-2009, 13:32
The ebay seller has just send an email thanking me for the purchase and put that the LME49720HA is even better-what do you think?
Jerry

I used the LME49710 on my Alpha DAC experiment and was very impressed.

drumlins4ever
19-03-2009, 14:17
Does changing the opamps only change the sound of the headphone out ?

trailer
19-03-2009, 17:28
Does changing the opamps only change the sound of the headphone out ?

No

drumlins4ever
19-03-2009, 17:48
Apologies , i do not come from an electronic background .
So If i understand correctly , By changing the opamps one could expect a difference in sound from both the fixed and variable outputs ?

trailer
19-03-2009, 17:53
I'm no whizz neither. Stan will know better than me but I think ones for the fixed and the others for the 'phones?

StanleyB
19-03-2009, 17:55
I think ones for the fixed and the others for the 'phones?
:)

sponge
19-03-2009, 19:13
Hi Stan - Did you try the OPA2132 against the LM4562 and THS4032? If so how did it compare?
Is the 2132 a step in the right direction from the stock 5532's?

Has anyone else tried rolling any other opamps in a TC-7520?

Ken

leo
19-03-2009, 19:31
2132's are fet input based, they tend to be a little dark and smooth sounding if thats your thing:) they have lower DC offset than bipolar but if the dac uses DC coupling caps thats no issue

THS4032 is a very very good chip, as long as its stable in the used circuit (it don't like unity gain circuits even though its claimed to be ok ), this chip is almost identical topology to the AD826, just a small difference;)

leo
19-03-2009, 19:39
AD826 is good at driving headphones too;):eyebrows:

sponge
19-03-2009, 19:43
Thanks Leo - I have some 2132's - I'll give them a try.
Would you prefer the THS4032 over the LM4562? - I assume they are stable in the TC-7520 as Stan has already commented on it. They are both more or less the same price (except for the adapter) but I don't want to fork out for a couple of chips unnecessarily.

Ken

sponge
19-03-2009, 19:43
Thanks Leo - I have some 2132's - I'll give them a try.
Would you prefer the THS4032 over the LM4562? - I assume they are stable in the TC-7520 as Stan has already commented on it. They are both more or less the same price (except for the adapter) but I don't want to fork out for a couple of chips unnecessarily.

Ken

leo
19-03-2009, 19:54
Thanks Leo - I have some 2132's - I'll give them a try.
Would you prefer the THS4032 over the LM4562? - I assume they are stable in the TC-7520 as Stan has already commented on it. They are both more or less the same price (except for the adapter) but I don't want to fork out for a couple of chips unnecessarily.

Ken

Yes, give the OPA's a try, its easy to revert back if you don't like it

I don't have a TC-7520 so can't comment how the 4032's are in it I'm afraid.
I personally like the THS4032 better than LM4562 in other circuits I've used them in, it also drives capacitive loads far better.
If Stan says the THS4032 works ok in his dac you should be fine, only niggle is having to use a socket for converting SOIC to DIP, my advice if you decide to try it is remove the ceramic decoupling cap from the pcb and solder across pin4 and 8 of the converter socket as close to the THS4032 pins as possible

leo
19-03-2009, 19:57
Not meaning to stir up but the metal can LM4562 betters the plastic DIP8 version LM4562, I've compared them and the metal can sounds noticeably better to my ears, the real stinker is that they are far more expensive:(

Covenant
19-03-2009, 20:09
Oh my God-what have I got myself into? Whats the best one that will fit in the case?::doh:

leo
19-03-2009, 20:46
Oh my God-what have I got myself into? Whats the best one that will fit in the case?::doh:

I'm sure you'll have fun:lolsign:

Covenant
19-03-2009, 21:32
Well I will have a go with the 4562 and see what I think.
The 49720HA are about £12 each and are 9mm diameter and 4.5mm high with 13mm legs. I suppose the legs would need to be snipped of to suit and then soldered in.

StanleyB
20-03-2009, 07:27
My 'regular' TC-7520 uses a set of NE5532FE. But the FE is as rare as hen's teeth. I haven't seen them for sale for some years now.

I would think that for the average punter the LM4562NA would be more than sufficient. Some of the opamp choices require extreme decoupling attention. Some of them are also quite costly.

STan

Covenant
20-03-2009, 07:34
Thanks Stan,
If you come across others you think may be worth trying please let us know.
That goes for all you diy experts too!

sponge
20-03-2009, 08:09
You are quite correct Stan - The metal can LM4562 as mentioned by Leo is 20 GBP (+VAT) at the moment from Farnell - Not for the faint of heart.

I have previously tried the 49710 (single) in a PPA headphone amplifier, but it sounded a little restrained to my ears with Senn HD600's.
I'll try the OPA2132's today and I think I may place an order for a couple of THS4032's.

BTW Stan, where are the ceramic caps located that Leo mentioned, or could I get away without getting the iron out?

Cheers - Ken

StanleyB
20-03-2009, 09:16
BTW Stan, where are the ceramic caps located that Leo mentioned, or could I get away without getting the iron out?

I have put the caps right next to the opamp sockets. I don't know if the opamp sockets would affect the decoupling though. It worked OK on my PCB. I'll see if I can find the one I used. I got so many of them lying about with various mods, so finding the exact one is a challenge...

STan

sponge
20-03-2009, 09:46
I have put the caps right next to the opamp sockets.

STan

OK, I see them - Marked as MLC7 and MLC10 yes?

I guess it's worth trying a straight swap-out first as the PCB is glued in place so it's not so easy to access the underside of the board without some surgery.

Ken

SteveW
20-03-2009, 13:20
Is anyone going to re-hijack this thread?
op amps..MCL7?
I can see the lips moving but know not what it all means.

kalozois100
20-03-2009, 13:55
Is anyone going to re-hijack this thread?
op amps..MCL7?
I can see the lips moving but know not what it all means.

you could always start a new thread " mod your TC-7520" so that modders post there and leave this thread for comments on a burn't in 7520. your quite right in what you say, i being guilty as everyone else when i haven't even got one in the first place!! :doh:
Perhaps one of the admin staff can seperate modding the 7520 into another thread from this one to cater for the needs for all members.:)

trailer
20-03-2009, 15:47
Is anyone going to re-hijack this thread?
op amps..MCL7?
I can see the lips moving but know not what it all means.

Apologies SteveW I think it was me who got it off on a diversion.

leo
20-03-2009, 16:17
BTW Stan, where are the ceramic caps located that Leo mentioned, or could I get away without getting the iron out?

Cheers - Ken

Its just a precaution, a chip like the THS4032 is a fast high bandwidth beastie, sockets add more track and inductance, in some cases this added track is too far away separating the decoupling cap from the actual IC pins which can be enough to cause small stability issues
Once installed and running if it feels hot, the sound goes scratchy,bright or distorting its probably oscillating, if not it should be ok

Agreed regarding moving the modding stuff to the diy section, don't think I can do it on this part of the forum though:)

sponge
20-03-2009, 16:29
OK Leo, understood - Thanks for that. I have the OPA2132's installed at the moment and I like the sound. I wouldn't say better than the stock chips, just different in a way that I like. The order is in for the THS4032's - Fortunately I have some BrownDog's.

Also, appologies for adding to this thread - Please feel free to move it to the DIY section.

Cheers - Ken

SteveW
20-03-2009, 16:49
Its OK guys..just looking for rave reviews so that I have an excuse to get my credit card out again for my third standac !

drumlins4ever
20-03-2009, 17:07
OK Leo, understood - Thanks for that. I have the OPA2132's installed at the moment and I like the sound. I wouldn't say better than the stock chips, just different in a way that I like. The order is in for the THS4032's - Fortunately I have some BrownDog's.

Also, appologies for adding to this thread - Please feel free to move it to the DIY section.

Cheers - Ken

Care to elaborate on how the sound differs with the 2132's ?

sponge
20-03-2009, 19:43
Care to elaborate on how the sound differs with the 2132's ?

OK, I'm hopeless at describing what I hear, so please excuse me - I'll give it my best shot:

I don't know what cans you are using, so I cn only comment on the ones I use - AKG K701's and Sennheiser HD600. These are very different and suit my mood/music/whims perfectly.
The stock 5532 chip works great with the HD600's but with the K701's can sound a bit light with a hard edge in the upper treble at times which doesn't encourage a long listeneing session - A bit tiring.

However, the OPA2132's have the typical "Burr-Brown sound" - Slightly darker but (to my ears) more nicely rounded. The hard edge is gone but the detail and clarity is still there - Exactly why I bought the K701's. I'm no basshead but bass did initially sound less powerful - But I think it's because it's faster and less confused (does that make sense?). The overall effect just makes me want to keep listening.

The AKG's are not easy phones to drive and sound better through a (good) external headphone amplifier without a doubt, but every credit to the TC-7520's headamp - I am looking forward to trying the THS4032's.

Hope this has been some use.

Cheers - Ken

drumlins4ever
20-03-2009, 19:59
Yes a great help , thanks for that , sounds like the 2132's might be up my street.

Found some of these on ebay

http://cgi.ebay.co.uk/BURR-BROWN-OPA2132-OP-AMP-IC-CHIP-FOR-EFFECT-PEDALS_W0QQitemZ110339702905QQcmdZViewItemQQptZGui tar_Accessories?hash=item110339702905&_trksid=p3286.m63.l1177

But they are marked OPA2132P ,are they the same as yours ?

sponge
20-03-2009, 20:17
Yes a great help , thanks for that , sounds like the 2132's might be up my street.

But they are marked OPA2132P ,are they the same as yours ?

I tend to steer clear buying chips on Ebay - Farnell have them at £4.67 +VAT which is probably not much different than Ebay with P&P.

Mine are OPA2132PA - I dont think the differences are significant though.

Just been listening to some Santana - :) - You're going to love that Opamp!

Cheers - Ken

mrwarby
20-03-2009, 22:57
:confused:. What's happening in the next few months that needs settling down?

My apologies, I did not mean to suggest that the 7520 was not a finished product but anyone stumbling upon this thread would understandably expect to see how happy users are with this new DAC, specifically after burning it in.

I appreciate this is an enthusiasts forum but this thread seems to have moved towards discussing the subtle differences between various OpAmps. My ears do not posess enough resolving power to fully appreciate these nuances I fear. I just would like to hear how many people are happy with the sound 'as-is' to start off with.

Unless someone discovers a killer upgrade by changing a resistor value or something similar I would leave it alone for 6 months or so at least.

Covenant
21-03-2009, 08:28
I can see your point mrwarby but I suspect the differences between op-amps are more pronounced than say, between cables and look how audiophools argue about those!
Its only a bit of fun at the end of the day and its a tweak that doesn't cost a huge amount of money. :)

tizer2000uk
22-03-2009, 01:38
Another thing to remember is just because one opamp sounds great in one circuit does not guarantee happiness in another. The supporting circuitry has as much to contribute as the opamp and if it is designed to get the best out of one opamp another high end one might sound rubbish in that application.

And as for cables, I have never known a topic that has gotten people so worked up. The only thing akin to pouring petrol on the bonfire is then throwing in an opinion on double blind testing said cables...

sponge
22-03-2009, 10:01
Agreed - I guess that's why it pays to experiment. This is the fun of our hobby. Not forgetting also that people's hearing is different and their preference for a particular sound signature.

As for cables - There's no way I am going down that road!

Cheers - Ken

Fi-Wi
22-03-2009, 10:37
My apologies, I did not mean to suggest that the 7520 was not a finished product but anyone stumbling upon this thread would understandably expect to see how happy users are with this new DAC, specifically after burning it in.

I appreciate this is an enthusiasts forum but this thread seems to have moved towards discussing the subtle differences between various OpAmps.
I second that. Experimenting is great and please share your experiences but not in a thread where you would expect to read how users think that their 7520-as-they-bought-it sounds after some burning in time.

I am not a technician so opamps could be a contagious desease as far as I am concerned. A thread like this one was great for me to read about the in terms that I understand. I hope the opamp-talk will be continued in a proper thread.

trailer
28-03-2009, 16:10
I've been listening to Radio2 through a SkyHD box this afternoon into the 7520.
Thought I'd give it a go. I usually have it going through the Arcam 350 then to the 202.

Far better through the 7520. Far more reailistic and detailed and very good considering the low bitrate.