Record player strobe fault

[loopyloo]

G'day all.

The other day I went to Jaycar and bought one of these :

I will use it to copy my records to mp3's for my jukebox. One important feature of this unit is the strobe because I can get recordings in tune, so I can play along with my guitar, keyboard or whatever.

So,,,, the strobe doesn't work. I mean it's on, but just constantly on.
I called them up and they got me another one to swap over. Picked it up this afternoon.
And ,,,, once again the strobe doesn't work. Same thing. Must be a funny batch.
Think I'll ring head office tomorrow and see if they have an answer.

I've never looked into these thing before and so I assume a record player strobe is usually based on a 50hz trigger from the mains (zero crossing or whatever) , yet the power for this unit is only a 12vdc plug pack, so the player must have its own built in stable trigger of some sort for the strobe.

Thoughts ?

[wotnot]

That's my first thought -- IMHO the fact the strobe doesn't work, means the manufacturer doesn't care if it wrecks your vinyl every time the needle rides the groovy waves ; if you don't care about the preservation of replay quality of your records, but care about the fact the strobe isn't working, then yes -- the strobe pulses at mains AC frequency, 2 concentric rings on the platter at for 50Hz, the other 2 for 60Hz.

I'd hedge a bet, that if you did put the thing near a light flickering at mains 50Hz, you'd quickly discover the marks on the platter are fake as well =) That'd be my guess anyway.

Thoughts? If you care about your records, the quality of the recording you obtain, and the ability to be able to get the same quality audio from the vinyl next time you play it ... get your money back now.

[loopyloo]

From Jaycar's description :
This unit is a proper transcription type turntable that has a belt drive, strobe-type speed check, pitch and anti-skating control, and s-shaped arm with high quality cartridge.

The top row of dots is 33 1/3rpm @ 50hz. I counted 180 of them. So, 60(secs) divided by 33.3333333 = 1.8 (or 1 revolution takes 1.8 secs.). That means 100 dots should pass the strobe per sec.

Getting my money back is last resort cos I really want this one working. I couldn't find a good vinyl recorder elsewhere.
I already own a vinyl recorder I got years ago but the sound quality is poor, with low bass and motor hum. The new one isn't built the best as it's all plastic but the sound from it is quite good.

[Uncle Fester]

G'day all.


I will use it to copy my records to mp3's for my jukebox. One important feature of this unit is the strobe because I can get recordings in tune, so I can play along with my guitar, keyboard or whatever.

So,,,, the strobe doesn't work. I mean it's on, but just constantly on.
I called them up and they got me another one to swap over. Picked it up this afternoon.
And ,,,, once again the strobe doesn't work. Same thing. Must be a funny batch.
Think I'll ring head office tomorrow and see if they have an answer.

I've never looked into these thing before and so I assume a record player strobe is usually based on a 50hz trigger from the mains (zero crossing or whatever) , yet the power for this unit is only a 12vdc plug pack, so the player must have its own built in stable trigger of some sort for the strobe.

Thoughts ?

First of all and most importantly, you play guitar, so obviously you have a tuner, also your keyboards should be in tune so you should be able to assess if the record player is playing in tune to your tuned instruments.

If that is so then the strobe is just an optical gimmick and not relevant and not a reason to give the turntable back as it serves it purpose.
I have played in the past fine together with record players that did not have a strobe.

A strobe would be more useful if the speed can be adjusted and provide indication that it is tuned correctly.
I have used such a type of turntable in the past when I owned an upright piano that had a somewhat flat tuning.

I assume the strobe is a design flaw, maybe they forgot to provide the 50Hz to the LED as it has to be artificially generated, made in China I also assume.

If you want to light up your strobe you can connect a bright LED to a small AC transformer power pack(rare these days) with the limiting resistor and a standard diode anti parallel to the LED.

Edit: just read your second post mentioning pitch control.
I suggest you build an external strobe LED as I described above with an AC transformer.
Although if the pitch control slider has an indentation for the proper speed and it matches your tuned instrument you can still live without the strobe.

[Uncle Fester]

Oh dear, look at the review:



I have always used my two Denon turntables and a computer to digitize vinyls

[wotnot]

I have always used my two Denon turntables and a computer to digitize vinyls

Same here, I used my Technics turntable, this was many years ago...iirc, sample at DAT rates, load it into audacity, see if it's worth removing noise/pops etc, export as flac (and/or mp3) .. been thinking of selling off all my vinyl now

[Uncle Fester]

.. been thinking of selling off all my vinyl now

Never... too many fond memories when I go through them and open the covers occasionally.
When you get old those memories become all that is left.

Virtual copies are just not the same, just a convenience and like a wall of books, tangible music sources look cool.

I dare to say that in 1000 years vinyl might still outlive any digital media when it is dug out of the ground long after humans have wiped themselves themselves off this planet.

[loopyloo]

[hinekadon]

cant remember but i thought these had a 12ac supply not dc ? have a looky inside and see if it has its own rectifier and dc supply and the led is fed of the ac at 50 hz cheers don

[loopyloo]

Yeah that's what I suspected in the first place, that it would have an AC supply. But it's DC alright. Very clean and not any AC overlay at all.
Might try and get the bottom off it tomorrow for a bit of a sticky.

[mtv]

Apart from the strobe issue.......

Don't waste your $ on junk.

If sound quality is important to you, which it appears to be, put a few extra $ into it and buy a decent turntable and use audio software to capture and convert it to whatever format and bit rate you prefer.

You can adjust pitch in the software if you can't do it 'mechanically' on the turntable.

There's free audio software available, if you don't already have some.

As the other guys mentioned, I have used that method, including filtering for noise/clicks/pops, etc.

[Uncle Fester]

On the topic of filtering I would like to add that I have used both Audacity and professional filter software on forensic evidence but later versions of Audacity beats them all hands down, both in user friendliness and features.
It is amazing what you can do with it's noise floor sampling, notch filters that you can literally draw with 'rectangular' curves and it's ease of use compression.
A voice that seemed totally 'muted' with louder bird screeching could be recovered.


However these filters are very invasive when it comes to music and I prefer not to use them and rather keep the light noise floor that a record in reasonable condition might still reproduce.
I will not digitise worn or damaged records but find alternative sources and to be honest the only records I can not find from these sources are
rare Jazz albums I inherited from my father of which they are all in a pristine condition.

[wotnot]

Apart from the strobe issue.......

Don't waste your $ on junk.

If sound quality is important to you, which it appears to be, put a few extra $ into it and buy a decent turntable and use audio software to capture and convert it to whatever format and bit rate you prefer.

You can adjust pitch in the software if you can't do it 'mechanically' on the turntable.

There's free audio software available, if you don't already have some.

As the other guys mentioned, I have used that method, including filtering for noise/clicks/pops, etc.

Junk doesn't quite say it ~ I'll go with 'plastic rubbish covered in thick layers of advertising BS' ...ie; description says for cartridge/stylus type -- "Audio Technica 3600L Ruby Stylus" ...sounds impressive, now let me say it in words, that are worthy of a technical forum such as this..."Uses the cheapest, most generic cartridge known to man, that every cheap manufacturers uses, and the conical ruby stylus is the poor man's choice" In all fact, I'm not even sure Audio Technica exists anymore ...like TEAC and others, they exists in name only, and are no longer the company famed for audio innovation and quality decades ago.

As you say, apart from the strobe issue, there are so many shortfalls here, including that all the sampling/encoding is done inside the unit (so you've have limited if any control over that), and lightweight plastic turntables always taint the sound with mechanical resonance.

If one focuses on the strobe issue, I could blithely suggest everyone go for a little drivies to their nearest jaycar store, and see if they can find the OP one that has a working strobe light....however, I don't feel good about sending ppl on a fools errand, so instead I traveled to Russia (via youtube =) to see how this unit and it's strobe work there -->> Well, there you go....strobe light doesn't work, but the room lights where the video is shot -are- strobing at mains frequency, and we can see the platter isn't running at the proper fixed speed...sigh... I am so unsurprised.

Save your money, get your refund, hunt around for a 2ndhand turntable that's at least 'decent' and dedicated to it's purpose (playing vinyl records), if you want the best dynamic signal range use an elliptical diamond stylus not a conical ruby type, buy yourself a cheap RIAA pre-amp and digitize the output of that.

[hinekadon]

If you really want to strobe it ?for whatever reason . Lets see any incandescent lamp will do so lets say a 230vac lamp beside the platter um no too fast for our eyes so logic says half wave rectifv the mains and see half of it but you may have to focus it on the platter so use a bit of nylon 50kg fishing line taped to the top of the existing led and put your light in a box with the fishing line poked thru a hole , just sand the ends with 1200 sand paper and it should work ok for you cheers don

[mtv]

Even if the strobe worked, I wouldn't trust the platter markings to be accurate anyway, given the overall quality or the unit.

[loopyloo]

buy yourself a cheap RIAA pre-amp and digitize the output of that.

Like this ?

[hinekadon]

hows that going to work if the platter is to fast or too slow , From what I can see it cant theres no delay line on the audio ?????

[hinekadon]

aLL one has to do is count the markings and ensure they are equal-distant apart so that 50hz can be seen, the diameter doesn't matter for this exercise

[wotnot]

Like this ?

Yeah, that's one option. There's also kits out there for under $20 that you assemble yourself.

Oddly enough, jaycar still carry the pre-amp I used way back when -->> (works very well, 9volt battery lasts forever)

And obviously you can keep throwing money at more and more expensive pre-amps, but with little gains for your intended purpose.

There were a few decent turntables made years ago, with the riaa pre-amp builtin, but it's the exception not the norm -- most of them expect to be plugged into a pre-amp (or amp with builtin pre-amp... once upon a time, some amps had 2 phono input pair... one set for ceramic cartridge, the other for magnetic cartridge). I did read somewhere that it's now possible to capture/record the audio data 'raw' from the turntable, and apply a RIAA filter mask to that in audacity, but I've never tried it (possibly because it's close to heresy, and you'd only get the digital approximation of what is inherently a very analog thing =)

I should echo what fester says -- when it comes to digitizing vinyl records, you really don't want to go applying noise filters or other tricks, as it tends to remove the 'presence' of the cartridge/stylus/tonearm from the sample ; this is why all my vinyl is encoded in flac files. which I can filter/transcode later without need for the original vinyl source again.

Of course, you still need procure a good turntable for a riaa preamp to be of any use to you =)

[coalminer]

why not buy a strobe disc and use your home lighting