Solid-State Power Amp Adventures

@Marvey are there any power requirements you're looking to meet for this search? I was just thinking of the old (and still in production) Monarchy power amps that used to intrigue me. I've never had a chance to hear them, but I couldn't help but be curious since they were relatively cheap for class A amps. I think they're like $1179 for the stereo amp or each mono amp, but just under $1000 each when buying direct 2 at a time. The monos put out 100 into 8 ohms and the stereo amp does only 25 watts (hence the initial power requirement question). I believe the stereo amp can push 80wpc when bridged and operates balanced while the monos are only single ended (even the xlr).

 

not surprised that the hegel was the better amp. in all honesty, the other amps are rubbish.

 

anathema?

I've always wondered what all the fuss about these is about.

And, if no DIY, what about the Clones monoblocks? (Also wonder what @tomchr would say about Clones vs. his chip amp with regards to implementation).

 

I'm curious how the Emotiva BASX A-300 compares to the amps you've tested. At $399, it's certainly affordable. On the surface, it seems similar to the upcoming Vidar: both are class AB, both have linear power supplies, the Emotiva may actually be a bit more powerful than what I last saw Jason reporting for a Vidar prototype, but they're in the same ballpark in terms of power.

Jason made it a point to not require fans to cool the Vidar, whereas the A-300 has a smaller heatsink with a pair of fans to cool it.

I have no idea what kinds of compromises may have been made in the A-300 in terms of the signal path, so that they could sell it for $399. Is the BASX A-300 better than the Parasound A23? I doubt that Jason made many compromises with regards to sound quality on the Vidar.

Another power amp I would love to hear a bit more about would be the Van Alstine 400R, 600R or their precursors. Yeah, I know they're 4-5x the price of a Vidar, and this is a solid state power amp thread, but if someone had one that they would lend to Marvey to test, I would be interested in the results.

 

He has plenty to say on his neurochrome page. In fact he has 2 lm3886 implementations. One that is closer to the data sheet application notes, the other is his ultra low distortion build with opamps galore.

I made an lm1875 gainclone myself which powers my TABAQ. I use a Magni 2 uber as a preamp and it sounds great. At 20W/ch it doesn't need a lot of heat sinking and can be made into a compact amp to match a Fulla 2.

As much as I like chipamps though they are limited it power. I think the best application for them is in powered or active speakers where space is limited.

 

Have you tried gear from Naim or Marantz?

 

Not sure if anyone has thrown Rogue Audio out as an option, i have been very impressed by the sphinx

http://www.rogueaudio.com/Products_sphinx.htm

I don't own it, i auditioned it with a friend who chose to buy it and i get to hear it now & again.

..dB

 

First thought: Definitely not enough heat sinking. The clones may be adequate for easy listening, but if you push them to 30-40 W into 4 Ω for any length of time they'll very likely overheat. I'd expect them to get rather toasty even with music at moderate listening levels.

The basic LM3886 is a pretty decent amp if you take proper care of it (i.e. follow all the recommendations in the data sheet, including the application section). Sadly many don't. The end result range from amps that provide mediocre performance to amps that oscillate under certain load conditions. This has given chipamps and the LM3886 a bad reputation in some circles, which is unfortunate as it's actually a capable amp in the right hands. I aimed to right this by providing the LM3886 Done Right, which provides performance slightly better than the LM3886 data sheet indicates.

The Modulus-86 and -286 take it up a notch by applying error correction to the LM3886. That combined with the layout techniques used is why the Modulus-86 and -286 provide world class performance. The only commercial product I've come across that meets the performance of the MOD86/286 is the Benchmark ABH-2, which last I checked would set you back a cool $4k. A stereo Modulus-86 can be built for $400, including the chassis.

Tom

 

Well, it fits the SS bill as well as the Vincent 331 will (though I'm not sure on whether or not integrated amps are welcome). It's also almost right on target for price at just under $1300, so a small sale, and open box unit, or a used one would definitely come under $1200.

I've only heard it at a show and got to talk to Mark for a bit about it and just general philosophies on the industry. It sounded decent there, but conditions weren't great, so it wasn't really the best environment to look for "warts". Not that my opinion particularly weighty, but it seemed like a product that could benefit from a closer look.

That being said, it's not really on my list as I've got a personal preference for separates.

 

I would be very interested to hear how the @tomchr designs compare to the Hegel especially considering your speaker setup requires so little power. While i am well aware these products are in wildly different price brackets & the Mod286 would require chassis tooling that i do not have the tools or skills to do, it would be interesting nonetheless.

 

How would you describe your listening room? If it's not particularly large, then 25-35 sounds like a good minimum range for wattage. My long term staples have been various Dynaco ST-70s in various modded/unmodded forms, and they do a pretty good job with 35 watts in small to medium sized listening rooms (up to a medium-large bedroom or ~ average living room). Tube amps are of course a different animal, but it seems like something along the lines of a cheaper version of the First Watt F6 would be competent with medium efficiency speakers in that same type of room.

 

maggies are pretty easy load. any amp with good reserve into a 4ohm nominal load will pretty much ride those with ease. only thing going for most maggies is the lower end of spl spectrum being on the low sensitive side making them seem like they're hard to drive but, are not. other than that, they're very easy load on pretty much any amp. have harder time driving infinity speakers with the emit tweeters and walkin's woofers(if i spelled it correctly).

i always test out heavy subwoofer loads personally for stability personally. if my amp can run 1 ohm nominal reactive subwoofer 20hz load and not not kick into protection or catch on fire then it passed my test with flying colors. regular speaker use i don't give much attention into it load wise unless i know my main speakers are gonna be a difficult load at all. most main speakers are pretty easy reactive loads and most speakers out there are. Thiel is known to have some pretty hard load but, that's due to most thiel speakers swearing by 2nd order crossover slopes and always having phase issues making it harder on the amp in question.

i don't know why finding a heavy load is important since i doubt the vidar or hegal is listed for anything under a 4ohm nominal load in stereo. i don't think schiit is trying to run dead shorts all day long like someone like crown or qsc does on a daily basis. unless plan on burning up the amp and testing it beyond or testing how good the protection circuits are i wouldn't worry bout finding a heavy load for it. something even like super sensitive pair of well built altecs with a great analog active crossover would be sensitive and revealing enough of the source content.

 

Adding a "measured" quantifier in front would be enough. I.e., "performance" -> "measured performance"

Performance here typically means subjectively perceived performance.

 

I've heard the 3.7i's already and they were the speakers I thought I was getting. I heard them at the La Habra dealer and those things were gutless. I'm so glad I demoed them beforehand or it would have been such a regretful purchase.

 

I was gonna say this thread probably needs a refresher of the numerous solid state speaker amps you went through!