Has anyone ever installed an active/passive switch into a Yamaha TRBX304?
Is it even possible?
If it is what switch recommendations would you have?
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I haven’t done it, but have heard of people bypassing the onboard preamp, so it may be possible.
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It’s totally possible and I considered doing it to mine, but really you’re better off just buying a 504 and selling the 304 instead. The 504 will feel just like the 304 to you, but lighter and better. The neck is the same.
The midrange knob is much more useful than the 5-position switch.
Here’s a similar discussion:
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I love my 304 and the only difference I see between the 304 and the 504 is the active/passive switch, and a different set of pickups. Are the 504 pickups that much better?
How is the 504 lighter? According the specs they are both mahogany.
The reason I was considering adding the switch was a difference I heard in the tone when the switch was in passive mode. It seemed to be a lot more vintage/darker in passive.
Of course this could be due to the Alnico over Ceramic pickup difference.
I am not sure if the differences between the 304 and 504 would be worth the additional $200.00 unless the alnico pickups are that much better. I know nothing about tone characteristics between alnico and ceramic.
Speaking of differences, the only difference I see between the 504 and the 604 is the body material for a $350.00 price difference over the 304 or $150.00 difference over the 504.
I do not think I could justify the $150.00 price increase of the 604 over the 504 if this body wood is the only difference. Maybe I am missing something.
I thought you had bought the 604 over the 504.
Could you please tell me why?
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Actually the 504 might not be lighter than the 304 - good point.
My 604 is a pound lighter than my 304 was.
The pickups are much more rich and less sharp sounding to me, and having a midrange control on the EQ is more useful than the selector switch on the 304.
The big differences:
304 - great intro bass for features, comes in some very cool gloss colors
504 - adds AlNiCo V pickups, Active/Passive switch, midrange control on EQ, loses preset selector, comes in subtle, more “woody” satin colors
604 - adds Alder body (much lighter and slightly brighter), flame maple top (looks amazing IMO), different preamp voicing
I would say the 504 is definitely worth the price difference over the 304. At least those are all features important to me. And of course the price difference is much, much less if you buy used (always a good idea).
Whether or not the price difference between the 604 and 504 is worth it to you is a good question. I definitely enjoy its light weight and looks.
I was saving up for a new or used 504 when my 604 went up for sale. I got it for $350, used, in perfect condition. You should be able to find used 504s in the $350 price range without issue, and may get lucky like I did with a 604.
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I agree and have decided that the 504 is the way for me to go.
In looking at the specs the only difference I see between between the 504 and 604 is the body material and looking at the colors available on the 604 I do not feel it is worth an additional $150.00 over the 504.
As far as purchasing used, where I live in rural Ontario, there is nothing available used or new right now. I guess I could find one on a US website but then I have the added expense of shipping and duties to pay and that is not worth it to me because it will add another $200+ to the price.
I thank you for your time and effort and as stated will get the TRBX504 eventually.
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That’s a great choice. It’s an excellent bass!
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Well today went very well for me and I managed to luck out and find a music shop that just took delivery of the TRBX504 and I pulled the trigger immediately and moved from a 6 month delivery to a 4 day delivery with a 10% discount and free shipping on a new TRBX504.
Perseverance pays off I guess and I have been checking twice a day, every day for the TRX504 in Canada to avoid foreign exchange and import duties for several weeks now.
I have no idea how to sell my TRBX304 that is only a month old. I know I will not sell it for less than $100Cnd (plus freight) below what I paid for it. Maybe I can start a new topic and ask for advice on selling it if that is allowed.
This will be a first for me because I have never sold/traded any of my guitars so far.
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Congrats! I bet you’ll love the 504.
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Well I have your information to thank for my decision and after seeing a video from @Jazzbass19 on Alnico vs Ceramic pickups I decided it was worth the upgrade.
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It’s a pretty serious upgrade. The 304 is a very good entry level bass; the 504 is a great all around bass.
You took exactly the same path I did out of love for my 304 
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Hi Howard, hello Celticstar,
I asked the same qustions to myself. I love the 304, but having some constrains about playing it passive - maybe also as fallback solution, if the battery is getting empty. So as I read all your communication, I figured out, that it is absolute worth to spend another few coins for the 504.
Thanks for sharing our opinions 
Alex
P.S.: found that YT video about someone, who was setting up a Yamaha TRBX504. 
Yamaha TRBX 504 Bass Guitar Fun Times
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Funny you should say that. I have my 504 in the passive mode more than 90% of the time and found that the tones I got in passive mode were what I was missing on the 304. The ceramic pickups on the 304 were just too punchy for me. My genres of interest are the Blues and R&B.
I have loosened off the strings and set the truss rod to neutral on the 304 and it is back in it’s original packaging. It was only played 4 or 5 times for a total of about 10 hours. I did try to sell it but any interested parties were only willing to pay 50% of what I paid. I did knock off $100 of what I paid but no one was interested so now it sits there as a backup.
Moving forward I will be buying another 504, which will act as a backup, and will just donate the 304 to a worthy cause.
One thing I will mention to you is that I purchased a Zoom B1X4 multi effects processor for the 504 and the combination of the 504 and the Zoom are the perfect solution for me.
I am by no means a pedal freak and and only ones I own are the Zoom B1X4, a Bass inline tuner, a Boss RC-30 loop station and a tube screamer for my electric guitars. The Zoom was quite a move for me but for the price I figured nothing ventured noting gained.
Moving to Bass from 50+ years of acoustic and electric guitar at the beginning of 2021 was quite an eye opener for me from the standpoint of the differences in equipment needed, primarily because of the Bass frequency range.
However, in the end, it is all good and I could not be happier with my setup 
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I beg to differ, so let’s play advocate of the devil for a moment.
I have a 304.
As some of you may remember, the price I bought it for secondhand suggests that
does not universally apply.
I paid 100 euros for mine… including a decent gig bag and a stand. I haven’t seen any 504’s coming by for twice that amount.
The seller, who bought it for her son, estimated that it had been played four, maybe five times.
I saw it coming by on a Dutch secondhand site, and put in a 100 euro offer, not expecting to get it. Next morning, I woke up to a message saying “come pick it up”. I told her that 100 euros was a silly amount, but she wouldn’t accept more. The only thing wrong with it was that it desperately needed a setup.
I find the lack of midrange control no issue at all – I have quite a good midrange control on my Zoom B1x Four. I can set up my amps (a gig amp which lives at the band practice site and my practice amp at home) and the Zoom pedal so that it will sound exactly like I want it to. The practice amp has a low and high midrange control, and the gig amp has a 10 band equalizer.
The only downside of the 304 is the fact that it dies when the battery dies. For that reason, I always have a charged 9V battery in the gig bag. I have yet to be caught out.
So, for a hundred bucks, I got me an excellent instrument.
There’s no question the 304 is a great bass. I loved mine.
There’s also no question the 504 is the same thing, only done quite a bit better.
Both statements can be true 
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That’s why I chimed in to balance things out a bit.
I’ll stop doing so when the first 504 comes available at, say, €150. 
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