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Bradhowesable
08-22-2012, 03:39 AM
So over the course of this winter all the way to this late summer I've been restoring a TR3A with my grandpa. Now that the car is running smoothly, I've started looking into some modern things to fulfill my teenager desires. :P
Basically, im looking into installing a modern audio system into this TR3... It already has a radio w/ 4 different speakers. But these were installed when my mom owner the car like 9000 years ago.. (exaggeration). Im just going to ask you guys, since im not an electrical whiz in the least bit, a couple of questions.
Heres what I need to know..

<ul style="list-style-type: disc"> Does my TR3A have a strong enough alternator to run a good sound system?
If not, is it possible to upgrade it, and what is required to do so?
Im looking at a pair of 6.5" "Kicker DS65" Speakers, but need ideas as to where to put these. my thoughts were the inside panels near where your legs go.
And finally, if anyone knows people who have done something like this, and are willing to share some contact information (email and name at most) I would be more than grateful!
[/list]
Thanks for any and all advice/answers, I'ts all greatly appreciated!

hondo402000
08-22-2012, 05:44 AM
unless it was switched out I believe your car has a generator?
it should support a modern radio, huge amp, doubt it
I dont have a TR3 but best pull the door pannel off and look to see if the speaker will fit in the door before cutting the pannels


good luck

hondo

PeterK
08-22-2012, 07:15 AM
I've got nice JBL Component GT6.5s behind the rear seats and a 40RMS amp in the boot. I drive it with a vintage Kenwood cassette.

Visually, it's hardly noticeable.

And it sounds pretty decent when the motor is stopped. But when driving, engine noise, exhaust sound, and wind, can't hear it. And actually don't want to. We just listen to the 3A and smile.

BillyB62
08-22-2012, 08:10 AM
Brad,

As mentioned above, chances are unless your car has been converted to an alternator, it has a generator. When I was choosing whether to convert my are over (which I ended up doing) I got a lot of advice from the folks here on the forum. The swap was painless and although I haven't taken advantage of the increase in amperage yet, I have bigger plans this winter. This summer is reserved for enjoying, not repairing.

Another thing you'll probably need to consider if going to modern electronics is the swap from positive to negative ground (ok, earth). Although you can still find positive grounded electronics, the majority of today's are negative.

angelfj1
08-22-2012, 09:01 AM
So over the course of this winter all the way to this late summer I've been restoring a TR3A with my grandpa. Now that the car is running smoothly, I've started looking into some modern things to fulfill my teenager desires. :P
Basically, im looking into installing a modern audio system into this TR3... It already has a radio w/ 4 different speakers. But these were installed when my mom owner the car like 9000 years ago.. (exaggeration). Im just going to ask you guys, since im not an electrical whiz in the least bit, a couple of questions.
Heres what I need to know..

<ul style="list-style-type: disc"> Does my TR3A have a strong enough alternator to run a good sound system?
If not, is it possible to upgrade it, and what is required to do so?
I'm looking at a pair of 6.5" "Kicker DS65" Speakers, but need ideas as to where to put these. my thoughts were the inside panels near where your legs go.
And finally, if anyone knows people who have done something like this, and are willing to share some contact information (email and name at most) I would be more than grateful!
[/list]
Thanks for any and all advice/answers, It's all greatly appreciated!

Bradhowesable:I'm not trying to be judgmental, but before you embark on this possibly expensive quest, understand that the best in-car system played in an open car, at speed will sound horrible. That said, if your car has been converted to an alternator its easy enough to determine the maximum capacity. If you have the original Lucas generator, capacity is very modest (approx. 19 amps). If your driving at night and have the heater blower turned on this might be marginal. Also be aware that the generator-based system is positive earthing.

JodyFKerr
08-22-2012, 10:21 AM
Here's the basics.

1). Convert the car to negative earth if you haven't already. (I haven't had a lot of coffee yet, but my foggy brain tells me this car was originally positive earth).

2). Make sure all the existing electrics work after conversion.

3). Determine the car's full electrical load (i.e. turn everything on and measure the amperage draw).

4). Determine the stereo system's amperage draw requirements.

5). That load level determines the amount of energy you'll need to produce. You will likely need to replace the generator with an alternator.

6). Test fit your stereo equipment. Make a completely separate fused wiring harness to connect all of it.

7). Hook everything up and test it.

In terms of speaker placement the most common method to boost output in these older cars is to put the best quality speakers possible into the existing speaker mounts. Then, to boost sound make a speaker box out of MDF that will sit on the parcel shelf behind the seats. Another alternative is to fit Miata seats with the built in speakers. I've also seen component stereo speakers fit where 2" tweeters are fit in the upper corners of the windshield.

Now, I've seen a lot of poorly executed stereo systems over the years, so my biggest tip to you is to think things through fully, and to not equate sound quality with the number of amps you're pushing. Excellent sound quality doesn't need massive power, and you can very easily distort the crap out of your music if you overdo it.

Jody

Adrio
08-22-2012, 10:54 AM
I have had my TR3A since I was 17 (probably about 9000 years ago as you say). At the time a stereo was high on my priority list. What I did was take one of those popular large "Blasters" that folks had back then in the 70's and put it on the passanger seat for a long trip I had to make. It was a good sound system. What I learned was I no longer cared about a stereo in the car.

It might be worth your time to borrow a portable sound system and see what it sounds like while driving before you spend any time and money on this project.

TR3driver
08-22-2012, 12:52 PM
IMO there's no need to evaluate; simply take conversion to negative ground and an alternator as a given. The stock generator will only put out 19 amps, which is barely enough for the stock configuration. (Many years ago, I discovered that the battery would actually slowly discharge while driving with the headlights, heater and wipers all on.)

I ran a modern stereo (primarily a CD-MP3 player, but I occasionally used the radio for weather reports &amp; local news while on the road) in my TR3A for quite a few years. Yes, sound quality was not the best, but with all the wind noise you'll never notice it :smile:

For me at least, there wasn't much dynamic range between the wind noise and painfully loud. My musical preference runs to classic rock, so not that much of a problem, but I sure wouldn't have wanted to listen to the 1812 Overture or anything like that.

Actually, what I enjoyed the most on the road was audio books. On a long trip, getting into a book makes the miles just fly by and, oddly enough, helps keep me awake. (Some of my favorite authors for in-car books are Terry Pratchett, Douglas Adams, Sue Grafton and Sara Paretsky. Entertaining, but don't require a lot of concentration to comprehend.)

I mounted 6.5" full range speakers in the kick panels. The passenger side on my car already had a huge hole in the sheet metal, so I cut a Masonite ring to adapt the speaker to the hole. I think later cars didn't have the hole, so that may or may not be an issue for you. The driver's side kick panel was not flat, so I had to do some sheet metal work to make a decent mounting place (in addition to cutting the hole of course). I meant to add some small tweeters under the corners of the dash, but never got around to it before the car was wrecked.

The deck was mounted in place of the glovebox, behind the door (so invisible to casual observers). There was just enough room to reach up under the dash for simple operations (like volume adjustment), or I could open the glovebox door for full access. The biggest mistake I made though, was to not block off the gap at the defroster vent. That allowed rain water to get in past the vent and into the electronics, which eventually ruined them.

Other than that, I plan to duplicate that setup on my current TR3 (when I get done with other, more pressing issues).

JodyFKerr
08-22-2012, 01:35 PM
Randall,

It all depends on what you want. We used to do competition stereos in college. That's serious business. I laid out the basic steps we followed back then. Despite engine/wind noise it is possible to get decent sound while driving, but it requires work. In part it's sound deadening, changing air flow with wind baffles, speaker placement and the amount of power running to them.

Jody

TR3driver
08-22-2012, 08:55 PM
Well, I'd guess a stock TR3 @ 75mph to be easily over 70 dB. A good orchestral piece covers about 70 dB of dynamic range, so for the faint flute passages to be audible over the wind, you're looking at some 140 dB SPL maximum (when the cannons go off if you're a fan of the 1812 Overture). Threshold of pain is 125-130 dB (and long term hearing damage sets in around 85).

And there's not a lot you can do to an open TR3 to reduce wind noise, without making significant changes to the lines of the car. Even combined upper and lower wind wings only knock the noise down a bit, from having to scream to be heard to merely yelling.

Sound deadening, speaker placement and more power are not going to change that.

Competition stereos have always struck me as kind of silly. The US Army has known since back in the 40's how to generate sound loud enough to scramble your brains ... how ya gonna top that?
https://web.archive.org/web/20010707113556/www.arl.army.mil/ARL-Directorates/ISTD/aat/MOAS.htm

Of course, that one's a bit big to install in a car, but you could put a smaller one on a trailer ... there was a prototype built ...

Bradhowesable
08-22-2012, 11:00 PM
This is a daily driver, so im not expecting to be hitting 75 on a regular basis. The car is already switched to negative, my grandfather did that when he built it a long time ago. uhm, my buddy just told me 20 amps isnt even enough to run a decent system so i think im looking at switching to an alternator. but i also heard that requires new wirings... i dont know. ill be doing more research, maybe talk to some audio professionals
Any more help is appreciated, you guys are great! Thanks!

TR3driver
08-23-2012, 03:40 AM
Wiring for an alternator isn't hard at all. In it's absolute simplest form, just run a new fairly heavy gauge wire (10 AWG will do, 8 AWG is better) from the alternator output to the hot terminal on the starter solenoid, and a smaller one from the lamp terminal to the yellow/green at the control box. Join the brown/white to the brown/blue. Join the two black wires. Remove the control box and the two original generator leads.

I chose to go a bit more complicated and ran the alternator output to the junction of the brown/white &amp; brown/blue. That way, the ammeter still reads correctly. Since the ammeter only reads to 30 amps, I added a shunt across the meter to convert it to roughly 60 amps full scale. (The loop of black insulated wire visible just below the ammeter terminals)
https://i258.photobucket.com/albums/hh260/TR3driver/TS39781LO/Ammetershunt1.jpg

DanB
08-24-2012, 01:50 PM
But if you put a modern stereo in it, can you still call it a Triumph? ; )

BillyB62
08-24-2012, 01:56 PM
Way to stir the pot Dan! :-)