| KevinLee |
Hello everyone,
I have searched around a bit and could not find too much info on these ready made clocks.
The Audiocom clock is a version 1.1 and the LC Audio is a XO2.
Has anyone tried both of these clocks?
Does anyone have any preferances and why?
They (one of them) will be going into a NAD C541I.
I know I should try them both but it is hard to tell the difference when the re & re takes a while.
Any experiences or comments appreciated.
Cheers
KevinLee:) |
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| Hans L |
I would be very surprised if you find someone that used both. I have installed a LC Audio clock upgrade once and I was quite pleased with the results, which also included modifications to the power supply (which is probably the first place to start) and to the analog output section. I'm definately not an EE but had help from internet and friends.
I can't imagine why one ultra low jitter clock with could be audibly better or worse than similar clock. Evaluate them based on wether they have a decent seperate power supply offering. Other than that it's strictly based on the price difference. |
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| ALW |
| quote: | | I can't imagine why one ultra low jitter clock with could be audibly better or worse than similar clock. Evaluate them based on wether they have a decent seperate power supply offering. Other than that it's strictly based on the price difference. |
I'd rather evaluate them on jitter performance, in which case LCAudio were unique in providing basic jitter specs (albeit unverified).
I've used the Audiocom v1.1 and the LCAudio X0 / X02 and my ears preferred the latter. It's easy for one clock to be better from another, simply because jitter performance and spectra vary.
The Audiocom seems to pander to 'audiophile' pretensions by littering BG's around as if they are some magic panacea.
Both clocks are still sensitive to external PSU's though.
Andy. |
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| Elso Kwak |
| quote: | Originally posted by Hans L
I would be very surprised if you find someone that used both. I have installed a LC Audio clock upgrade once and I was quite pleased with the results, which also included modifications to the power supply (which is probably the first place to start) and to the analog output section. I'm definately not an EE but had help from internet and friends.
I can't imagine why one ultra low jitter clock with could be audibly better or worse than similar clock. Evaluate them based on wether they have a decent seperate power supply offering. Other than that it's strictly based on the price difference. |
Please see:
http://db.audioasylum.com/cgi/m.mpl...cal&r=&session=
Contrary to all clock mongers I found that using the player's own "raw" digital powersupply gives the best sonical results........
:cool: |
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| Hans L |
| quote: | Originally posted by ALW
I'd rather evaluate them on jitter performance, in which case LCAudio were unique in providing basic jitter specs (albeit unverified).
I've used the Audiocom v1.1 and the LCAudio X0 / X02 and my ears preferred the latter. It's easy for one clock to be better from another, simply because jitter performance and spectra vary. |
Obviously the jitter spec is important, it's the sole reason for buying a low jitter clock.
Maybe I'm assuming too much if I say that all these clocks have ultralow jitter. My experience with the LCAudio clock was that it did not deliver earthshattering performance compared to the standard clock, though there was an improvement. So therefor I assume that the differences between the ultralow jitter clock upgrades is very, very minor.
I read your post at the asylum. Guido Tent certainly knows what he's talking about, so it's good to see that his clock performed well in your tests. I listened to a presentation/lecture of him during a DIY-event this year. Very interesting stuff. Luckily Guido made sure he didn't address the group as if it were an EE-graduate class ;)
He states that the powersupply is extremely important to the proper functioning of the clock and the foundations of his argument seemed rock-solid, but I'm afraid I couldn't reproduce it here.
I wonder how your listeningtest results can be explained. Somehow a more precise readout by the player gave a more accurate but less pleasing experience. |
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| jean-paul |
| quote: | Originally posted by Hans L
Maybe I'm assuming too much if I say that all these clocks have ultralow jitter. My experience with the LCAudio clock was that it did not deliver earthshattering performance compared to the standard clock, though there was an improvement. So therefor I assume that the differences between the ultralow jitter clock upgrades are very, very minor.
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You assumed too much ;) At least not one of them sounds the same nor has it the same specs. Some of them give ( when built in right ) great improvement in certain cdplayers while others don't deliver what you've payed for.
I used the Audiocom with the special supply too and was not very impressed with its price/performance ratio.
| quote: | Originally posted by Hans L
I wonder how your listeningtest results can be explained. Somehow a more precise readout by the player gave a more accurate but less pleasing experience. |
If that is the case you know you still have work to do in the machine. Just a good clock is not enough ( I wish it was ) :( |
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| Hans L |
| quote: | Originally posted by jean-paul
You assumed too much ;) At least not one of them sounds the same nor has it the same specs. Some of them give ( when built in right ) great improvement in certain cdplayers while others don't deliver what you've payed for.
I used the Audiocom with the special supply too and was not very impressed with its price/performance ratio. |
I felt the same way about my LCAudio clock. Its price ration isn't too high either :) And this is a clock that has received a lot of positive reviews.
I still don't get it though. If the clock actually is ultralow jitter like advertised, how can it differ much from another low jitter clock, when the power supply is well built in both cases? Its only job is to clock. The only spec for the clock is jitter. If the jitter is low, the clock is a little better than a standard clock. And it should perform equally well in all players (which have the same standard clocks 99% of the time). If another clock isn't built up to spec like the LCAudio is, then it would probably sound more like a standard clock.
I think describing different low jitter clocks with different sonic signatures is stretching it a little, but then again, you don't want to get me started on cables, synergy and other vague phenomenons .... :D |
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| jean-paul |
It all depends how low "ultralow" is according manufacturers. "Very low" might be "ultralow" for some ;)
Board layout and wiring of the new clock pcb have their influence in different cdplayers and play a role in the total performance too. Also, when you feed it from the raw supply results differ from cdplayer to cdplayer. Stray RF radiated from the new clocks also differs. |
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| BrianL |
Guido's clock looks to me to be the best bang/buck. I bought the
clock oscillator by itsef w/o the accessories, though getting the
whole thing with S/PDIF reclocking might not be a bad idea. |
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| fmak |
The Audiocom seems to pander to 'audiophile' pretensions by littering BG's around as if they are some magic panacea.
Both clocks are still sensitive to external PSU's though.
Andy. [/B][/QUOTE]----------------------------------------------------------------------------------
I tend to agree; the Audiocom uses basic regulators as well.
Not only is the PS important; the type of XO is importajnt. The Tent XO and Valpey-Fisher VF XO feed less back into the PS. Chip type XOs seem poor. In this sense, a separate transformer is desirable. I have actually used a preregultor (78xx) to stop this feedthru' with some success.
It is not the clock, but the clock.digital p[rocessor and PS as a system that matters and I have found it useful to carry out on board measurements of waveform and PS noise.
:bigeyes: :bigeyes: :bigeyes: |
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| Elso Kwak |
| quote: | Originally posted by Hans L
I would be very surprised if you find someone that used both. I have installed a LC Audio clock upgrade once and I was quite pleased with the results, which also included modifications to the power supply (which is probably the first place to start) and to the analog output section. I'm definately not an EE but had help from internet and friends.
I can't imagine why one ultra low jitter clock with could be audibly better or worse than similar clock. Evaluate them based on wether they have a decent seperate power supply offering. Other than that it's strictly based on the price difference. |
Hi Hans,
I did not mean that powersupply is not important. My clock has on board low noise regulators and chokes and caps forming a PI-filter together with the main filter caps of the player's digital supply.
I also have tested various low noise regulators. Especially interesting was the following observation on two types of low noise regulators. Both regulators had equal noise specs. One sounded totally uninvolving and uninteresting the other just right. How come? Also tried with and without preregulation in my Philips CD931 and the Sony SCD-1. In both cases sound was better without preregulation.
You can download the schematic here:
http://www.diyaudio.com/forums/show...9928#post199928
:cool: |
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| Hans L |
| quote: | Originally posted by Elso Kwak
Also tried with and without preregulation in my Philips CD931 and the Sony SCD-1. In both cases sound was better without preregulation.
You can download the schematic here:
http://www.diyaudio.com/forums/show...9928#post199928
:cool: |
Hi Elso,
thanks for the link. I wasn't aware you were designing this stuff for fun :)
Any idea why a PS without preregulation sounds better? Or has this already been discussed elsewhere on the forum? |
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| Elso Kwak |
| quote: | Originally posted by Hans L
Any idea why a PS without preregulation sounds better? Or has this already been discussed elsewhere on the forum? |
Hi Hans.
My theory is that the regulators interact with each other. See also this thread on an other forum:
http://db.audioasylum.com/cgi/m.mpl...ulator&session=
:cool: |
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| Elso Kwak |
| quote: | Originally posted by fmak
The Audiocom seems to pander to 'audiophile' pretensions by littering BG's around as if they are some magic panacea.
Both clocks are still sensitive to external PSU's though.
Andy. |
Chip type XOs seem poor. In this sense, a separate transformer is desirable. I have actually used a preregultor (78xx) to stop this feedthru' with some success.
[/B][/QUOTE]The Tent clock is a chip type oscillator in a metalcan enclosure:
http://www.diyaudio.com/forums/show...11962#post11962 |
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| jean-paul |
| quote: | Originally posted by fmak
Not only is the PS important; the type of XO is important. The Tent XO and Valpey-Fisher VF XO feed less back into the PS. Chip type XOs seem poor. In this sense, a separate transformer is desirable. I have actually used a preregultor (78xx) to stop this feedthru' with some success.
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If I understand Fmak correctly the mentioned canned XO types feed less through but chip types in general are poor in that aspect.
No need for referring by incomplete quoting to a "competiting" product that happens to be a ( hint hint, wink wink ) canned type XO, Elso. People might start thinking that your clock is better ;) |
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| fmak |
The Tent clock is a chip type oscillator in a metalcan enclosure:
http://www.diyaudio.com/forums/show...11962#post11962 [/B][/QUOTE]------------------------------------------------------------------------------------
You know what I mean and I did specify the 2 can types that are better. |
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| Extreme_Boky |
I have used LC Audio XO2 clock in 4 players, all 16.9MHz, with great success. However, I replaced C1 with 3 X 2200uF / 35V FK Black Gates type, and I removed C10 + C11 + C5 and C6 and replaced with 0.1uF / 50V Nx Black Gates. This by itself was more important then clock installation in its original form.
I tried borrowing the current for the clock from existing power supply rails within the CD players, and was disappointed. I tried analogue rails, as well as digital. Installing separate transformer with fast switching / soft recovery diodes was a huge improvement. Also, I noticed that higher voltages worked better than lower ones. To me, it appeared that power supply quality had greater impact on sound than clock design in itself.
0.1uF / 50V Nx type Black Gate is an absolute champion in lowering the noise level. It does not like any by-pass capacitors, it likes to work alone! I have used it a lot in digital sections of the CD players, together with ferrite beads, to great success.
Cheers |
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| Guido Tent |
| quote: | Originally posted by Elso Kwak
Chip type XOs seem poor. In this sense, a separate transformer is desirable. I have actually used a preregultor (78xx) to stop this feedthru' with some success.
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Hi
Most chip types are poor, as are some (commercially available) discretely built clocks.
You can easilly see PS dependancy if you can measure cycle to 100k cycle jitter.
As long as you cannot measure this, all you can do is speculate.
cheers |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by KevinLee
The Audiocom clock is a version 1.1 and the LC Audio is a XO2.
Has anyone tried both of these clocks?
Does anyone have any preferances and why? |
I have tried during mods many types of clocks, most made the sound worse, not better, even when implemented carefully.
The reasons are manifold and I will only list a few common ones, like the often unavoidable introduction of added ground/noise current loops, a mismatch between clock output voltage and players logic level (many current players have 3.3V core logic supplies and levels, most if not all commercial clocks are 5V logic based) and overly long not impedance matched output wiring (losely twisted pairs) distorting the waveshape.
So, in many ways a clock replacement has to be "designed in" into the Player, rather than being a "bolt on add in" if it is supposed to work well. The reason I prefer the Tent Clock is that it is possible to implement this with a VERY TIGHT layout due to small size.
The clock can be placed only millimeters from where it's signal is needed, the supply filtering can be done using LC circuitry and you adapt the voltages with resistors as the actual output wiring. Just make sure you don't introduce ground bounce and that you tap off the 5V supply from somewhere in the player close by but low noise....
Sayonara |
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| Extreme_Boky |
Fully agree with Kuei Y. W.
I use plastic distancers (stand-offs) to place the clock PCB right on top of the holes previously occupied by xtal oscillator. The clock signal travels through no more then 20-30mm of wire. I use silver ribbons, annealed, for current transfer (power supplies), and solid core pure copper, twisted, for clock signal transfer. I always try to avoid litz cables. I get this stuff from a friend of mine who makes Hi-End cables / interconnects. It shouldn’t be difficult to obtain silver wire. Everyone should at least try playing with silver. You may like it!
Regarding Black Gates (see my previous reply above!), to me, they are the best capacitors available. Again, you can not expect just to put them wherever – take some time, try different combinations, listen and measure noise floors at each stage. Use ferrite beads to isolate stages from each other and stop rubbish reaching semiconductors through power supply lines. DIGITAL POWER SUPPLY IS IMPORTANT – do not neglect it.
Think of current runs in general, and charge / discharge current flows. Think about where you are going to connect your ground leads. Use your (analogue) CRO and measure noise levels and waveform shapes.
The implementation is everything.
Power supply is extremely important, analogue AND digital.
Avoid contact resistance whenever you can / remove connectors and solder those wires straight, HOPEFULLY at the end of modification process.
Use high quality components.
Replace cheap wiring. (With silver, if you can get it and if you are ready to pay for it).
Cheers |
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| Hans L |
You seem to know what you're talking about, so forgive my 'smartass' question: Why is a few mm of silver wire important, when surrounded by many dm of coppertrace and leads?
And a remark: 'Execution is everthing' might be a good explenation as well for a lot of the differences in the audible improvements that ppl get with different clocks. |
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| Extreme_Boky |
I've used silver for the last 6 years, not only in CD players. Silver ribbons sound the best to me. Pure copper ribbons are good as well. Silver is better for valves, copper for semiconductors' gear.
Some people hate silver - it removes harmonic richness from the sound - true if you are NOT CAREFUL.
Litz wires are the worst by far....
If you haven't tried silver, replace your hook-up wiring between inputs (RCA connectors) and input selector switch / volume pot, and tell me what you think... Make sure you replaced BOTH, signal (‘plus’) AND return ('negative') input signal wires of your amplifier!!!
Or, replace the feedback wire from the output of an amplifier to differential (feedback) transistor at the input of an amp. This is equally important as the input hook-up wiring.
A bit of silver does not make too much of a difference. However, I cut-out copper tracks on CD players' PCB, and I replace them with silver ribbons. Sometimes I use shielded ribbons, sometimes I don't. These mods are very expensive, but the results are excellent!
I can easily ‘hear’ 100 mm of silver ribbons substituted in place of cheap litz interconnect hook-up wire.
A bit of a good thing always helps in the world of cost-cutting / mass-production. Even if it's 10mm.
This is my approach and many people may not agree with me.
That's okay.
Regards |
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