Full Version: MRC Decoder with Sound for Kato SD70MAC
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Hi All:
In additional to Big Blue, I also subscribe to Model Railroad News and have found many of their articles very informative. Recently, in October 2010 and February 2011, they had articles espousing how good an MRC decoder with sound was when installed in an N Scale Kato SD80 and a Kato SD45. Since I have a couple of Kato SD70MACs, I was eager to try the MRC decoders. BIG BIG DISAPPOINTMENT. Following is the "Letter to the Editor" that I wrote with my results. Suffice it to say, I won't be purchasing any more MRC decoders with sound until I can see and hear SIGNIFICANT improvements.
dwight77


EXTREME DISAPPOINTMENT
I eagerly read the article by Steven Goehring in your October issue, Locomotives/Rolling Stock on “Kato’s Big MAC’s a Whopper Deal” about Kato’s SD80MAC and the use of MRC’s 1808 drop-in decoder with sound. Since I have several Kato SD70’s I was hopeful that there might be good things on the horizon for sound in N Scale diesel locomotives.

In the article, Mr. Goehring reviewed the simplicity of the installation of the MRC 1808 drop-in decoder and some adjustments he made. He then stated, “When I started running the newly sound equipped SD80MAC, I knew I had a winner. It sounded fantastic and my-oh-my, how it ran!” I thought WOW; things are looking up for N Scale sound!!

Then after the holidays came your February edition and the article, again by Steven Goehring, “Kato delivers quality DCC ready SD45 to N-Scale” and in the article, the sub section “The Big New Feature DCC (and Sound!)”. Again Mr. Goehring had installed an MRC drop-in decoder with sound (#1806-2). He summarized with, “So, with DCC and sound, how does the SD45 run? VERY well, thank you very much!...The sounds are crisp and clear,...This locomotive is simply a joy to operate.”

I was ready. I checked and found that MRC had a comparable drop-in sound decoder (#1644) built especially for my Kato SD70MAC. I placed my order and eagerly awaited its arrival, presuming it would be equally as good as the ones in your articles. It arrived, and as described, the installation was quick and easy. I put my locomotive on the program track, picked a bell and horn sound and then set the prime mover sound. And then……??????......where is the sound……?????. The horn and bell were audible. To hear the diesel sound, I had to be on top of the unit. I went back to the program track to check the volume….it was maxed out. I looked at every possible adjustment but nothing improved the volume.

Bottom line, I think the speaker is just too small, not more than ¼ inch in diameter, to produce good volume….I didn’t expect to hear it from 20 feet away; but it would be nice to hear it clearly at 10’-15’. But, it just wasn’t the case in this model configuration…..a BIG BIG DISAPPOINTMENT after reading your articles.

I am going to look into possibly mounting a larger speaker in the fuel tank to see if I can salvage the decoder purchase; but at this point, I will not be purchasing nor recommending anyone purchase the MRC 1644 drop-in sound decoder for Kato’s SD70MAC. I know it is not one of the exact decoders reviewed in your articles, but I would be hard pressed to think that the results would be much different.

I greatly enjoy your magazine, please keep up the good work.
Dwight Sedgwick
North Fort Myers, Florida
This will always be the problem with sound in N-scale. You can only get so much sound out of a small speaker. Bigger speaker=bigger sound. Also, you need longer-throws and a larger surface area to get lower-frequency notes like the ones we're looking for in diesel sound. That's why you can hear the horn and bell, but the prime mover sounds so thin.

You can try putting a larger speaker in, but you will need to modify the chassis - usually by removing some of the weight. I wouldn't recommend the fuel tank, as a) it'll be a lot of work to ream out a space for the speaker, and b) you'll be picking up any magnetic debris off your layout with your loco.

If you do go the larger speaker route, you should try to make as large a sealed enclosure for the speaker as you can. If the speaker can't pressurize air, it won't work very efficiently. This is the largest problem with the MRC drop-in boards. I tried one in an HO Atlas S2 and was similarly disappointed.

You could try building an enclosure around the existing speaker, but I don't know how much space you have available in your shell.

Finally, I don't like the way MRC sets the levels of the sound options on their decoders - many sounds only having 3 levels of volume, usually ranging from silent to not loud enough. Wink

Sadly, while there are several inexpensive options for DCC sound, there are few inexpensive options for GOOD DCC sound. In my experience, if you want really good sound, you need to go to a custom install (or factory, where the chassis is designed with or as a sealed speaker enclosure) with a Soundtraxx, QSI or ESU decoder.
Good luck with the MRC decoder holding up, too. One thing they are NOT known for is reliability.

I was somewhat disappointed that MRN seemed to have succumbed to the possible pressure of upsetting a full cover advertiser. I'll wait and see what they have to say about the decoder for the Atlas Gensets - in MR they actualyl left the comment int he review that it didn;t sound right - not exactly a tough statement, but more negative than usual. Truth is, the wonderful awesome MRC decoder (just read their product literature ore one of their ads!) for the Genset isn't even remotely close to a Genset sound, it does not emulate the three prime movers starting up and shutting down based on load or anything, and the only thing new or revolutionaary about it (compared to other MRC decoders) is that all the parts seem to be securely mounted on the circuit board - a couple of their HO sound decoders have had the capacitors just kind of hanging off the board by their leads.

--Randy
Just for grins, I sent a copy of my "Letter to the Editor" to MRC to see if they had any comments. Below is my email to them and their response. It is almost too funny. To even think that they would market a sound product that they expected to be heard a whopping "almost 1 foot away" is borderline criminal.....and then it better be a silent running mechanism in your locomotive and in a dead silent room.
dwight77


----- Original Message -----
From: Frank V
To: DWIGHT SEDGWICK
Sent: Wednesday, February 23, 2011 9:46 AM
Subject: Re: MRC Decoder with sound

due to the speaker size needed for n scale the volume is not going to be that loud
normally you should be able to hear the prime mover up to almost 1 foot away...the bell and horn up to 2 feet..this also depends on gear train/mechanism noise from the loco and how quiet the room is.
if you need more volume you can use a bigger 8 ohm speaker if you can find room for it inside the loco
we can not supply a huge speaker with the decoder, because it needs to be made so everyone can install it without any major modifications to the loco

----- Original Message -----
From: DWIGHT SEDGWICK
To: <!-- e --><a href="mailto:rrtech@modelrectifier.com">rrtech@modelrectifier.com</a><!-- e -->
Sent: Tuesday, February 22, 2011 5:39 PM
Subject: MRC Decoder with sound

To: Model Rectifier Corp.

Having read two reviews in Model Railroad News which combined N Scale Kato Diesel locomotives (SD80 & SD45) with your specifically designed train decoders with sound, I was hoping for a great outcome when I purchased your #1644 decoder with sound specifically designed for my Kato SD70 locomotive.
Unfortunately, I have not had a good experience and I wrote a "Letter to the Editor" at Model Railroad News (copy below).
I felt it necessary to also send a copy of the letter to you as it is your decoder I tried to use. I would appreciate any suggestions or guidance you might provide. Your decoder was truly easy to install and it ran the locomotive fine, there just is not any volume to the sound.
Dwight Sedgwick