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Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: achalsey on February 04, 2013, 07:21:34 PM

Title: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 04, 2013, 07:21:34 PM
I forgot I did this.  Literally, I drank too much and had to be reminded several days later.  But Bryonsos' thread stirred my memory again, if anyone is interested.  First set ran through the V2, second set went straight into the 680.

1st set:  AKG CK 1X (~DIN, ~7' high, ~20' back, just LOC) > GAKable/Naiant PFA > Lunatec V2 > Tascam 680 (24/48)
2nd set: AKG CK 1X (~DIN, ~7' high, ~20' back, just LOC) > GAKable/Naiant PFA > Tascam 680 (24/48)


http://archive.org/details/NRPS2012-10-25.CK1X.V2.flac16
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: acidjack on February 04, 2013, 09:47:49 PM
Thanks for this. The more of these, the merrier :)
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: runonce on February 05, 2013, 10:33:24 AM
thanks for this...hmm...the V2 sure does have a lot more "sing" to it...
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: hi and lo on February 05, 2013, 11:35:40 AM
Thanks! I agree the more the merrier!

Since this is a very tricky comp w/ samples spread across sets, I would recommend providing unlabeled samples to eliminate some of the bias (well... I'd recommend this for any comp). Nevertheless, I appreciate you taking the time to share!
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: F.O.Bean on February 05, 2013, 12:51:52 PM
Great comp. I'd be happy with both sets! The v2 has a bit more "umph" IMO
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: stevetoney on February 05, 2013, 02:03:52 PM
I wonder if Mike Grace will come in here and bitch about your methodology.   >:D
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: F.O.Bean on February 05, 2013, 02:08:38 PM
I wonder if Mike Grace will come in here and bitch about your methodology.   >:D

 ;D 8)
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: hi and lo on February 05, 2013, 03:05:41 PM
I wonder if Mike Grace will come in here and bitch about your methodology.   >:D

No, he's too classy for that. However, he wouldn't hesitate to come into the section and tell you that your decca tree isn't setup properly... and then he'd help you fix it!
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: bryonsos on February 06, 2013, 01:14:58 AM
I like them both too. The V2 is brighter, but the 680 has a fuller bottom IMHO. I believe I'd leave the V2 at home and EQ if needed. Thanks for this!
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Gutbucket on February 06, 2013, 11:22:11 PM
Since this is a very tricky comp w/ samples spread across sets, I would recommend providing unlabeled samples to eliminate some of the bias

I didn't get a chance to listen until the next day, had forgotten which set was which at that point and then just listened before checking again.  After I heard the clear differences and easily decided on a preference I went back to see which was which. Sometimes bad memory works to one's advantage.

I wasn't suprised by my preference, though I noticed much more of a difference in here than I have running MG cadioids on-stage direct > DR680 verses > V3 > S/SPIF > DR680.  That was similarly 'compromised' by being different nights, though without the PA variables, yet the same band, layout, room, mic placement and config.  I left the V3 out of the chain to simplify things partially because I didn't hear as significant a difference as I hear with achalsey's recording, but I'm now using different mics for these gigs so maybe I'll revisit it.

It can be good to question previous conclusions, as long as some solid footing remains. Thanks for the thread.

As bryonsos notes, the next logical question is how close can some EQ come to mitigating the differences, if open to that.  In my case the MGs I used were over-bright on stage up close in the free-field and needed EQ eitherway, just different settings depending..

Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 07, 2013, 12:26:02 AM
Interesting responses everyone.  Thanks.  I will also note that I asked over in the LMA thread and streaming is only in MP3 (I didn't really realize or else would have posted flac samples), so take that for whatever its worth.

I wasn't thrilled with the music that night, and didn't even remember switching the V2 out, so honestly haven't given this much thought at all.  The brightness note though, is an interesting one.  One of my main (minor) complains about this set up is the tendency towards the brighter side of things.  I know very little about EQing so try to do it as little as possible, but there have been a couple instances where boosting some lower frequencies has produced better results (at least to me personally on my playback).  That said, it does work out most of the time since in general I've found I personally like the brighter side of the spectrum more than the opposite.

I've got a pair of 63s, have the Naiant actives coming, and only the V2 as an external preamp, so will be doing some more very informal tests with these,  the 63s, V2 and 680 soon.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: adrianf74 on February 07, 2013, 07:13:23 AM
A buddy of mine used to run AKG 48x > 680 and the recordings were good but once he added a V3 into the mix, it was night and day.  I'm sure the V2 helps it out, too.  I'll have to listen to the clips later when I'm home.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 07, 2013, 10:09:10 AM
Thanks for this.  My ears are congested, so I can't really listen.

It would be useful to repackage this as more of a comp.  Maybe make it blind, maybe break it up into some small examples that are similar in character from each source, adjust the levels to match on a per-sample basis.

Speaking generally, I find the v3 does really well on details, sound stage, 3d placement of sources (if your playback is capable of that), and instrument separation.  Those aren't things, or characteristics, that I think you can really EQ.

In fact, I'd argue that EQ tends to introduce artifiacts, and smears details and the subtle timing required to accurately recreate a detailed soundstage.  Though it may not always seem that way - a cymbal may seem more solidly fixed in the soundstage because you EQ it and bring it's frequencies up.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: bryonsos on February 07, 2013, 10:22:05 AM

In fact, I'd argue that EQ tends to introduce artifiacts, and smears details and the subtle timing required to accurately recreate a detailed soundstage.  Though it may not always seem that way - a cymbal may seem more solidly fixed in the soundstage because you EQ it and bring it's frequencies up.

This is interesting to me, I've been under the impression that you could EQ a suitably flat source to sound however you want. I hadn't thought that a pre could have that sort of influence on the overall image/soundstage on the recording.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: adrianf74 on February 07, 2013, 10:30:48 AM
@Bryonsos: Preamps often add a little sizzle or colour to a recording do I'm not surprised a V3 or V2 does. 

Even when I used to run a 9100, I could hear a small difference between running it at unity and using a battery box.  In that case, I preferred a battery box.  if there was gain involved, I liked the 9100 better.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 07, 2013, 10:55:07 AM

In fact, I'd argue that EQ tends to introduce artifiacts, and smears details and the subtle timing required to accurately recreate a detailed soundstage.  Though it may not always seem that way - a cymbal may seem more solidly fixed in the soundstage because you EQ it and bring it's frequencies up.

This is interesting to me, I've been under the impression that you could EQ a suitably flat source to sound however you want. I hadn't thought that a pre could have that sort of influence on the overall image/soundstage on the recording.

Yep, absolutely.  The algorithms that filter sound must be implemented in code.  Both the algorithm and the specific implementation can have profound impacts on lost detail.

I think those things are noticed more when you record non-PA material that has a complex soundstage.  But it also applies to PA material near or on stage.

As far as gain from a preamp, there are bunches of ways to get "gain".  Some sound better than others.

I think a few things all need to come together.  You need to have a playback system that can image in 3d.  It's funny that I put this first, but if your playback isn't capable of accurate reproduction, then you won't know how good your recordings really are, or what impact changes have on the outcome.  Also related to that is our age related hearing loss (and how we compensate!), and the overall tone of our playback.  If your playback can't resolve low frequencies well, and makes it sound muddy, then you won't want it in your recordings.

A good 2 channel playback will image way outside the speakers.  And it will have depth fore-aft.  And it might also have vertical components.  I've had a great playback for a lonngg time, but it wasn't until I switched to VR4's that the 3d thing became such a big deal.  And it also helped that I got rid of my preamp.  Eliminating that from the chain had huge benefits - jaw dropper.  There is now a large following of folks, and online communities dedicated to the practice of running DA's straight into amps (or with minimal attenuation and impedance matching, etc).

There is a lot of subtle timing and arrival information that must be accurately captured and reproduced to create that 3d soundstage.  Any processing or mathmatical operation tends to lose that detail.  And that 3d soundstage won't typically reproduce well on headphones because the two channels need to interact in free air.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Gutbucket on February 07, 2013, 11:56:17 AM
Any processing or mathmatical operation tends to lose that detail.

Not necessarily, though it certainly can do so quite easily unless done mindfully with good tools and monitoring.  Like most things in life, it's a game of degree played in shades of grey, rather than in easier to manage black & white absolutes.

For the lionshare of recordings made around here, appropriate EQ can make them better, assuming the tools, monitoring and the EQ pilot all fly right.  Done correctly the improvement can be dramatic and orders of magnitude greater than the potential negative aspects.  Doing it carefully and correctly with good tools is the key.  I think we all know how wrong it can go.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: jbell on February 07, 2013, 07:50:25 PM
If you want to hear my source, my mics were mounted 2 inches above Allyns. 

http://archive.org/details/NRPS2012-10-25.nrps_2012-10-25
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 07, 2013, 08:42:37 PM
Cool!

Just digging into these two first sets a bit, I find that one of the sources is phase reversed from the other.

Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 07, 2013, 08:58:34 PM
Cool!

Just digging into these two first sets a bit, I find that one of the sources is phase reversed from the other.

Uh oh.  This comp is falling apart.   :P  Not sure why that happened.  Would this happen if my L/R mics were mixed up?  That is a possibility.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: runonce on February 07, 2013, 09:24:00 PM
Cool!

Just digging into these two first sets a bit, I find that one of the sources is phase reversed from the other.

Uh oh.  This comp is falling apart.   :P  Not sure why that happened.  Would this happen if my L/R mics were mixed up?  That is a possibility.

I think he's comparing it to jbells source?
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 07, 2013, 09:31:47 PM
Cool!

Just digging into these two first sets a bit, I find that one of the sources is phase reversed from the other.

Uh oh.  This comp is falling apart.   :P  Not sure why that happened.  Would this happen if my L/R mics were mixed up?  That is a possibility.

I think he's comparing it to jbells source?

Yeah he is, but I'm not sure why they're reversed.  I just checked another recent source using the same equipment and they're in phase.  I'm thinking  there is a possibility my right and left mics were in the wrong input and I didn't correct it in post.  Would that cause the polarities to be reversed between the two sources?
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 07, 2013, 09:40:55 PM
This isn't an L/R error.  Someone's rig has a polarity issue on both channels.

It could simply be a cable that was soldered incorrectly.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 07, 2013, 09:48:21 PM
This isn't an L/R error.  Someone's rig has a polarity issue on both channels.

It could simply be a cable that was soldered incorrectly.

Weird.  Checked both of our Yonder sources from a couple weeks ago and they have the same polarity.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: jbell on February 08, 2013, 05:52:52 AM
Which source has the issue?? 

This isn't an L/R error.  Someone's rig has a polarity issue on both channels.

It could simply be a cable that was soldered incorrectly.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 08, 2013, 09:11:23 AM
Okay, which one of you guys put your batteries in backwards?

If we had a third source, we could use it to compare but there isn't one on archive.  Of course that wouldn't be conclusive.

One thing to look at are drum hits.  I'd expect the first peak impulses to be positive.  In the case of jmbell's source, I see that those are always negative.  So it is fairly likely that source has the polarity issue.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: jbell on February 08, 2013, 09:48:18 AM
How excatly can you tell that polarity is reversed??  If it is my source the problem would have be the Tinybox or 1/8 to 1/8 cable.  Here is another source with the same setup is the polarity off here??  I'm not understanding how you have determined this.

http://archive.org/details/ymsb2013-01-25.ymsb2013-01-25

Okay, which one of you guys put your batteries in backwards?

If we had a third source, we could use it to compare but there isn't one on archive.  Of course that wouldn't be conclusive.

One thing to look at are drum hits.  I'd expect the first peak impulses to be positive.  In the case of jmbell's source, I see that those are always negative.  So it is fairly likely that source has the polarity issue.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 08, 2013, 10:06:37 AM
The yonder source is a poor indictator because there is no percussion and no loud applause.

Sound waves are composed of rising and falling pressure gradients - the up and down you see in the waveform when you zoom way in. Up is positive, down negative.  A positive pressure should result in a positive voltage being recorded.  When the microphone diaphragm is pushed in, a positive voltage should result and be recorded.

When that positive voltage is sent to your speaker, the cone should move outward, sending that positive pressure wave.

You might try recording the clap of your hands with the m10 internal mics, and comparing it against your rig.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Ultfris101 on February 08, 2013, 10:25:33 AM
Where was there a tinybox in the rig?  OP lists PFAs on both sources?  ???

I think he's referring to Jbell's source which isn't part of comp just happened to be in same location: http://archive.org/details/NRPS2012-10-25.nrps_2012-10-25
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 08, 2013, 11:41:05 AM
Okay, this is getting off topic, but as it is an issue, I'm curious to figure it out.  Though, we both will be at Railroad Earth tomorrow with other tapers so should be able to figure it out then.

But a question about seeing polarity: with a positive polarity, that will mean the peaks will generally be positive correct?  These might not be the best examples, but here are some shots of one track from a couple weeks ago.  I thought this would be positive.  Not sure though.

http://imgur.com/a/2N2Im
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: page on February 08, 2013, 11:45:31 AM
so I got busy at work and had this composed. I'm hitting post anyway even though parts are redundant now.  :P


In fact, I'd argue that EQ tends to introduce artifiacts, and smears details and the subtle timing required to accurately recreate a detailed soundstage.  Though it may not always seem that way - a cymbal may seem more solidly fixed in the soundstage because you EQ it and bring it's frequencies up.

This is interesting to me, I've been under the impression that you could EQ a suitably flat source to sound however you want. I hadn't thought that a pre could have that sort of influence on the overall image/soundstage on the recording.

It's less of an issue with spot micing as you define placement in the soundstage later, but for "room recordings" that sort of stuff is largely set in stone when you do the placement of gear and your downstream gear is retaining detail or warping it in some way. Both approaches have benefits, it's just a personal preference issue. I agree though, EQ definitely has the potential to introduce artifacts such as smear. It's not always, and sometimes thats ok, but everything you do (including setup and gear chains through post production) will affect what you start with and what you can get later. I find it's a trade; sometimes it's worth trading detail for euphoria and smear, and other times it's not.



Okay, which one of you guys put your batteries in backwards?

If we had a third source, we could use it to compare but there isn't one on archive.  Of course that wouldn't be conclusive.

One thing to look at are drum hits.  I'd expect the first peak impulses to be positive.  In the case of jmbell's source, I see that those are always negative.  So it is fairly likely that source has the polarity issue.

How excatly can you tell that polarity is reversed??  If it is my source the problem would have be the Tinybox or 1/8 to 1/8 cable.  Here is another source with the same setup is the polarity off here??  I'm not understanding how you have determined this.

Zoom in on a drum hit. Negative polarity is generally a non-starter in terms of problems, and it's certainly fixable in post by flipping the polarity. It could have been caused by a bunch of things, a recorder preamp pin expectation, cable wiring flips, even feeding a negative voltage to capsules would induce polarity issues (I vaguely remember the lemosax could do that with some capsules unless cables were wired differently). Two things to keep in mind: 1) Keep polarity together (don't have a left channel as positive and a right as negative). You should be able to hear it, but it has a tendency to hose the soundstage of a recording. 2) Don't mix negative polarity, you end up creating nasty cancellation results. That's an oversimplification, but thats the two reasons to use positive polarity, otherwise as long as your two channels don't get mixed with another set of mics or a sbd and you keep both channels as the same polarity, it doesn't (really) matter.

But a question about seeing polarity: with a positive polarity, that will mean the peaks will generally be positive correct?  These might not be the best examples, but here are some shots of one track from a couple weeks ago.  I thought this would be positive.  Not sure though.

http://imgur.com/a/2N2Im

zoom in more. Create a sharp drum hit or hand clap and look.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Gutbucket on February 08, 2013, 12:57:30 PM
zoom in more. Create a sharp drum hit or hand clap and look.

If polarity is correct when you do this, the big initial transient peak on such a source will be seen going up before going down.  That inital transient is hard to identify on a less percussive sounds, and easier on a sharp transient if you zoom in enough.

You can check relative polarity between two mics of a stereo pair by summing them to mono and listening while inverting polarity on one of them.  The correct relative polarity will have more apparent bass.  You should be able to hear this in stereo without summing to mono as well (correct relative polarity may also sound less 'out-of-phase' up top in stereo), but it's more obvious when summing to mono.  Switching polarity and listening to the result is a good idea when mixing multiple microphones anyway, since multiple mics can be in correct relative phase but may be phase shifted in relation to each other due to different locations of the microphones and different path lenghts of sound reaching them.  'Correct' in that case is simply the choice which sounds better.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 08, 2013, 02:20:48 PM
Okay, what about this.  Three strong drum hits.

(http://i.imgur.com/xDcpldS.png?1)
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Gutbucket on February 08, 2013, 03:15:02 PM
^^
Those are definitely in correct relative polarity to each other since both go up and down at the same time.  And I think in correct absolute polarity as well, although the transients aren't especially sharp or distinct enough to be certain. But as stated previously, absolute polarity of a single pair doesn't really matter much in the real world, except to tweako audiophiles who convince themselves that it does, and the sin there tends to be disregarding other things which matter far more.  Relative polarity between channels is what really does matter, irrespective of of how many channels there are total.

Ears matter more than eyes when it comes to listening.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: jbell on February 08, 2013, 04:30:36 PM
How about the polarity of these files??  Same source as the NRPS, but different recorder DR-2d.  These are some drum hits
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: jbell on February 08, 2013, 04:52:08 PM
I only have one set of mics at the moment!!  Would I be able to tell by looking at a wave file of this being recorded with my mics??  There is no way to figure this out from looking at recordings??  Looking at the files eleven posted it is pretty clear something is going on.

It's nearly impossible to say with a program source.  Take this and playback through your system (be careful not to play too loud, it can be a little hard on tweeters), compare with a mic of known polarity because your playback system could be inverted:

http://www.naiant.com/images/rect_sine.wav
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Gutbucket on February 08, 2013, 05:04:38 PM
When trying to anylize an existing recording, you need to find a section with far sharper transients.  Look for sections which appear similar to this, before zooming in on the leading edge of a peak-

(http://www.icom.edu.my/mpt/html/kb/images_sze/3_FlexSnapToTrack_dec2011.jpg)

..and like this when you zoom in enough to decern which direction the transient goes initially (upwards or downwards- upwards in these examples, meaning positive polarity)

(http://www.0rigami.com/g/recording/pics/transient.gif)

With Jon's rectified sine sample, half of each wave is inverted so all the excursion is in the same direction from what is normally the center zero-crossing points.   If you take a look at the resulting waveform after that sample is played through your stereo and recorded with your rig, you will see a similar wave form whch is not as clean as the original, but the polarity of the signal should be apparent by zooming into any part of the waveform and comparing it's orientation to the original sample.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: jbell on February 08, 2013, 05:19:31 PM
Wavelab6 has a phase scope can that be used to determine polarity?
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Gutbucket on February 08, 2013, 06:59:45 PM
Understood.  Which is why I mentioned the waveform would appear somewhat similar, but not identical.

To be clear for others reading, there will be zero crossings in the recording of the stereo playing back the rectified sample, but as Jon notes it should be easily apparent whether the pointy bits of the waveform go downwards and the rounded bits go upwards or vice versa.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 08, 2013, 09:14:48 PM
Okay, what about this.  Three strong drum hits.

The true test is a wook with a tambourine.

Record that, and post a sample.  Then we'll know.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: it-goes-to-eleven on February 08, 2013, 09:16:52 PM
I only have one set of mics at the moment!! 

You also have the internals on your m10.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 09, 2013, 12:44:04 AM
Okay, what about this.  Three strong drum hits.

The true test is a wook with a tambourine.

Record that, and post a sample.  Then we'll know.

 ;D  Luckily during the winter there aren't too many of those indoors.  Come spring and some outdoor shows, I'll get back to you.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: Hypnocracy on February 09, 2013, 04:57:56 AM
I like them both too. The V2 is brighter, but the 680 has a fuller bottom IMHO. I believe I'd leave the V2 at home and EQ if needed. Thanks for this!

If sound were bourbon...

PFA > V2 has that Blanton's smoothness
PFA > Direct is Woodford Reserve...clean

From checking Achalsey's LMA sources...I'm gonna continue dragging the V2 to the show too...


 ;D
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: jbell on February 10, 2013, 01:57:05 PM
So we ran test on our gear at RRE last night and determined they both have the same polarity!!  Not sure what happened at the NRPS show.
Title: Re: If we're talking useless unscientific comps: V2 vs. 680 pres
Post by: achalsey on February 10, 2013, 02:46:29 PM
Top is my AKG > V2 > 680, bottom is John's MK 4 > tinybox > M10 (> 680).  They're obviously in phase with each other, and as far as I can tell, have positive polarity.

(http://i.imgur.com/KNJukEi.png?1)

Zoomed In:

(http://i.imgur.com/LysZqhh.png?1)

Different part:

(http://i.imgur.com/Y1tfclv.png?1)