Playmaster amp build or not

Hi

My Bro just bought 2 playmaster pro series 3 ( 1994 Electronic Australia Magazine) for cheap $250 , he is beginning to build them with my help, each amp use 2 X 300VA ( 100V center tap ) transformers, and I had in hand 500VA one , is there any advantage using 2 transformer one for each channel over a single one, we need a bit of space inside to put more filter caps and spaker protector. And finally is this kit can provide performance compare with today kit , it is a plastic mosfet based one, anyone know about this kit , it was Jaycar cat KA1760 but discontinued since 2001, orginally we bought them because the cases with intregral heatsink but after look at the article in the kit , it is a high power amp with very little distortion, any one biuld it before , and how it sound ( it would take more than a month to build and we still half/ half ).

Thanks

Now that you have it, why wouldn't you build it?

If you were considering buying, I'd say buy a Behringer A500 for $300 and have a new amp with a warranty without the risk of making a mistake that you may not know how to fix. But you've spent the money, hopefully you're in it for the fun of building more than anything.

Does the kit have separate power regulation stages? one for each channel?

If it does...

Separate power supplies powering separate power regulators, should provide better stereo separation than what a single power supply would do powering separate power regulators.

This is as I understand it with my limited knowledge.

Back in 1996 I built 3 of these from kitsets for my Home Theatre.

These amps are awesome performers for the price, if you build them carefully.

They aren't an easy build, and adjusting the bias is bloody awkward.

Also the chassis is too flimsy to support the weight of the transformers. I used DIN rail underneath the chassis to add support.

You need to build them as designed using both transformers.

Otherwise you might as well buy Bose.

lol bose....................

I purchased my Playmaster 3 power amp from someone who had it professionally built about 12 months ago, I currently use a Benchmark DAC1pre connected directly to the Playmaster power amp. To my ears it sounds a lot better then the Rotel RX-1052 I am currently trying to sell. The Rotel would be considered one of the best 2ch receivers in its price range, the Playmaster however is clearly better. Also note that I own an elektra Reference 2ch amp and 7ch Theatron multi channel amp, also own a class D Belcanto S300 power amp. I originally purchased the playmaster to run a set of 8ohm outdoor speakers but it sounded to good to be only used for this task. I would consider the playmaster to sound similar to the Elektra Theatron but is outclassed by the Elektra Reference and possibly the Belcanto S300 too. For what the Playmaster cost me (around $350 built, purchased secondhand), it was money well spent.

JDH.

Hi

Thank for the replies, that help me made decision to keep it, we bought them cheap $125 each kit, the owner has commented built half way but somehow he could not finish them and sold as a bundle , we thought that we would use the case to house my firstwatt F5, but with the heat sink lengh only 300mm , if it sound similar to Elektra Theatron then I don't want to crap them, tomorow I will begin put them together.

And Yes it has seperate power supply for each channel.

Regards

Does the kit have separate power regulation stages? one for each channel?

From memory the power supply is unregulated and relies on massive transformers, bridge rectifiers, and storage capacitors.

Not necessarily a bad way to go, as it "Keeps It Sweet & Simple".

Only thing I would do if building one at the moment would be to replace the supplied PSU capacitors with better ones.

JDH.

Hi JDH

I would like to upgrade the PS CAPs , but space is limited and at the rating of at least 80V, it is not small, that why I want to use single 500VA instead of 2 X 300VA transformer so I can have some room for speaker protector and CAP upgrdade.Today I asemble the two amp and cases one is complete, one is missing nut and bolts.The reason why I bought them is in the past I built ETI 5000 , bur in 1989 i upgrade it to Pro series one that still ake use Hitachi lateral TO3 metal can Mosfet that sound very good detail and warm, and after I bought these I realize that it now use Plastic TO3P Mosfet , that why I have to ask if anyone build these how it sound before i continue build them or take the cases to use for something else, but after hear the advices in this thread, I made decision to continue building them.

Regards

Regards

Hi,

Prior to building the 3 playmaster pro series 3 amps (see post 4), back in 1984 I too had built an ETI-5000 power amp, and the matching pre-amp.

My listening impressions indicated that the playmaster was the better amp.

My 3 playmasters were used for 11 years with no problems whatsoever, and have since been on-sold to new owners who have had no problems either.

Forget the speaker protection and extra caps. Just build it as per the original design, although I recommend heavier gauge wire, and IEC sockets to allow power cable upgrades later. I didn't bother with the clipping indicators either.

Thanks for these advices, I started last night , all PCB board completed, today or tomorow I have to goto Bunning ware house to buy screws and nuts , and get some heavy duty hook up wire from Jaycar, I wll have pics when completed.But I wonder why all the caps in this amps is very tiny in a rectangular yellow plastic pack, ( compare to the huge ones same value in a valve or in a mod amp ) and all resistors is pretty tiny too , any way I will have to completed them first before my wife clean up the table and all small parts lost .

Regards

Hi,

I built one of these in 96 when I first got to OZ. It is still running my front channels and working fine. As someone else mentioned some better filter capacitors would be a good idea. Mine dried out after about 5 years (sounds BAD). I was just wondering if anyone has a schematic of this amp. I have moved several times and the original schematic has been lost.

Hi

I have the whole assembly instruction here, I will dig out my camera and post schematic here ( don't know legal or not as EA has no more existed ).

Regards

Im running 4 of these, passive biamping Vaf I66's Good amp but as mentioned earlier the Caps provided are rubbish.

Got a few spare modules so im going to build another 4 and look at active triamping and a running 2 into a sub.

Hi

I have the whole assembly instruction here, I will dig out my camera and post schematic here ( don't know legal or not as EA has no more existed ).

Regards

Copyright operates for an utterly obscene SEVENTY FIVE YEARS! Yep. 75 years. The publisher of Superman comics is protected for 3/4 of a century, yet the people who invented the artificial heart, or skin grafts and a whole host of really important stuff, get only 7 years protection.

That said: No one is going to complain.

I've had my pro series 3 for about 7 years or so.

I used it in a tri-amp setup, but I originally used them as a full bandwith stereo amp and it worked and sounded great.. It's still going strong, but has been relegated to my "secondary" system..

That's my 2 cents worth :-)

hmm...If these are the same as the two we have here, the resulting sound can vary a lot depending of who builds them, as we found out the other day.

We have one that or knowledgeable friend built (Leonard) and one purchased off ebay, exact same kit, same parts and the one off ebay sounds very ordinary compared to the one Leonard built, it has a more open, warm and involving sound.....from what I can gather attention to detail is the only difference in build.

Yes Datafone,, that's my experience anyway.. When DIY'ing with soldering/electronics, depending on how it's built goes a long way into how it performs..

Taking time to run extra solder over high current tracks. Changing solder thicknesses used for low/high current tracks. Drilling solder holes a bit wider to allow a heavier gauge wire etc.. I believe all adds up to the end result :-)

Whats the saying?? "Treat every job as a self portrait" (or something along those lines)

FWIW - I have an early Redgum 132 watt integrated amp, it looks like it was based on an earlier Playmaster design – even the PCB appeared to be the same. The components in my Redgum appeared to be sourced from Altronics.

I disassembled my Redgum prior to moving house last year and have never got around to finish fixing it.

Hi

Here is The Schematic

Regards

If anyone is interested, I'm about to sell my Playmaster 3 amp as I've upgraded to a Bel Canto S500 class D power amp.

JDH.

Meganinja,

Thanks for the schematic.