Hornby HM7000 DCC Speaker Upgrade on a Budget

[@jpkarenko6952]

Suggestion regards wiring speakers together: I would venture to say that all (American, at least) decoders will handle a 16 Ohm load with no issues. A 4 Ohm load will stress the amplifier and may cause distortion and a possible burnout at higher volume levels. Series wiring should be (+ to - to + to -) The colored wires would be hooked up Red/Black/Red/Black. If the speaker polarities are reversed, the 2 speakers will sound worse than a singleton, as they cancel each other out, sonically. I'm sure you also realize that the overall sound changes dramatically, when the locomotive shell is in place. Lastly, the baffles must be absolutely air tight, for best sound. Even the hole where the wires exit should be sealed. Nice work on the install. I'm also immensely enjoying your station build videos. Your craftsmanship and attention to detail amaze me. Cheers!

[@doubleodave]

I’d agree they don’t sound as good as the dual speaker Cavalex / Accurathrash but then again they’re no where near the price so is a good step up and are a massive improvement on the older early sound models. Hearing them in real also helps as they sound better than the microphones give them credit for 👍 Now… let me get to that link 😊👍👍

[@andydavidson9440]

A nice topic diversion Julian, thank you and it may be useful in future to refer to. It also made me appreciate the sound file and speaker set up in my Cavalex 56 that I am lucky enough to own. Keep up the great work and I look forward to the next station update.

[@Harp-House-Halt]

To quote the manual "Multiple speakers may be connected in series or parallel. However, it is important that the total speaker impedance presented to the decoder is not less than 8Ω. "

[@alyro-ls1dv]

thanks for the video. yes, the soundfile might be responsible for the sound. especially the designers of the soundfile knew what they were designing the file for. if the soundchip is reduced in sound bandwidth because someone saved money purchasing the amplifier or desingning the amplifier within, the soundfile might be cut in bandwidth during preprocessing to reduce the load of power on the original speaker. base sound is quit a lot of energy and might distort the sound a lot and even distroy the original speaker. that way equalizing and reducing bassfrequencies might already be part of hornby's design premisses. apart from all this the sound is improved, with the loco's shell on top it will even sound darker, than the separation of the two speakers in one loco won't matter so much anymore and another great. video from you.

[@Harp-House-Halt]

I think you have got that wrong ! looking at the on-line HM7000 manual, under the section relating to using two speakers they say you should NOT allow the impedance to fall below 8 Ohms ! so two in parallel without an additional 4 Ohm resistor in series is a No No. While two in series being 16 Ohms will not overload the decoder. I will post a link to the manual in a separate post just in case it gets blocked.

[@wamgoc]

Thanks for the info on alternative other than Roads and Rails.👏

[@MTMByt]

Really cool how you were able to find the supplier bro

[@anfieldroadlayoutintheloft5204]

great vid thank for share keep up the great vids and builds thanks lee

[@frazerfarey5654]

Thank you for the video, I did the very same thing , would have liked to order from roads and rails again but the cost of the speakers plus the post from the UK is to much to spend to upgrade all of my HM7000 equipped locos. Post is also free if you order over $60 AUD.

[@ianjeffery4773]

The nerd in me just loved watching the speck of dust bouncing around on the speaker. Did you try testing what a single speaker sounded like?

[@steveNCB7754]

Presumably, the sound profiles are the default ones downloaded via the Hornby app? The quality of those recordings are also a determining factor in all this, but I guess you're not in a position to try sound profiles from other suppliers, at least not without replacing the Hornby sound chip with a 'conventional' one.

[@1701_FyldeFlyer]

The 47 sounded a little distorted to me when notching up.

[@4X6GP]

Heat from your soldering iron will soften plastic insulation so you can just pull it off. No need to use teeth!