Large Scale Central

Sierra Sound in a USA 44-Tonner

I have a few of the Sierra sound units and I wanted to put one in my USA 44-tonner. Anyone who has opened a 44-tonner knows that space is extremely limited. They also know that USA provides spaces for three speakers in the cab. One faces down in the center with a diameter of about 2-1/2", and required a really flat magnet because of the cab detail, and one in each radiator grill, with a diameter of about 1-3/4". The radiator grill speaker mounts are special in that they slide out so that you can install the speakers. They are cut for a cone and four screws in the corners. These pieces also hold the lights in place.

Even my smallest speakers were too big to fit. (Note that I even had to trim the Sierra unit to get it in.) I measured the screw distances and found pairs of what are listed as JBL speakers with the same screw spacing.

https://www.ebay.com/itm/163001299976?ul_noapp=true

When I tried to align them with the screw holes in the USA speaker frame, the spacing was right, but the headlight protrusion was in the way. Luckily, once you put the frame back in place, you can simply push the speakers up into the recess behind them for a perfect friction fit and floor clearance. Can you imagine a better fit than this?

Here you can see the pair wedged into place. They are 4 ohm so wired in series so the Sierra can take the load.

Of course the magnets now interfered with the floor weights. Rather than just remove the weights, I turned them 180 degrees and trimmed them back on my mill just enough to clear the magnets. This retains the most weight. Milling lead is an experience in itself. It doesn’t “chip” but more “melts” as you trim it.

I fit all of my Sierras with supercaps so I never need to deal with the damn battery. They tuck up to the side just above the floor weight.

And, to keep the caps from going flat when the trains park, I install a relay/cap/resistor so that the supercap will cut out of the circuit just before it goes into motorboating. This engine runs p-t-p and when the power starts, the supercaps are ready to go rather than starting from scratch each time.

Great write up… Are you happy with the sound, and do you wonder if three speakers would of improved the sound ?

In the LGB powered tender I used laptop speakers, 2 in parallel to give me 4 ohm impedance for max output of my 3 watt audio output from my decoder. These were mounted on each side between the wheels where LGB had their volume controls on sound tenders. Cut a rectungular hole with my dremel.

Sean McGillicuddy said:

Great write up… Are you happy with the sound, and do you wonder if three speakers would of improved the sound ?

I only see 2 speakers…

Greg

Greg Elmassian said:

Sean McGillicuddy said:

Great write up… Are you happy with the sound, and do you wonder if three speakers would of improved the sound ?

I only see 2 speakers…

Greg

3rd line opening post: “They also know that USA provides spaces for three speakers in the cab.”

Evelyn must be so proud.

Sean McGillicuddy said:

Great write up… Are you happy with the sound, and do you wonder if three speakers would of improved the sound ?

Very happy with the sound and I haven’t even put the cab back on (increases the bass).

Three speakers may have been better, but then I would need find one that fit in the very limited space and to deal with the impedience issue of the three speakers. Then where would I mount the sound board? These things are tighter than a crab’s azz at high tide.

I’m composing a letter of apology to Ms. Wood right now John, thanks… (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-tongue-out.gif)(I wonder how many people will get the joke?)

I would think that without baffles it might not do much but make more volume, unless you could get a significantly larger speaker in there for more bass…

When I do mine I’m going to try to seal the unit in an attempt for bass.

Greg

Greg Elmassian said:

I’m composing a letter of apology to Ms. Wood right now John, thanks… (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-tongue-out.gif)(I wonder how many people will get the joke?)

Greg

I took the class back in college. Fine for prose but not a lot of good for physics and chemistry. Got through The Hobbit quickly though. (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-wink.gif)

Well Greg since it is Woodhead, I doubt if your version will get any laffs.

Yep, concur, for reading novels ok… but you cannot speed read formulas, and they do not come in phrases. My first exposure was in the 60’s believe it or not and used a tachistoscope before that, both parents in education, so used it before the more common usage in public schools in late 60’s. Fun stuff.

Greg

 

 

Umm… more research John?

From Wikipedia:

Evelyn Nielsen Wood (January 8, 1909 – August 26, 1995) was an American educator and businessperson, widely known for coining the phrase speed reading and for creating a system to increase a reader’s speed (over the average reading rate of 250 to 300 words a minute) by a factor of two to five times, while increasing retention.[1] The system was taught in seminars as Evelyn Wood Speed Reading Dynamics, a business Wood co-founded with her husband, Doug Wood, which ultimately had over 150 outlets in the United States.[2]

Your were ahead at the first jab…

Anyway, back to the thread:

Todd, did you measure the size of the speaker cutout on the bottom?

Greg

Sorry Greg, I can only blame my love of comedy.

This explains it…