Class A recommendations

RoadTripper · « **on:** 17 Jul 2016, 12:07 am »

Now that I have a cheap and cheerful pre-amp, I would love to see right here a list of cheap and cheerful Class A amps. Ideally, non-kit offerings.

JLM · « **Reply #1 on:** 17 Jul 2016, 11:12 am »

Saw/listened to a pair of compact 6 watt class A mono-blocks yesterday at a swap meet that sold for $238/pair, but as DIY kits. If you're interested I'll try to get the brand for you. Heard them on very ordinary 90 dB/w/m speakers outdoors so can't comment on the sound but seemed to play loud enough.

maty · « **Reply #2 on:** 17 Jul 2016, 11:33 am »

Maybe

24W×2 Pure Class A Power Amplifier Audio HiFi Stereo amp HD1969 improved version

-> http://www.ebay.com/itm/24W-2-Pure-Class-A-Power-Amplifier-Audio-HiFi-Stereo-amp-HD1969-improved-version-/281808505948

poseidonsvoice · « **Reply #3 on:** 17 Jul 2016, 01:03 pm »

Maty,

That's a John Linsey Hood amplifier from 1969, popularly known as JLH1969. I recognize the schematic on the Fleabay webpage. Along with some of the technical problems with the circuit, large DC input and output capacitors, woefully mediocre sounding Alps pot, poor PSRR, and dubious authenticity of the Chinese sourced parts, it probably sounds decent

Nelson Pass did a wonderful article on the amp design (which was excellent at the time), along with several revisions both published by JLH, Pass and others in 1996, 2000, and beyond: http://6moons.com/industryfeatures/zen/plh.pdf

What can I say? Regarding Fleabay, caveat emptor, you get what you pay for.

Best,
Anand.

rajacat · « **Reply #4 on:** 17 Jul 2016, 01:57 pm »

AMP CAMP AMP KIT
Its a kit but a very simple one. I doubt you'll find better for $269.

Designed by an Audio Legend - Nelson Pass There's also an active Amp Camp forum to help with assembly and mods.

http://cdn.shopify.com/s/files/1/1006/5046/products/ampkitwhite-4k-square_1024x1024.jpg?v=1467161189 [/img]

poseidonsvoice · « **Reply #5 on:** 17 Jul 2016, 02:07 pm »

Excellent recommendation, rajacat! You can probably find someone to build it for you, and used ones occasionally pop up as well...especially if the OP wants a Class A amplifier for pennies on the dollar.

Best,
Anand.

maty · « **Reply #6 on:** 17 Jul 2016, 05:54 pm »

The problem is he do not like a DIY like the Amp Camp Amp.

In 2016 I think that is not very good idea a class A amp.

First One v1.4 with MOSFET, very high slew rate and bandwith or a good class D with good buffer amp are the best options I think. But they are not cheap.

Or a good second hand amp with cheap tweaks (my choice to my second equipment, with the PC).

SH class A: NAD C300

-> http://www.hifiengine.com/manual_library/nad/c300.shtml

-> http://www.audioreview.com/cat/amplification/integrated-amplifiers/nad/c-300/prd_125356_2717crx.aspx

-> http://www.hifishark.com/search?q=NAD+C300

-> -> http://www.ebay.com/itm/142030414943?rmvSB=true

BIG photo (inside) -> http://cdn.head-fi.org/9/95/95abfb58_c05aa11d5663d95f.jpg

With new and better electrolytics (105ºC), a Schaffner RFI/EMI filter (inside or outside with a cable),...

poseidonsvoice · « **Reply #7 on:** 17 Jul 2016, 06:04 pm »

Maty,
We know he doesn't want to DIY, read my post and rajacat's post again please.

FirstOne v1.4 is a great amp, it is also DIY and it is not pure Class A, it is Class AB design and will cost some $$$ to build well. There are loads of other Class AB designs on DIYAudio...and costs can vary wildly on each design.

A used NADC300 is an interesting choice but I have no idea about the design without a schematic and measurements. You are probably more familiar with it...

Best,
Anand.

Tomy2Tone · « **Reply #8 on:** 17 Jul 2016, 06:08 pm »

Quote from: rajacat on 17 Jul 2016, 01:57 pm

AMP CAMP AMP KIT
Its a kit but a very simple one. I doubt you'll find better for $269. Designed by an Audio Legend - Nelson Pass There's also an active Amp Camp forum to help with assembly and mods.

http://cdn.shopify.com/s/files/1/1006/5046/products/ampkitwhite-4k-square_1024x1024.jpg?v=1467161189 [/img]

That's great!

I'm tempted to try it just for the fun of it.

rajacat · « **Reply #9 on:** 17 Jul 2016, 06:16 pm »

Quote from: maty on 17 Jul 2016, 05:54 pm

The problem is he do not like a DIY like the Amp Camp Amp.

In 2016 I think that is not very good idea a class A amp.

First One v1.4 with MOSFET, very high slew rate and bandwith or a good class D with good buffer amp are the best options I think. But they are not cheap.

Or a good second hand amp with cheap tweaks (my choice to my second equipment, with the PC).

SH class A: NAD C300

The OP said, "Ideally, non-kit offerings.
At least with Pass you know you're getting a very competent amp with all new parts , unlike the used market where you don't really know the actual condition until it's delivered. Also there are the Pass forums which are a great source.

poseidonsvoice · « **Reply #10 on:** 17 Jul 2016, 06:19 pm »

Quote from: rajacat on 17 Jul 2016, 06:16 pm

The OP said, "Ideally, non-kit offerings.
At least with Pass you know you're getting a very competent amp with all new parts , unlike the used market where you don't really know the actual condition until it's delivered. Also they're the Pass forums which are a great source.

Exactly.

For others who are interested, here is Pass' write up: http://www.firstwatt.com/pdf/art_amp_camp_1.pdf

Best,
Anand.

Tomy2Tone · « **Reply #11 on:** 17 Jul 2016, 06:38 pm »

There was this one time, at Amp Camp...

Sorry I couldn't resist. Thanks for the links guys! Good luck to the OP.

maty · « **Reply #12 on:** 17 Jul 2016, 06:47 pm »

More about NAD C300

-> http://fjb.m.kaskus.co.id/product/535cba506e07e75b088b48b0/amplifier-nad-c300-integrated

-> [Spanish] http://www.auriculares.org/foro/index.php/topic,6246.msg75154.html#msg75154

BIG photo (inside) -> http://cdn.head-fi.org/9/95/95abfb58_c05aa11d5663d95f.jpg

mlundy57 · « **Reply #13 on:** 17 Jul 2016, 08:40 pm »

Quote from: rajacat on 17 Jul 2016, 01:57 pm

AMP CAMP AMP KIT
Its a kit but a very simple one. I doubt you'll find better for $269. Designed by an Audio Legend - Nelson Pass There's also an active Amp Camp forum to help with assembly and mods.

http://cdn.shopify.com/s/files/1/1006/5046/products/ampkitwhite-4k-square_1024x1024.jpg?v=1467161189 [/img]

Where can you get one of these kits?

Mike

maty · « **Reply #14 on:** 17 Jul 2016, 08:58 pm »

-> http://diyaudiostore.com/collections/kits/products/amp-camp-amp-kit

mlundy57 · « **Reply #15 on:** 17 Jul 2016, 09:18 pm »

Quote from: maty on 17 Jul 2016, 08:58 pm

-> http://diyaudiostore.com/collections/kits/products/amp-camp-amp-kit

Thanks

Mike

ACHiPo · « **Reply #16 on:** 17 Jul 2016, 09:41 pm »

Quote from: Tomy2Tone on 17 Jul 2016, 06:38 pm

There was this one time, at Amp Camp...

Sorry I couldn't resist. Thanks for the links guys! Good luck to the OP.

RoadTripper · « **Reply #17 on:** 17 Jul 2016, 10:47 pm »

FWIW, I know all about the ACA. It also might be a bit underpowered for my VMPS RM40s.

JLM · « **Reply #18 on:** 18 Jul 2016, 12:31 am »

Quote from: Seminarian on 17 Jul 2016, 10:47 pm

FWIW, I know all about the ACA. It also might be a bit underpowered for my VMPS RM40s.

What is the recommended wattage for RM40s? I'm guessing at least 100 watts per channel.

In that case a well synergized Cheap and Cheerful (say $400 for two channels) Class A power amp for VMPS RM40s is not realistic. And would generate a lot of heat.

Folsom · « **Reply #19 on:** 18 Jul 2016, 12:37 am »

They're 89/db.