A question for the Australians on the forum.
I was in the local Jaycar store picking up some cheap stuff today and got to talking to one of the salespeople there. He also builds speakers and we know each other in passing
He was telling me to buy a discontinued amplifier kit if I really wanted some grunt to drive the new subwoofers I am planning
Studio 350 - High Power Amplifier Kit Back Catalogue | Jaycar Electronics
While I am daunted by the prospect of assembling something this big I am intrigued by the possibility of getting something this powerful cheaply.
It just happens that I have a pair of big toroidals sitting in the shed that I got years ago cheap and I've been sitting on them for a few years waiting to pass them on at a small profit.
But there is little point in building something that doesn't perform or sound good so I am looking for some feedback on the kit.
If the kit itself is good value is it worth buying better components for some sections? If so what components are /would be worth changing over?
I have several old party amplifiers "dead in the shed" which have massive heat sinks I can salvage so the major costs are already gone.
Opinions and help please fellers and fellerettes.
Now that the house renovations are almost finished I am going to need some projects to keep me out of my beloved wifes way and I really don't need to build many more speakers
I was in the local Jaycar store picking up some cheap stuff today and got to talking to one of the salespeople there. He also builds speakers and we know each other in passing
He was telling me to buy a discontinued amplifier kit if I really wanted some grunt to drive the new subwoofers I am planning
Studio 350 - High Power Amplifier Kit Back Catalogue | Jaycar Electronics
While I am daunted by the prospect of assembling something this big I am intrigued by the possibility of getting something this powerful cheaply.
It just happens that I have a pair of big toroidals sitting in the shed that I got years ago cheap and I've been sitting on them for a few years waiting to pass them on at a small profit.
But there is little point in building something that doesn't perform or sound good so I am looking for some feedback on the kit.
If the kit itself is good value is it worth buying better components for some sections? If so what components are /would be worth changing over?
I have several old party amplifiers "dead in the shed" which have massive heat sinks I can salvage so the major costs are already gone.
Opinions and help please fellers and fellerettes.
Now that the house renovations are almost finished I am going to need some projects to keep me out of my beloved wifes way and I really don't need to build many more speakers
Ted,
It's a good circuit with reliability and good sound.
You can fit toroids vertical. It is a good idea to use a couple of 300VAs, one for each channel, and this should be consistent with your two old toroids.
The Studio 350 uses MJL21193/94 outputs, four pairs each channel, and these are very slow. The amp uses heavy global fb, and with the slow outputs this amp would not have a lot of resolution. If you are after grunt, low noise and strong bass, this is your amp; but if you want more resolution and better imaging, faster outputs would be a better option and this would require revising the stability settings and require some expertise.
Hugh
It's a good circuit with reliability and good sound.
You can fit toroids vertical. It is a good idea to use a couple of 300VAs, one for each channel, and this should be consistent with your two old toroids.
The Studio 350 uses MJL21193/94 outputs, four pairs each channel, and these are very slow. The amp uses heavy global fb, and with the slow outputs this amp would not have a lot of resolution. If you are after grunt, low noise and strong bass, this is your amp; but if you want more resolution and better imaging, faster outputs would be a better option and this would require revising the stability settings and require some expertise.
Hugh
Thanx AKSA
It was recommended as a subwoofer amp so I assume that slow is OK in terms of resolution there.
As for the transformers? I only have the bigger units but 50 + 50 @ 500VA is what they blurb calls for and to keep cost down I'd like to use what I have in the shed. Big heat sinks seem to be getting very expensive
It was recommended as a subwoofer amp so I assume that slow is OK in terms of resolution there.
As for the transformers? I only have the bigger units but 50 + 50 @ 500VA is what they blurb calls for and to keep cost down I'd like to use what I have in the shed. Big heat sinks seem to be getting very expensive
A Saroya would be wasted on my leaded ears and the others wasted as a subwoofer amp.
But happy days the Geelong store had 2 of the ultra-cheap chip amp kits for $40- the pair So I got them.
I may have to make the next system quad-amped to use them tho.
My old Inkel Subwoofer amp is getting old and I was simply looking for a cheap replacement, something about those old double die Panasonic transistors sounding good with my old fashioned speakers
I would like a project [ the easier the better] to use those huge trannies in tho
Hi Moondog,
have a look at this link:
Roman Black's gainclone amp
may give you some ideas for better performance.
Cheers
P.S. i think you asked about a LM3876 chip amp kit, but now it looks different...
have a look at this link:
Roman Black's gainclone amp
may give you some ideas for better performance.
Cheers
P.S. i think you asked about a LM3876 chip amp kit, but now it looks different...
Stanialav I think the moderators merged two questions but lost a post somewhere.
< My question about the chip amps was regarding the cheaper small parts that come with the Jaycar kit. The Jaycar kit was only a dollar more than the amplifier chip on its own.
I made one of these kits up about a decade ago and is was only just OK but I think I shorted myself by using a heat sink that was too small and ditto on the power supply
But honestly I don't need a huge amount of power to drive the tops of my computer system and I am wondering about the wisdom of buying another 160VA 25+25V toroid and thinking about sharing the toroid with both chips.
I'd actually be more than happy with 20/25 watts per channel to drive tweeters or small computer tops
< My question about the chip amps was regarding the cheaper small parts that come with the Jaycar kit. The Jaycar kit was only a dollar more than the amplifier chip on its own.
I made one of these kits up about a decade ago and is was only just OK but I think I shorted myself by using a heat sink that was too small and ditto on the power supply
But honestly I don't need a huge amount of power to drive the tops of my computer system and I am wondering about the wisdom of buying another 160VA 25+25V toroid and thinking about sharing the toroid with both chips.
I'd actually be more than happy with 20/25 watts per channel to drive tweeters or small computer tops
The amp is originally a build from elektor magazine.. I think you can find the article online.. studio350 amplifier.. I haven't heard the amp but I'm sure it's better than moondog describes.. yes mjl21193/94 are not the fastest outputs but can deliver pure HiFi.. some day I will build this amp too, cause I'm sure it sounds really good.. you can upgrade to mjl1302a mjl3281a newer and faster outputs.. maybe match the input ltp yourself.
A single 160W toroid will be sufficient for 2 channels.
Follow Roman Black's advice and you'll get it as good as it is possible.
Especially regarding the regulated PSU.
Same with the main board itself, beef up the caps on it and change that 22k input resistor to something like 100 - 150k.
Lower PSU voltage, 25 - 28V (after a regulator) will give you much better performance with difficult or low impedance loads.
Last thing you can do is replace LM3876 with LM3886, but I guess you don't want to buy another IC.
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