Murata regs + Caiman = Problem??

Hi! I just upgraded my Caiman with Murata regs, and I'm a bit sad with the upgrade. Both new regs (5,12v) are in place (correctly soldered).

It works, but, there is a high level background noise that was not there before. Very annoying!!

Steps already taken:

• Use a medical-grade PSU 16V (instead of 15v because of Vdrop from the diode) :: Result: NONE. Same noise.
  
• Try to put two caps 100uF 25V between pin 1 and 2 of the regs (as described in datsheet). :: Result: NONE.

Same noise is at the headphone output as at the fixed line output. Noise is the same with the GATOR on or with the original PCB.
In my (bad quality) scope it appears as a constant 20-24mv wave when you generate a test signal (-120db no matters frequency) with the computer.


I paid for the Muratas and at the end it turns out that they perform worse?? At lest regarding noise performance.

On cans, background noise is perfectly audible from 12 o'clock knob volume position.

Parts involved:
Murata 7805SR-C 0.5A max Part n: B036C
Murata 7812SR-C 0.4A max Part n: B046C

They are switching regulators, not sure why you selected those, what was your reason ?

Because I think they are recommended by Stan and many others: http://theartofsound.net/forum/showp...0&postcount=55

and they cost about 20€ not 100€ like the belleson which I prefer of course!
:(

If memory serves me well there is 1-2 guys in here with the same problem

Gazjam posted this on another forum yesterday:
"though I will be replacing the Murata 12V regulator with a Dexa UWB discreet to eliminate switching nose Im getting with the Gator in place"

When they get eyes I am sure that they will let you know... in the meanwhile you could give the search engine a spin

I never tried these particular regs but their reported to be a noticeable improvement over the stock fitted ones, maybe you have one which is faulty :confused: Do you still hear this noise without any music playing? I'd have thought they would have filtering at the switching frequency .
What noise is it ? hum, hiss, buzzing?

Quote:

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Originally Posted by slate

If memory serves me well there is 1-2 guys in here with the same problem

Gazjam posted this on another forum yesterday:
"though I will be replacing the Murata 12V regulator with a Dexa UWB discreet to eliminate switching nose Im getting with the Gator in place"

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I read it also! Thanks!!

Quote:

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Originally Posted by leo

I never tried these particular regs but their reported to be a noticeable improvement over the stock fitted ones, maybe you have one which is faulty :confused: Do you still hear this noise without any music playing? I'd have thought they would have filtering at the switching frequency .
What noise is it ? hum, hiss, buzzing?

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No, I can't hear any noise without music playing. (due to auto mute relay I suppose). It's like white noise. The typical background noise with a spike around 15 Khz

Thank you guys! I think that the only solution would be to trash the murata 12v reg...

I'll try to find out if there has been any changes in the specs of the latest Murata regs and the ones that were used initially for this mod. So keep the regulators close by in case there is a simple solution.

I can also report that I noticed this noise since I installed the Muratas about a week ago. Seems to be a problem with the Gator board only (mine is from the first batch with replaced R1 & R2 to 15k to reduce Gain), as the noise is absent when running the Caiman with the passive mod. With the passive mod the Muratas a big improvement ...

Cheers,
cz

Yup, I am having the same problem.
I recently fitted a gator board and thats when I started hearing the noise. I'd describe it as a low volume mid/high frequency "whistle".

It wasn't there with the passive mod, only with the Gator in place.

My Murata's are from the original batch of mods. Stan reckoned it was probably switching noise from teh Murata's, the noise i'm hearing being "switching noise" from the regulators.

Most folk get their Gator's to play nice with the Murata's, so maybe its system dependant? Not sure how though but its maybe a possibility.
I read here that a couple of guys had the problem and solved it by hooking up an extra cap somewhere near the Murata.
Cant remember the details sorry! Would be good if one of those guys pitched up? :)

If its switching noise...the solution might be to get a non switching regulator.
as someone said though..they are pretty pricey...

Glad its not just me thats having this problem!

*EDIT*
any chance it could be power supply dependant?
I shortened the cable on my Maplins CB Radio linear supply and Im pretty sure the noise is even louder??
odd...

I never heard this with my Caiman/Gator which had Muratas but it distorted in my system with Mk 1 Gator, Mk 2 was fine.

I moved on to an M2Tech Young which I find significantly better than the Caiman/Gator in all aspects. Night and day etc.. YMMV..

Quote:

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Originally Posted by Gazjam

Yup, I am having the same problem.
I recently fitted a gator board and thats when I started hearing the noise. I'd describe it as a low volume mid/high frequency whistle".

It wasn't there with the passive mod, only with the Gator in place.

My Murata's are from the original batch of mods. Stan reckoned it was probably switching noise from teh Murata's, the noise i'm hearing being "switching noise" from the regulators.

Most folk get their Gator's to play nice with the Murata's, so maybe its system dependant? Not sure how though but its maybe a possibility.
I read here that a couple of guys had the problem and solved it by hooking up an extra cap somewhere near the Murata.
Cant remember the details sorry! Would be good if one of those guys pitched up? :)

If its switching noise...the solution might be to get a non switching regulator.
as someone said though..they are pretty pricey...

Glad its not just me thats having this problem!

*EDIT*
any chance it could be power supply dependant?
I shortened the cable on my Maplins CB Radio linear supply and Im pretty sure the noise is even louder??
odd...

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I'm one of the persons noticed the same noise/hiss issue with Muratas..
Here is some history of my troubleshooting:

http://theartofsound.net/forum/showp...9&postcount=25

http://theartofsound.net/forum/showp...0&postcount=37

http://theartofsound.net/forum/showp...1&postcount=41

http://theartofsound.net/forum/showp...8&postcount=48

http://theartofsound.net/forum/showp...1&postcount=60


To sum it up :

1. issue is there also with original Caiman PCB, but it's more emphasized with Gator PCB and still there with Gator PCB and Gator caps mod to enhance bass drive on HD800.

2. applying caps in parallel to Murata's Vin an GND changes the behavior of the issue - instead of faint tone about 1khz on background you will get unpleasant noise into whole spectrum (audible during critical listening - it sound harsh/digitally and also on spectral analysis) - therefore i've removed the caps at the end..

3. shortening cable between PSU and caiman (to about 23cm) did not helped.

4. the same situation if using original caiman psu or laboratory linear psu

5. i've replaced Muratas by freshly delivered new Muratas directly from USA - situation still the same.. I've ordered three pairs on top of one pair I already got from Tirna, just to be sure...

6. "SOLUTION" - there is one solution which is not nice, but actually WORKS with Murata's. You have to set PSU voltage to exactly 12,9Volt . I'm in this setup for some time already and I found this the only way to get rid of the background tone/noise after fitted the Muratas into Caiman.
This have one immediately noticeable drawback - the selected input LED indicators on caiman doesn't work reliably as Caiman require 15V to work properly, but once the desired input is selected it stays there and so I can live with that. Second drawback is not so noticeable but i believe to achieve the best sound quality Caiman requires between 15 to 16 Volt.

7. My hypothesis: Murata's start do regulating only if powered with 13.0 and more Volts. Therefore setting 12.9 Volt causes that power just pass thru Muratas without any action by Muratas. Therefore I believe the tone/noise (which BTW changes frequency dependently on input voltage) is cause of Murata's regulation.

8. I'm just hobbyist and therefore not able to design solution how to filter muratas properly, but if someone would be able to find some way how to get rid of the noise produced most probably by Muratas, i would really appreciate that :) I did not want to experiment further as Caiman PCB is now quite wounded by too many soldering during replacement of the regulators, but once there would be final solution I would go for it.. I was even thinking about going back to "cheaper" LINEAR regulators ...

Fantastic post Tomas, thanks.

Sounds like you have already thought of all the "what it's" and came back to the conclusion it's switching noise from the Murata's.
Not everyone gets it though...?

I had thought about swapping for a different PSU and different things, but you saved me doing that. :)
I feel though running the Dac at a lower voltage is a bit of a compromise...might as well get it running to it's maximum potential.

Anyways, for me it's a case of swapping out the Murata for something non switching.
Just to confirm though...
I've both 12v and 5v Murata's fitted, but would I only need to swap out the 12v, as that's the one which feeds the Gator?

This would dampen the dent on the wallet if I only needed one. :)

Gaz - what Tomas has said pretty much proves that it's the 12V reg producing the noise, otherwise it would continue if the 5V one was responsible even if the input voltage were reduced to below 12.9V.

I don't have a Gator so I cannot say for certain that a 12V Dexa will cure the problem, but in passive mode there is absolutely no output whistle even if an ear is placed up to the speaker. I therefore believe that the Dexa has better noise performance than the Murata and is less likely to go into oscillation. However, if you have removed the big reservoir cap you must replace it with something to give stability close to the regs: I have 2 x 2.2uF polypropylene caps there.

OK, with my tin hat on.........

These Murata smps regs sound like they are more trouble than they are worth. I've said it time and time again, the psu is everything. Why not just push the boat out and try one of the decent linear regs out there? I believe mark from audiocom is a member here. I purchased a whole load of supereg 2's from him very cheap a while ago. They are 3 pin 78xx compatible. You could go even better and try a more expensive reg like a fidelity audio SPower (again 3 pin 78xx compatible) or even an off board reg like teddy or a more simple and much cheaper lm317 tracking pre reg (schema in the 317 datasheet or pcb's from Avondale).

Quite simply, my comments of a year ago seem to have been confirmed. Has anyone actually looked at the output and measured for noise etc.

There are affordable alternatives that have been designed with audio in mind, is it time to stop messing about saving £10 here and there and just bite the bullet??????

Thanks for that Martin, that confirms what you advised earlier about only needing a 12v reg.

I haven't replaced the big reservoir cap in my Dac,but will swap it out later.
For the moment though, will the Dexa run fine with the big cap in place?

You mentioned before that the Dexa is happier with 16v rather than the 15 I get from my Maplin linear supply, just need to source a good cheap linear supply.

UV101,

Any affordable Murata alternatives you can think of?

The Dexa reg is about £30 but it's spec looks very very good.

Gaz - be careful with increasing the voltage to 16V only because that is the big electrolytic's rating, if I remember correctly. May be better to replace it and go for 16V to ensure that the 12V has plenty of voltage drop across it.

Ian - I quite agree with you, which is why I have a SuperTeddy powering it at 16V and two high quality Dexa regulators, +12V and +5V, in place with the electrolytic replaced with large polypropylenes.

Quote:

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Originally Posted by Gazjam

UV101,

Any affordable Murata alternatives you can think of?

The Dexa reg is about £30 but it's spec looks very very good.

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78xx compatilble

Fidelity Audio SPower RRP £42 High Current (Nominal 500mA can heatsink)
Audiocom Super Reg 3 RRP £32 Low current? Unable to heatsink (Poss Mark can confirm the current rating)
HifiCollective Class D (DEXA) RRP £29.70 Unable to see current rating but looks to be heatsink mountable (Not tried these myself)
Tent Labs shunt reg €39 (approx £35) Low current (Not sure of suitability for this use)

Off board options

Super Teddy Reg €46 (approx £41) High Current
Avondale TPR2 Price to be confirmedHigh Current - I've built a couple of TPR1's and they were excellent VFM approx £5 per PCB unpopulated. Not sure on the options now as the product range looks like its being updated.

Personally I like the SPower. I now build my own modified version of this regulator. In general, most of these boutique reg use some kind of feedback to as a noise cancelling circuit.

I know I keep harping on trying to persude you to spend your hard earned cash on nice low noise regulators but there is a reason I have 4 in my Squeezebox with another 5 on the DAC I use with it and 17 in my CDP! Marco's CDP had the works at Audiocom with so his will have a few. I really is worth the investment!!!!!

Trust me.......Treat yourself!!!!!

I would personally advise against going above 16V on the power supply.

I hope to start on another round of mods soon. I even made the TC-7520SEG case 2mm higher so that I can stick my THS4032 safely in it. But in the mean time I am playing about with the standard regs and a few test mods.

Quote:

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Originally Posted by StanleyB

I would personally advise against going above 16V on the power supply.

I hope to start on another round of mods soon. I even made the TC-7520SEG case 2mm higher so that I can stick my THS4032 safely in it. But in the mean time I am playing about with the standard regs and a few test mods.

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Hi Stanley - Is there a 16v Smoother pre reg? If so, would there be an issue running a higher voltage rail if this was replaced with a suitable 25v cap for example?

~You would have to change the caps on the audio PCB to 25V or more. The headphone section is directly driven from the external power supply instead of from the 12V regulator PSU.

Quote:

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Originally Posted by MartinT

Ian - I quite agree with you, which is why I have a SuperTeddy powering it at 16V and two high quality Dexa regulators, +12V and +5V, in place with the electrolytic replaced with large polypropylenes.

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I know the superteddy is a good PSU and better than stock, obviously as you have bought one!
Is it WORTH it Martin, in bang for buck terms?

If it is..im going to do it right.

To my ears, yes. It isn't cheap to put the whole PSU together with a transformer, rectifiers, smoothing caps etc. in a case. I probably spent £100 on it in total. There's a picture story of it hereabouts.

The best sound I have achieved by far is by building two adjustable linear PSU's, one to deliver 12v and one to deliver 5v. You can then scrap the internal regulators and feed the supplies directly to the reg points.

The twin linear PSU can be built for around £120.00 if you shop around a bit and it can be as simple or as complex as you like.

I posted how to do this a while back with some photos but unfortunately can't find the thread.

I run the Caiman with this and the passive output mod through the variable outputs straight to a power amp - fantastic!

Regards

Chris

Quote:

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Originally Posted by chrism

I posted how to do this a while back with some photos but unfortunately can't find the thread.

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This http://theartofsound.net/forum/showthread.php?t=9144

[PSU+GENERAL]
Finally, I bought two Belleson SPJ Super Regulators 12V and 5V respectively...
+ More on this later... :steam:

I have also swapped all tantalum caps to Elna Silmic II and the main reservoir cap to two Elna Silmic II (2x4700uF) (Because of new 16v PSU).

This was the best upgrade I made so far. Imaging improvement is INCREDIBLE

[HEADPHONES]
Also, I swapped the op-amp for 2xLT1028ACN. Simply the best. Stunning!! (Checked against: AD797BR, OPA627, OPA827, AD8066, AD826, AD8022, ADA4627-1B,OPA2107, AD8620,OPA2107,etc.)

If you want to improve the headphones output, just throw away the AD826 for one of these: LT1028ACN, AD797BR, ADA4627-1B period.
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[REGULATORS AND NOISE]

So, when I bought the Bellesons I was very happy because I thought I was going to end forever the background noise story... (110$ pair) -140dB noise spectrum...

I soldered everything up, turned on, and... NOOOOO! The noise was still there!!! I got really upset!!

What was going on? Is it the 12V regulator?? I took the scope and started measuring again:
[BELLESON SPJ 12V]

• Fixed output: 10mVp-p background noise. Same as Murata reg. Too noisy for me
• Variable output: Unmeasurable noise till full volume: 2mVp-p then. PERFECT
• Headphones: measured 100mVp-p at the headphone output at 2-3 o'clock position of volume pot.

This translates to real world in audible background hiss from 10 o'clock position using headphones.
* Measured Dynamic range at headphone output: 90dB

So I decided to conduct more test: I took an LM340T 12V reg and soldered it a Tantalum 22uF cap Input-ground and a 0.1uF cap Ground-Output.
When I replaced the Belleson 12V regulator (59$) with a LM340T (0.76$ regulator) i repeated the test.
[LM340T]

• Fixed output: 7-8mVp-p background noise. Better but not perfect.
• Variable output: Unmeasurable noise till full volume 1mVp-p then. PERFECT AGAIN.
• Headphones: measured 18mVp-p at the headphone output at 2-3 o'clock position of volume pot. WOWWWWW!! What an improvement!!

* Measured Dynamic range at headphone output: >=100dB.
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So! What's going on?? If you use a expensive regulator Caiman+GATOR performance is MUCH WORSE (noise-wise).

Dynamic ranges:

• Murata(18$):80dB
• Belleson SR SPJ(59$):90dB
• LM340T(0.76$): >100dB

Why??? It souldn't be this way ... :scratch: I measured more and more things, but couldn't find a reason! The only repeating pattern I found was that Murata and Belleson output is >12V (12.10V) and LM340T and 7812CV is just below 12V.

Noise measured at the output of the regulatos (Murata, Belleson) is 3-1mVp-p! Where is this noise coming from??

Any ideas???

Depends on what the internal voltage reference of those regulators is like. If it's zener-like, it will regulate well but be noisy. Have you tried a Dexa in the 12V position? I don't get noise at any sensible volume level at all.

Belleson is resistor based and should be clearly 'better' than Dexa! But... it is not with the Caiman!! (http://www.belleson.com/comparenewclassd.php). I do not recommend it to Caiman users

I test noise using a special noise track I made with all spectrum freq. at or below -140dB cause under normal operation relays won't switch unless you play music so you can't test for noise.

Quote:

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Originally Posted by mcebrian

Why??? It souldn't be this way ... :scratch: I measured more and more things, but couldn't find a reason! The only repeating pattern I found was that Murata and Belleson output is >12V (12.10V) and LM340T and 7812CV is just below 12V.

Noise measured at the output of the regulatos (Murata, Belleson) is 3-1mVp-p! Where is this noise coming from??

Any ideas???

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Hi nox, seems that you've gone even further with trobuleshooting this noise issue with other than default regulators, I'm really interested once this is sorted out wat is the root cause and fix it for my Muratas :)

*EDIT* Hmm, I've just got an idea - what about putting some resistor after the 12v regulator's Vout to trim the output voltage to 12.0 ?

Quote:

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Originally Posted by mcebrian

Noise measured at the output of the regulatos (Murata, Belleson) is 3-1mVp-p! Where is this noise coming from??

Any ideas???

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I notice that the much higher performance regulators are causing you problems :scratch:

Have you possibly considered that it's not the lower noise spec of the better regulators but something to do with their much wider bandwidth that may be problematic?

Any circuitry connected to these regulators will only have a certain amount of PSRR (power supply rejection ratio) & this decreases with increasing frequency. As the super regs have a much wider bandwidth it could be possible for them to upset any circuits being powered by them at ultrasonic frequencies? Just thinking off the cuff here, it might need looking into.

What you need to remember is that the Caiman & Gator were designed to run & run well on industry standard regulators. You'd need to ask Stan if he ever substituted them for either of those you mention & if so did he test for stability?

I'd get a 100MHz oscilloscope on the rails & take a look & see what's going on if i was you ;)

I have replaced the ST L7805 reg with the Murata, mainly because I did not like the heat dissipation of the linear reg and series resistor at its input. Also the input resistor modulates the variations in current consumed from the 5v into unnecessary ripple at the input of the reg.
A side bonus with the 5v Murata, is less current counsumed from the 15v supply, which might in turn, make it less noisy. In order to reduce switching HF ripple, I have added more capacitance on the 5v.

The L7812C does not dissipate hit, as the current is moderate and the voltage drop is low. A linear reg seemd to be better choice than a switched one for that case. It was replaced with the L7812A which has 7.5X lower noise, and also better line regulation and load regulation. All that at a negligible price.
78xx data sheet: http://www.st.com/stonline/products/...re/ds/2143.pdf pages 14 Vs. 23.

Have also added protection diodes between the output and input of the regulators. As adviced at Fig 28 of the data sheet, not needed in the Caiman, but just in case.

As for the sound, it was good before and it is at list as good after the modifications. (Do not have two Caimans to do the comparison at the same time). I am happy with the end result.

Did anyone manage to solve this issue?

I installed a Gator board a couple of weeks ago and have just noticed that I now get a slight background hiss and whistle. I'm using a SuperTeddyReg linear supply, Gator board, Murata regs and every other Caiman mod including film reservoir caps.

Quote:

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Originally Posted by MartinT

Depends on what the internal voltage reference of those regulators is like. If it's zener-like, it will regulate well but be noisy. Have you tried a Dexa in the 12V position? I don't get noise at any sensible volume level at all.

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Another guy (Canetoad) put in the Dexa's instead of the Murata's with his gator and has zero background noise.

That's right. I had Muratas to go in but read a few posts about noise. I went with Dexas instead and I have zero noise. They are excellent! Cost a bit more but sound great with the Silmic IIs and the Gator board. I'm very happy! :)

If I had stayed with the passive mod I would have used the Muratas without a problem. Anybody who'd like a set of Murata regs for use with the passive mod, PM me.

Quote:

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Originally Posted by Gazjam

Another guy (Canetoad) put in the Dexa's instead of the Murata's with his gator and has zero background noise.

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Thanks.

Quote:

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Originally Posted by Canetoad

That's right. I had Muratas to go in but read a few posts about noise. I went with Dexas instead and I have zero noise. They are excellent! Cost a bit more but sound great with the Silmic IIs and the Gator board. I'm very happy! :)

If I had stayed with the passive mod I would have used the Muratas without a problem. Anybody who'd like a set of Murata regs for use with the passive mod, PM me.

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Ok thanks. That gives me some confidence but the possibility remains that you may not have had the problem even with the Murata regs, as from what I've read not everyone encounters the problem. :doh: What power supply do you use?

I was thinking about the issue today and I started to wonder if the problem could be due to the Caiman not being optimised to work with these super regulators. :scratch: Reading through the application notes for the Murata regs I noticed that it says that if you put filtering caps in parallel with the input or output they should be low esr. I haven't had chance to trace the tracks around the regs in the Caiman but it looks like there is a 220uF lytic and a small tant cap near both regs. In my Caiman the lytic caps have been swapped for Elna Silmic II. I can't find any info on the esr ratings of the Silmic II caps, so I'm wondering if their esr is a bit too high? I'm guessing the tant caps are bypassing the lytics to reduce the esr but perhaps it's not quite enough. Does anyone think this is likely to cause the issue and would swapping the Silmic II's with lower esr caps be of any benefit. :confused:

I'm currently using a Maplins CBR linear supply but am working on a replacement of my own construction based on info gained here on AOS.

My Caiman with Dexas is fed from a SuperTeddy PSU set to 16V.

Hi Martin, That's what I am going to do with my PSU. I have the STR and will be using a hexfred rectifier and 80VA tx.

How much capacitance should I use? I have a Panasonic 22000uF TSUP but it's a bit big to fit in the Maplins case. Can you explain what different values would achieve? :scratch:

I have much less than that, Bernie, primarily because I had to fit the thing into my case! The Caiman's current draw is not great (in my case, I have removed the op-amp board) and 3300uF cap of high quality (low ESR) should be fine. The STR does amazingly good regulation so you just need to ensure that the resrvoir voltage does not sag to below about 22V.

Thanks Martin and Bernie.

Martin, have you swapped the 220uF caps near the regs with Elna Silmic II's or anything else?

Dave - I swapped all my electrolytics for Elna Silmic IIs.

Quote:

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Originally Posted by MartinT

Dave - I swapped all my electrolytics for Elna Silmic IIs.

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Thanks. It sounds like you have almost the exact same setup as me with the exception of the Gator. Would you consider trying out a Gator if I sent you one? I have a spare. It would be interesting to see if you encountered the same noise issue. I'd obviously pay for the postage both ways. Cheers. :)

Sorry Dave - I removed the two board sockets and hard-soldered my passive caps in place (to retain the muting relays). I reckoned I had reached the limit of Caiman performance and have been happy with it ever since.

Quote:

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Originally Posted by MartinT

Sorry Dave - I removed the two board sockets and hard-soldered my passive caps in place (to retain the muting relays). I reckoned I had reached the limit of Caiman performance and have been happy with it ever since.

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Ah, no probs. Thanks anyway. :cool:Back to the drawing board. :hmm:

Quote:

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Originally Posted by MartinT

Dave - I swapped all my electrolytics for Elna Silmic IIs.

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Dave,

I replaced all mine with Elna Silmic II as well. I did it all at the same time. Gator I have fitted was one of the first batch made if this is any help.

This is how mine looks, with op-amp board sockets removed and AuriCaps hard-soldered in. Regulators are Dexa, reservoir caps are Panasonic film, all other electrolytics are Elna Silmic II. It sound superb driven from a SuperTeddy set to 16V.

http://www.mtc.me.uk/images/Caiman AuriCap.jpg

great pic martin,

I've ordered a set of the Dexa's to replace the Murata's

+12 Volt - DEXA-70911
+ 5 Volt - DEXA-70908

and your pic is a good help to install them.
Daft question though?

I've not looked into it yet, but off the top of your head which regulator is the 12v and which is the 5V? :mental:
I'm sure I can find it out easy enough, but just wondering if you know off the cuff?


thanks.

As far as I can remember, the one at the back is the +5V for all the DAC circuitry, the one near the front is the +12V for the op-amps. But PLEASE CHECK before going by my memory.

sure, will do.
Not wanting to quote you...just getting an idea! :)

thanks.

Quote:

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Originally Posted by MartinT

As far as I can remember, the one at the back is the +5V for all the DAC circuitry, the one near the front is the +12V for the op-amps. But PLEASE CHECK before going by my memory.

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I'm pretty sure that's correct as well. :)