Hitachi TRK3D80 Speaker upgrade Suggestions

I have a really clean 3D80 and i would like to upgrade the sound quality. Could anyone suggest some speaker upgrades for this unit? How good is the amplifier section? Would car audio speakers be a good choice for a boombox? Has anyone damped the interior of the enclosure to reduce rattles? I love the looks of this box and simply want to modernise the sound.

I've never opened mine up. But the manual says the inner speakers are 16cm 4 ohm, and the outer speakers are 12cm 4 ohm.
It needs more bass, so maybe you could try finding inner speakers with a lower ohm rating. Of course that's assuming the amp can tolerate it.

Reli said:

I've never opened mine up. But the manual says the inner speakers are 16cm 4 ohm, and the outer speakers are 12cm 4 ohm.
It needs more bass, so maybe you could try finding inner speakers with a lower ohm rating. Of course that's assuming the amp can tolerate it.

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I think the bass is fine, but the volume is a little lacking at the top end. At lower volumes it's bass compares favourably with my other boxes. I only have 3 so small sample size.

Perrin21 said:

I have a really clean 3D80 and i would like to upgrade the sound quality. Could anyone suggest some speaker upgrades for this unit? How good is the amplifier section? Would car audio speakers be a good choice for a boombox? Has anyone damped the interior of the enclosure to reduce rattles? I love the looks of this box and simply want to modernise the sound.

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I think you need to be a little more specific about what you mean by "modernise the sound/ upgrade the sound quality." Do you mean volume? Low frequency response? High frequency response? Middle frequencies? Incidental noises (you mentioned rattles!)

I'm not being snarky as I too have a 3D80. I wish it were louder. Taking suggestions for going this route, and taking note of Reli's suggestion to use lower ohm rated speakers to improve bass.

I'm surprised the 3D80 isn't louder as the 3D7 is a screamer. It's probably my loudest mid-large sized box I've got.

In case the 3D80 is not going load you need to replace the caps on the amplifier board.
They dry out on these models.
I have 2 3d88 which have the same electronic boards and suffer from the same problem.
Even worse, the 3d circuit does not do next to nothing and the left channel is much louder than the right on.

I will do the replacement of the caps on the weekend.
From my point of view there is no need for other speakers. That would be (too) pricey compared to the value of the 3d80 - anyway the existing speakers are not bad.
I also added some foam material in the back of the body in order to close the body a bit (see pictures).

Best regards
Helmar

Original speakers are hard to upgrade or even match the standard output. The sensitivity with stock speakers can be high and resistance low which only makes it harder to find exact type. If they are working I would keep them.

Helmar said:

In case the 3D80 is not going load you need to replace the caps on the amplifier board.
They dry out on these models.
I have 2 3d88 which have the same electronic boards and suffer from the same problem.
Even worse, the 3d circuit does not do next to nothing and the left channel is much louder than the right on.

I will do the replacement of the caps on the weekend.
From my point of view there is no need for other speakers. That would be (too) pricey compared to the value of the 3d80 - anyway the existing speakers are not bad.
I also added some foam material in the back of the body in order to close the body a bit (see pictures).

Best regards
Helmar

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How difficult is recapping the amplifier? can it be upgraded to produce a higher output?

Those 4 speakers do look a little weedy...............
When compared with the original 3D7 speakers:

It's funny though, I've had speakers with tiny magnets that sounded great, and speakers with big magnets that sounded wimpy.

Yeh but the 3D7 is a powerhouse!!

The loosely suspended 8 ohm 6.5 inch woofer of the 3D7 is the key.

8 ohm? Why not 4 ohm like the others?

Reli said:

8 ohm? Why not 4 ohm like the others?

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Because the centre speaker has its own bridged amplifier (BTL) - as per the M70 set up.

jimmyjimmy19702010 said:

Yeh but the 3D7 is a powerhouse!!

The loosely suspended 8 ohm 6.5 inch woofer of the 3D7 is the key.

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I’ve had my Logitech Audiostation running next to my 3D80. It has more bass (goes to 30Hz) and much more capability from a small 10CM driver and separate tweeter. A high quality enclosure seems to be the most important feature and unfortunately the 3d80 doesn’t have that.

To complete this Hitachi Speakers excursus, see some pictures from TRK-7620 and CX-W700, which features a bandbass enclosure for the subwoofer. That leads to really low frequencies, however only at ambient volume level indoors. Once you pump up the volume, you have to lower the 3D level.

Regarding the volume level of the TRK-7620 / 3D7 it is very similar to a bose soundlink mini.
I would expect the same from a 3D80/88 however so far I did not get a 100% working one in my hand.

I'm thinking there is something wrong with your 3D7. My Bose Soundlink Mini 2 is weak when compared with my 3D7. My JBL Charge 3 is completely drowned out by my 3D7 also.

Always love it when they build a proper enclosure like that CX-W700. Stuff a bit of fiberfill in there and I bet it would slow down the waves and make it even warmer.

The construction on the CX-W is a helmholtz resonator, not an absorber. Using fiberfill could be a trial and error operation. But this is a different topic.

I drilled a hole on the woofer magnet on my CX-W700 and that got rid of the weird flappy sounds on high volume. But to do that, you have to carefully remove the dust cap (with a small utility/snap off knife for example) and seal the voice coil air gap with a tape etc.

I'd say that the enclosure is a 4th order bandpass. I filled the sealed chamber with a old school (a bit heavier) damping material from some 80's home speakers. Also added a bit to the ported enclosure. Now the bass is reeaally deep, maybe some of the mid bass is a bit tame, but boosting 300Hz helps. The damping on the ported side also dropped the acoustical low pass, or at least the low mids and the "plastic" hollow sound was gone.

A few interesting options for the "side" full range speakers. They even have chrome dustcaps!

http://ebay.to/2HA6iBj 119mm 5"inch Full-range speaker 4ohm 10W loudspeaker

http://ebay.to/2CcW6Q0 5"inch 119mm 4ohm 4Ω 15W full-range speakers Loudspeaker Ceiling speaker

Other than those, its quite hard to find 120mm speakers. Of course there are some, but at least these have the proper looks.

Hitachi 3D80.

I love this boombox so much, I have been playing it for the last couple of weeks, but it lacks "oomph." I love it's sound, it has a nice well rounded sound with a full warm lower range and bright clear highs.

Listening to "Water No Get Enemy" by Fela Kuti right now and it sounds so bloody fantastic. Of course, it's 10:15 pm so I can't crank it up at all.

But, if and when I do, the sound just "runs out of steam" as you move that volume slider past the halfway mark.

I'm tempted to buy another one, and install one of these small digital amplifiers and maybe some speakers and see if it can be made to thump mightily as befits its appearance and lower volume sound. Of course most stereos lose fidelity as you start to crank em, so I don't have high hopes. I I can't start futzing with a boombox right now, so that's a small blessing.