Coby J100u Quantum Fx J100u Boom Box Review

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(More customer reviews)Prior to purchasing this radio, I searched and searched for a detailed review of it, but found none. I basically bought the thing without an inkling of what to expect. But the mystery is over.

Now, on to the review...

The Quantum FX J-100U is one beastly looking blaster. It's huge...much bigger and heavier than I expected. It measures a whopping 17.5"W x 14"H x 6"D, easily dwarfing a GE Superadio III. It weighs slightly over 10 lbs without batteries. Much of its weight comes from its mostly wooden cabinet. There is a thick vinyl strap mounted on the top, which acts as the carry handle. The front of the radio is plastic as is the 6 "D" cell battery compartment mounted within the rear wooden panel. The radio also operates on AC, with a detachable AC cord, which plugs into the back of the radio to the right of the battery compartment. To the left of the battery compartment, there are two unused holes marked "PHONES" and "DC 9V IN". The actual headphone jack is mounted on the front of the radio. Inside the battery compartment appears to be a switch for 110/220v. It was set on 110v and I have not checked to see if the switch is functional.

Here's a rundown of the radio's features:
AM/FM/SW1/SW2
Cassette Player/Recorder
Built-in Microphone
USB/SD input
3 Band Equalizer 100Hz/1KHz/10KHz
Dual Rotating Telescoping Antennas

Here are a few other specs worth mentioning from the instruction sheet:
Max current consumption: 38mA
Max power consumption: 16W
Speaker: 30W 4 ohm 6.5 inch
Output power: 8W

But that's just about where it's impressiveness ends. Most noticeably, on the front of the radio there is what appears to be a huge 10" woofer thanks to the exaggerated speaker grille. In reality, the speaker is only 6.5". Printed around the perimeter of the speaker grille, in bold red lettering, are the words "THE ERUMPET OF THE BIG POWER/GOOD QUALITY SPEAKER/BASS REFLEX SYSTEM". I'm still puzzled as to what an "ERUMPET" is. And speaking of speakers, there are what appear to be 3 other smaller speakers, one on each top corner and one in the bottom left corner. Well, sorry to break the news, they are all fakes. The top two were easy to spot as fakes. But the lower one was less obvious due to the really nice metal speaker grille covering it. Simply by holding one's ear in front of it and not hearing any sound coming out of it was the giveaway. But also the specs in the instruction sheet only lists one speaker. By the way, the two metal looking guard bars running down each side of the front panel are plastic.

The radio has a 4-band tuner with the following frequency range for each band:
AM: 530 - 1600 KHz
FM: 88 - 108 MHz
SW1: 3.6 - 8.5 MHz
SW2: 8.5 - 22 MHz
The band is selected by a 4-position slide switch, which has a good feel to it, not too hard to slide and not too easy either. The tuner itself is another story. For one, it's almost impossible to see where dial pointer is, in part because it is recessed so far behind the tuner window, the pointer is not brightly colored, and while the tuner display itself is large, the area where the dial pointer is visible is very narrow. Secondly, the tuner tunes backwards. That is, normally when you have a slide scale tuner, the frequencies increase as you move from left to right. On this radio, the frequencies decrease moving from left to right. Though there's nothing functionally wrong with that, it is a bit disconcerting when you're used to tuning it one way all your life. Strangely, on the tuner display, they printed the words "NEW DESIGN" on it. I wonder if they're referring to the backwards tuning? Overall, AM/FM reception seems to be average, nothing exceptional. I do need to extend the dual telescoping antennas in order to get some FM stations without interference. I was able to pull in a few shortwave broadcasts, namely Radio Taiwan International and China Radio International, though the signals were prone to fading and there was a lot of hissing and whistling.

The cassette player/recorder pretty much does what its supposed to, no surprises. It has your standard functions: Record, Play, FF, REW, Stop/Eject, Pause. Does anyone still even use cassettes anymore? Anyhow, I would say it plays better than it records. It can record directly from the radio, USB/SD input, or through the built-in microphone. The built-in microphone is not very sensitive. Speaking in a normal voice, it worked best when I spoke directly in front of it. From about two feet away, it barely picked me up and from about three feet away it didn't pick up anything. And keep in mind, the player and recorder is mono only. Don't expect to be making high quality studio recordings with this.

While everything else about this radio is pretty much old school, it is updated with USB and SD card inputs mounted on the top of the radio. Through these inputs, you can playback music in digital formats. Though the box states MP3 player, the instruction sheet gives no details as to what formats are supported. The player is very basic, as it plays the files sequentially from the root directory of your USB drive or SD card. There are four function buttons that let you play/pause, repeat, go back to previous song, or skip to next song. There is no display to show artist, title, track, etc. There is only an LED indicator that lights up when you're in USB mode. While I first tried playing MP3 files just to make sure it worked, I then added some WMA files and was surprised that they also played. Pushing my luck, I then figured I'd try to see if it can play WAV files too. No dice. Oh well, two out of three ain't bad.

There are a few other things that need to be mentioned. It has a 3-band equalizer that allows you to adjust the bass, midrange, and treble. This is done through three rotary controls on the front panel. There are no position markers on the knobs so you have to guess what level you set them at unless you turn them all the way to the right or left. While you do hear changes in the sound by adjusting these knobs, there still seems to be something lacking in the sound. For example, even with the bass turned all the way up, it still sounds lacking in bass. Even with the treble turned all the way up, it still sounds lacking in treble. Maybe if they put in a real tweeter instead of that fake one it would sound better. It may make an interesting project for me someday to see if I can put one in myself.

The volume control is also very disappointing, as it goes from no volume to very loud in a very small increment. Maybe this radio was meant to be played loudly, but there should still be a better range of control. I have not tested to see exactly how loud it can go without distortion since I live in a condo and doing so would probably prompt the neighbors to call the police, but it does seem like this thing can go very loud.

Warranty? What warranty? There is no warranty mentioned whatsoever in the instruction sheet or on the box. Nor is there any manufacturer address or phone #. If you buy this thing, you're on your own.

Ending on a positive note, at least the headphone jack, while not being stereo, outputs to both the right and left sides when you plug in stereo headphones.

Bottom line, it looks impressive and has many features but doesn't do any of it exceptionally well. It puts out loud volume but the sound isn't as rich as you'd hope. The wooden cabinet is nice but the phony speakers are cheesy. I still like the way it looks though.

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