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Post by liquidfantasy on Oct 6, 2009 9:26:54 GMT -5
can you notice the difference between an GE 7FDL-12 and an 7FDL-16 really clearly on the sound?
And what's about the difference between the EMD 567 turbo charged and the 645 turbo charged (both 16 cylinder)?
Reason I ask is that Soundtraxx recommends to use the 7FDL-16 instead of the 12 cylinder version and the 645 turbo charged instead of the 567 turbo charged. They clearly say that they are NOT 100% prototypical, but they would be very similar in it's appearance and therefore an alternative.
I have two B23-7's, two GP30's and two SD35's which all have currently QSI, and I just can't live with the QSI any more since I was in the USA and had my own live experience with the real thing, and QSI is so far off that, that I would love to replace it.
I honestly think that even a WRONG Tsunami might be better than a QSI, not? Or should I wait and hope that Soundtraxx ever comes along with the correct sound?
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Post by icghogger on Oct 6, 2009 10:23:46 GMT -5
I would say the sound between a 12-cylinder and a 16 cylinder is different, but not that much different.
From a simple perspective, the main difference between the GE and the EMD is the type of diesel engine used in each. EMD uses a two-cycle (intake/compression on one and power/exhaust on the other), four stroke diesel engine, while GE uses a four-cycle (suck, squeeze, bang, blow) diesel engine. This cyclic operation gives each its distinct sound. Then, to each you add the sound of the turbocharger, a high-pitched whine, which increases in frequency with each throttle notch. The EMD turbo is gear driven from idle to run 5, then it is free wheeling (exhaust-driven) above that, thus you get a variable sound to the EMD exhaust that is not as prevelant in the GE.
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Post by liquidfantasy on Oct 6, 2009 12:46:56 GMT -5
Your explanation is correct. A simple reason why ALCo's (also 4 cycle) do like to smoke that much when they notch up: The Turbo Charger is not gear driven, just by exhaust gases. When you notch it up, the engine is faster increasing the RPM's than the Turbo Charger can follow to supply oxygen which leads to an inefficient burning of the Diesel fuel resulting in black smoke. Once the TC was catching up with it's RPM's the black smoke disappears (at least it's reduced on most locos, we all know the few examples ) You also can see the same symptoms with older GE U-Boats, but not that usual as ALCo's do. I would say the sound between a 12-cylinder and a 16 cylinder is different, but not that much different. Exactly, that's what I think too, but now, how big is the difference between FDL12 and FDL16, then between 567 tc and 746 tc? thanks, D.
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Post by gtw4633 on Oct 6, 2009 14:49:52 GMT -5
Here are a couple videos for the 567 and the 645
I'm not sure what GE this one is
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Post by mrogden on Oct 6, 2009 15:42:53 GMT -5
Ohhh, that does not sound like a Gevo at all, sounds more like an ALCo.
MrOGDEN
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Post by icghogger on Oct 6, 2009 16:39:40 GMT -5
Cylinder for cylinder, the normally-aspirated (blower equipped) 567 and 645 engines would sound the same. Cylinder for cylinder, the Turbocharged 567, 645 and 710 would sound the same. Alco B engines all sound the same (for the most part). Cylinder for cylinder, FL engines sound the same. Any EMD turbo-equipped engine (regardless of the number of cylinders) would pretty much sound the same in a given throttle position. And the GEVO has its own distinct sound, for sure. The more movng parts, the more noise!! BTW, turbo-equipped 567 engines were only used in locomotives operating at 2000-2850HP, such as the GP20/30/35. The cubic displacement of the 567 limited its use in higher horsepower engines (3000 and higher), so the 645 design came into play, which was replaced by the 710, to reach the upper limits of the HP range by EMD. All this said, it really depends on a person's perspective of what an engine should sound like that would help decide how prototypical, or realistic, any sound system is. Scale locomotives would have scale sound. To me, the Tsunami module for any diesel engine sounds great, but that's only my opinion. Also, IMHO, the speaker is the key to a really good sound, even if it's only the blues.
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Post by liquidfantasy on Oct 6, 2009 18:41:37 GMT -5
@ Jay: Thanks, beside the GE Tsunami I have the 645 turbu charged too and a buddy of mine the 567 non turbo charged, so I knew the sounds.
@ Robert: Ok, taking this as an idea I could use the 645 turbo charged instead of the 567 turbo charged for my GP30's and SD 35's. Both prototypes have a 16 cylinder 567 turbo charged, so they should sound "almost" like the 645 turbo charged. But the 12 cylinder FDL should notiecable sound different than the 16 cylinder version (which is the one from Jay's 3rd video), correct?
This would mean I could equip 4 of the 6 locos with tsunami, but the two B23-7's would have to stay with QSI as long as no 12 cylinder FDL sound is available from Tsunami ...
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Post by liquidfantasy on Oct 7, 2009 4:13:14 GMT -5
Ok, I just started to use the 2 tsunamis I had at home to build in my B23-7's, should be finished tonight. I've been youtubeing last night for a while and must say that the videos having a quite good B23-7 sound are that close to the sound from Jay's video that I wouldn't be able to hear a difference between the 12 or the 16 cylinder FDL prime mover...
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