Atlas GP7 w/ESU LokSound (photos and video)

[jdcolombo]

Hi Bob.

The circuitry goes literally to the edge of the board.  No shaving possible there.

I did another install today, and used a 1/4" 250-grit sanding drum in a Dremel (at lowest possible speed) to thin out the shell, and that seemed to work dandy.  It doesn't take much, and in fact the problem is that the front and rear of the shell is thicker than the center - if you just sand down the front to the same width overall as the center section, then the LokSound fits fine - snug, but fine.  I've now got this down to about a 2-hour job - the first one took me two days to figure it all out!

Now on to my RS11's.

John C.

[jdcolombo]

I second the idea ESU needs to shave about a half a mm from the width. One thing I've done when installing it in narrow hood units is to install it at an angle. This is especially easy in high nose units like your geep. Just fill the frame to an angle at the nose.

Hmmm.  There's an idea.  Hadn't thought about that, but you're right - it would be easy enough to file the frame at an angle.  But I've also found that the front and rear sections of the GP7 shell are actually thicker than the center section; if I sand down the front section to the same width as the center, then the LokSound fits OK.  Still . . . I can dream about the CT Elektronik SL76, which is 9mm wide.  If only they had US-prototype sound files . . .

John C.

[BCR 570]

John:

Unless I have missed it somewhere, can you please indicate how much material had to be removed from the frame for this installation?  I have just ordered the Micro Select 567 decoder for my NAR GP9, and laready have the speaker on hand.

Thanks,

Tim

[jdcolombo]

John:

Unless I have missed it somewhere, can you please indicate how much material had to be removed from the frame for this installation?  I have just ordered the Micro Select 567 decoder for my NAR GP9, and laready have the speaker on hand.

Thanks,

Tim

Hi Tim.

Take a look at my RS-11 install thread here:

https://www.therailwire.net/forum/index.php?topic=31391.msg347556#msg347556

The frame mods for the GP7 are almost identical to what I did for the RS11.  Descriptively, here's what I do.  First, I cut the back of the frame from the flywheel cutout to the end so that it is flush with the phosphor-bronze strip that holds the worm bearings.  DON'T GET TOO CLOSE TO THE FLYWHEEL CUTOUT (or you will cut through or crack the frame). 

In the front, I cut down the very top of the middle section of the frame (where the light board goes) so that the front of the ESU decoder will sit flush with the top of the frame.  Again, here be VERY CAREFUL when cutting so that you don't get too close to the motor mount hole (or else you will cut through/crack the frame).  Unlike the RS-11, whose frame seems to be made of some sort of VERY brittle metal, the GP7 frames seem to be more robust.  I've cut pretty close to that mounting hold without problem, but take it easy here.

Here are two additional tips that might be helpful.  First, when doing the cut around the motor mounting hole, I actually reassemble the frame with the motor and mount inside.  Then I run electrical tape around all the openings (masking tape would work fine, too) except where I'm cutting (to keep out filings) and cut both sides of the frame at once.  This helps get things even and also supports the frame so that you don't put too much pressure on it and crack it while you are cutting.  It also allows me to "test fit" the decoder as I'm cutting so that I don't cut more than absolutely necessary.   I've found that the electrical tape seals out virtually all of the filings.  When I'm done, I un-tape things, then use compressed air in a can to blow out any remaining filings.  Then I take the frame apart, reinstall the worms, and reassemble the frame.

Second, you might want to consider using the 8 x 12mm Zimo rather than the Knowles Fox for your first install.  The reason for this is that the Fox in its enclosure (if you wrap it with .020 styrene) ends up 17mm long.  It is a very close fit to avoid the plastic number board insert in the back (although you can trim this back a bit - again, see the RS-11 install thread).  The Zimo sounds nearly as good as the Fox, and will give you more room to play with without the urge to cut too close to the flywheel cutout.  Honestly, after doing the RS3, I think that if I had to do this all over again, I'd just use the Zimo in the smaller first-generation diesels, and save the Fox for the larger diesels (any six-axle, which has a longer frame and more room at the back).  It just depends on how conservative you want to be with your first installation.  The Zimo will be easier to fit (again, I remove the "sound chamber" that comes with it and build my own enclosure around it).   Plus then if you wanted to do so, you could add a "keeper" capacitor like I did on the RS3's.  Probably not required if this will be a road unit that isn't going to be doing any switching, but if you use the smaller speaker, you've got the room, and the cap would provide dropout protection "just in case."  What I'd do is mount the cap BEHIND the speaker (e.g., between the speaker and the center section of the frame, on top of the flywheel cutout; at 3mm high, it should fit upside down, so that you can attach the wires to each end; glue it to the frame with some gel CA) rather than on the front of the speaker like I did with the RS3.  It's a little more work, but not too much, and better to do this at the installation stage than to try to retrofit it later.

Third, I'm not sure you really have to cut holes in the fans for sound egress.  I didn't drill holes in the GP30 just as a "test" to see what it would sound like, and it sounded just fine.  So on the RS3, I also didn't cut holes in the fan area.  And it sounds great, too.  So I think I'd omit this step and see if you are satisfied with the result.  My theory here is that there is enough air leakage between the shell and frame that the holes don't matter much. 

Anyway, the above is a summary of my most current thinking.  My techniques have evolved a bit as I've done more of these and search for easier and more reliable ways to get it done.

John

[eja]

Instead of drilling holes between fan blades to allow the sound to escape, why not replace them with BLMA fans?  Fairly easy to do, look great and would allow more open space for the sound.

eja
(not associated with BLMA )

[BCR 570]

Does BLMA make a fan appropriate for a GP9 - I would have thought they were for more modern diesels.

Tim

[JMaurer1]

Bumping this topic back up since it is mentioned in another sound thread...

[tehachapifan]

Since this was bumped and it was one of the last bits of conversation....

Regarding opening up the shell to "let the sound out", John, what are your latest thoughts on this? My experience is you do not need to open up the shell at all and that an intact shell, acting like a secondary enclosure, can actually result in more reverb and deeper, richer sound. This is the case on my SD9 install and I also recently saw a video interview (posted here?) with Matt from ESU where he makes this exact point (although he does say something like often or sometimes). The only reason I would consider opening a shell now would be to maybe help with some kind of heating problem.

[jdcolombo]

Hi Russ.

I agree.   I no longer drill holes in the shells of anything for sound egress.

I've changed my techniques somewhat since I did this installation.  I no longer drill holes in the shell, but I DO add two 16v, 220uf tantalum chip caps for keep-alive purposes.  It's not much, but it solves about 99.9% of the sound dropout problems with reasonably clean track and wheels.  I also now put in LEDs both front and rear (603 SMT LEDs with 34-gauge magnet wire leads).   For dropping resistors, I've gone to using a small (3/8" long by 1/4" wide by 1/32" thick) piece of circuit board where I've cut through the copper to make two separate "circuits" that I solder 1K 1/8-watt SMT resistors to.  This tiny piece of circuit board takes up less space than two 1/8-watt round carbon resistors.  I've also installed ESU's newest Full Throttle sound file - there are actually TWO sound files for the EMD 567 V-16 prime mover.  The one I use is #73436 (the other one is #75411, which I don't like quite as well on the throttle-up and throttle-down sounds).  For a speaker, I use an 8x12mm in the 3d-printed Keystone Customs enclosure designed by John LeMerise.  I've also found that if I remove the heavy plastic wrap around the LokSound, it will JUST BARELY fit into the rear of the shell.  This means, however, that I need to be very careful putting kapton tape on the frame to make sure there are no opportunities for a live solder pad to contact the frame anywhere.

Here is a photo of my latest GP7 installation with the various components marked:

[ Guests cannot view attachments ]


John C.

[boisecity]

Great to see John C pushing the boundaries on N scale sound installs, a great inspiration to all of us

John F

[Ed Kapuscinski]

Great to see John C pushing the boundaries on N scale sound installs, a great inspiration to all of us

John F

Quoted for truth.

[davefoxx]

Yes, this is exciting.  I would dump all of my non-sound locomotives, but for the work that John is doing to show what can be done to existing locomotives.  I'm not sure that I can achieve what he's done, but I may be willing to try.

@jdcolombo, is there any way that you can create a parts list of what is needed (with suggestions of where to purchase the parts) if a DCC neophyte were to attempt this conversion?  I have an A&R GP7 (and an SCL GP18 on an Atlas frame) that I might be willing to take the risk of letting the magic smoke out.  I figure that if I can figure out and successfully convert these, then the slightly larger Geeps, SDs, U boats, and B boats should be a piece of cake.  I only have two locomotives with factory sound and am looking forward to adding more sound to my fleet.

DFF

[jdcolombo]

Yes, this is exciting.  I would dump all of my non-sound locomotives, but for the work that John is doing to show what can be done to existing locomotives.  I'm not sure that I can achieve what he's done, but I may be willing to try.

@jdcolombo, is there any way that you can create a parts list of what is needed (with suggestions of where to purchase the parts) if a DCC neophyte were to attempt this conversion?  I have an A&R GP7 (and an SCL GP18 on an Atlas frame) that I might be willing to take the risk of letting the magic smoke out.  I figure that if I can figure out and successfully convert these, then the slightly larger Geeps, SDs, U boats, and B boats should be a piece of cake.  I only have two locomotives with factory sound and am looking forward to adding more sound to my fleet.

DFF

Thanks for all the positive feedback.  I really hope that by doing this, I can push the manufacturers to get better at what they are doing.   We'll see.

So here's a list of stuff you will need.

1.  Soberton 8x12mm speaker.  http://www.digikey.com/product-detail/en/soberton-inc/SP-1208/433-1130-ND/6099104
2.  Enclosure for Soberton speaker (available only in 4-packs): https://www.shapeways.com/product/5L4ZXWA28/8mm-x-12mm-soberton-speaker-enclosure-4pk?optionId=60853776
3.  Two 16v, 220uf AVX tantalum chip capacitors, 10% tolerance: http://www.digikey.com/product-detail/en/avx-corporation/F931C227KNC/478-8257-1-ND/4005713
4.  Either two standard carbon resistors, 1K, 1/8-watt, or if you want to do my circuit boards with smt resistors, you will need the following PCB board and 1K, 1/8-watt smt resistors:
http://www.digikey.com/product-detail/en/stackpole-electronics-inc/CF18JT1K00/CF18JT1K00CT-ND/2022742 (standard axial resistor) OR
http://www.digikey.com/product-detail/en/panasonic-electronic-components/ERJ-6GEYJ102V/P1.0KACT-ND/42833 (chip resistor) AND
http://www.digikey.com/product-detail/en/mg-chemicals/586/473-1008-ND/559708 (PCB board, non-perforated)
5.  Two warm-white 603 LED's.  Rather than try to wire them yourself, I suggest getting them with wires already attached from Streamlined Backshop: http://store.sbs4dcc.com/sbs4dcc0603smdwarmwhiteledpre-wired38gamagnetwire.aspx
6.  A Loksound Select Micro (from Streamlined Backshop) with file #73436 installed:
http://store.sbs4dcc.com/ESU73800LokSoundSelectMicroNMRADCCSoundDecoderNEM6528-PinWiredP.aspx

For tools, you'll need some gel CA; a Dremel with a heavy-duty cutoff wheel and various sizes of carbide cutters (or a milling machine) to mill the frame; a 15-watt soldering iron with the smallest pencil tip you can find; rosin-core solder for electronics, 1/32" diameter (or 1mm); kapton tape; 1mm and 1.5 or 2mm heat shrink tubing; small wire cutters, and patience.

John C.

[seusscaboose]

when I grow up I want to be John

also... I like the kitty cat in the background...  very nice ! 

[davefoxx]

Thanks for all the positive feedback.  I really hope that by doing this, I can push the manufacturers to get better at what they are doing.   We'll see.

So here's a list of stuff you will need.

1.  Soberton 8x12mm speaker.  http://www.digikey.com/product-detail/en/soberton-inc/SP-1208/433-1130-ND/6099104
2.  Enclosure for Soberton speaker (available only in 4-packs): https://www.shapeways.com/product/5L4ZXWA28/8mm-x-12mm-soberton-speaker-enclosure-4pk?optionId=60853776
3.  Two 16v, 220uf AVX tantalum chip capacitors, 10% tolerance: http://www.digikey.com/product-detail/en/avx-corporation/F931C227KNC/478-8257-1-ND/4005713
4.  Either two standard carbon resistors, 1K, 1/8-watt, or if you want to do my circuit boards with smt resistors, you will need the following PCB board and 1K, 1/8-watt smt resistors:
http://www.digikey.com/product-detail/en/stackpole-electronics-inc/CF18JT1K00/CF18JT1K00CT-ND/2022742 (standard axial resistor) OR
http://www.digikey.com/product-detail/en/panasonic-electronic-components/ERJ-6GEYJ102V/P1.0KACT-ND/42833 (chip resistor) AND
http://www.digikey.com/product-detail/en/mg-chemicals/586/473-1008-ND/559708 (PCB board, non-perforated)
5.  Two warm-white 603 LED's.  Rather than try to wire them yourself, I suggest getting them with wires already attached from Streamlined Backshop: http://store.sbs4dcc.com/sbs4dcc0603smdwarmwhiteledpre-wired38gamagnetwire.aspx
6.  A Loksound Select Micro (from Streamlined Backshop) with file #73436 installed:
http://store.sbs4dcc.com/ESU73800LokSoundSelectMicroNMRADCCSoundDecoderNEM6528-PinWiredP.aspx

For tools, you'll need some gel CA; a Dremel with a heavy-duty cutoff wheel and various sizes of carbide cutters (or a milling machine) to mill the frame; a 15-watt soldering iron with the smallest pencil tip you can find; rosin-core solder for electronics, 1/32" diameter (or 1mm); kapton tape; 1mm and 1.5 or 2mm heat shrink tubing; small wire cutters, and patience.

John C.

John C.

@jdcolombo,

Thanks for that list!  That's very helpful.  Since I have stopped most work on the layout after burning out in the crunch time coming up to hosting the M³T, I think I'll really enjoy changing gears and attempting something like this.  Oh, and this is an excuse to finally buy a Dremel.   

DFF