Have You Listened to a Low Power Amplifier?

dcmeigs

mhardy6647 wrote: »

do you have a shot of its innards?

I don't have one at hand. That one is like me if I remember, in that it looks best with it's shirt on. There is a little corrosion on the chassis that has worked through the plating as I recall.

The real issue is that the mono FM circuit works just fine but when you switch to FM stereo, it doesn't sound right. It's a problem with the multiplex circuit I imagine. I bought a nice vintage Simpson signal generator to work on it but as luck would have it only the 400 Hz audio oscillator works. I need to tear into it and get the RF oscillator working but I haven't had time. Perhaps later today:biggrin:

Are you any good with RF circuits?

mhardy6647

I live in fear of DIY tuner alignment :-)
Back to our regularly scheduled topic...

dcmeigs

mhardy6647 wrote: »

I live in fear of DIY tuner alignment :-)

That would make a good signature quote.

The old guys say that FM stands for "Fu[!in' Magic". I have a very low success rate with tuners. But I'm willing to change, if I have to, I guess.

dcmeigs

Wards web. I remain mesmerized by your DIY Bottlehead amp. How did you manage to disappear the laminations in the PT? They appear smooth. Did you fill with polyester resin or wrap them? How about the OTs; did you remove the metal frame and spray?

zingo

Here is his website with pictures of everything. Crazy good work and attention to detail; some of the best I've seen.

zingo

zingo wrote: »

Here is his website with pictures of everything. Crazy good work and attention to detail; some of the best I've seen.

http://www.wardsweb.org/audio/index_audio.html

DMara

Lately I've been slowly but surely setting an office audio rig up. Here's my little experience on a Low Power Amp:

* Amp: Audioengine N22 (http://audioengineusa.com/Store/Audioengine-N22) --- bought brand new from the Audioengine website
* Speakers: Audioengine AP4 --- bought from markmarc
* Sub: Polk Audio PSW10 --- picked up from fossy for a nephew, but now got back to me since he finished his college
* Cables: PS Audio xStream Prelude Speaker Cables - PS Audio xStream Reference IC (for DAC) - SignalCable Analog Two IC (for sub) --- bought from zingo & Conradicles
* DAC: awaiting the arrival of a Kingwa NFB-3, temporarily using a Lexicon Alpha
* Wireless adapter: Audioengine AW2 (for iPod Touch wireless music output)


Loudness: the Audioengine N22, rated at 22wpc, is extremely powerful. Turning its knob just about 1/4 of the way is already more than enough to provide ample sound for a small 12x12 room. I'm even afraid of turning it up more since the window is right behind one of the speakers :biggrin: Reading online reviews, it sure sounds like this little amp can even deliver quality power to plenty of floor-standing speakers.

Sound quality: even with a mediocre DAC such as my Lexicon Alpha, a below average sub such as my Polk Audio PSW10, sound output has been very pleasant to the ear, with high clarity and glowing smoothness, and harshness or brightness due to over/under powering was nowhere to be found. Voices from some of the hi-res FLAC files such as ones from Andrea Bocelli's Vivere album seemed a little bit flat comparing to listening in my 2-channel bedroom set via the Denon AVR-4810ci built-in DAC, Emotiva XPA-2 amp, and Polk Audio LSi15 speakers. However I blamed it on that temporary-utilized Lexicon Alpha DAC. I hope the being-shipped Kingwa NFB-3 DAC will fix this issue, cross my fingers. One thing for sure: the sound quality from the combination of Audioengine N22 amp - AP4 speakers - AW2 wireless adapter made music coming out of my 4th-gen iPod Touch quite lively, and that's an understatement! It was actually so pleasing listening to music from the iPod Touch that way that I had some doubt it came through the feeble iPod built-in DAC, that plugging the AW2 wireless receiver to the Audioengine N22 amp and wireless sender to the iPod Touch actually bypassed the iPod DAC and reached a better invisible DAC somewhere inside either the AW2 devices or the N22 amps :biggrin: Of course that wasn't true, and I got to praise the Audioengine N22 - AP4 - AW2 combination for this

In short, the 22wpc Audioengine N22 is an amazing amp, I couldn't fathom how such a little device provided such powerful and quality sound output. It really convinced me to change my mind on how to value the specs of an amp. However, I still have doubt that a Low Power Amp could drive a set of 4Ω speakers in a bigger room, especially for HT purpose. In the near future I plan to bring my little Audioengine N22 out of its office environment to test it in my bedroom 2-channel and my living room 5.1-channel setup for further proof, allowing it to drive Polk Audio LSi15 speakers to compare it to my other 2 amps, the Emotiva XPA-5 for HT mode and XPA-2 for 2-channel mode.

MarkTX

Dared MP-7 integrated 7wpc stock chinese tubes into some martin logan odysseys. Didn't try hooking it up to my power hungry magnepan 3.6's or SRT's.

acchen

Low power tubes are yummy.

mantis

http://www.nilesaudio.com/product_amp.php?prodID=SI-1230&recordID=Multichannel%20Power%20Amplifiers&categoryID=System%20Integration%20Amplifiers&catcdID=4&prdcdID=FG00737

This amp rocks the house and has nice dynamic range to drive 8 ohm load speakers.

mhardy6647

Playing with this cheap and cheerful little amplifier (PP 11BM8 for nominally 8 wpc - probably more like about 5 wpc at reasonable distortion) on the 604Es today. It is dead quiet, and sounds far better than it has a right to.



The one above was built from the kit from www.tubesandmore.com Review of the virtually identical version marketed by S-5 Electronics (using 11MS8) here:
www.audioxpress.com/reviews/media/1102hansen2145.pdf