Pioneer A400?

breezmagic71

hello.
Just bought pioneer a400 for my vinyl system, because of shining reviews. Amp is outstanding cosmetic condition, very surprised how people love and keeps things over these years. Look inside through holes of the top and all parts looks as new as they where made yesterday. Until it comes to sound. I was really disappointed after listen for a while just connected amp to phono. Sound was flat and Not involving. Cant say its harsh.  I can compare with my old Nad3020, which i found very natural and soft sound for listen to Vinyls!. So after i connected my NAD as pre amp out to pioneer cd input. Well, that was different, because i still can hear my nad, only bit more power.
So i read more reviews and i don’t understand why this amp being so popular even back in the days. Maybe because most of music was cd’s when this amp comes out for sale.
Dont know what to do with it. Maybe try sale on ebay.

oldcootstereo

Maybe this helps...
Pioneer A-400 amp. What's with the hype?

Timmy C

The fact that it was so popular and well loved should make it easy for you to get your money back on it. If you like the NAD but want bit more power then one of these should come in at less than the price of the Pioneer. I had one many many years ago and although it's too long ago to give any details, I can say that I liked it very much at the time.

NAD 3240PE INTEGRATED AMPLIFIER 80W RMS TAPE LOOP PHONO  | eBay

breezmagic71

Thank you very much for advise.  I don’t  really know best sound for vinyl. Have been trying many amps inc denon, audiolab, marantz and found nad closest to sound for vinyl to listen, no harsh or fatigue, even tryin to connect many different pre amps, but they didn’t change sound drastically, maybe because nad pre already saound good. Anyway, still keep tryin amps and looking for best sound.
Visit t audio and had very wise advise try Primare.
Technics 1200MK2,Nagaoka110,NAD3020,B&W686S2 or MAbronzeBR5.

oldcootstereo

When I started out playing with audio in the late 1960s/early 1970s, there was the same debate, just with different gear. The "establishment" types swore by tube amps and massive JBL/Altec-Lansing type speakers.  Bear in mind, some audiophiles at that time still insisted that 78's were still a credible hifi source, and reel-to-reel tape for home use was a big deal.  

A high-reputation audio contractor actually supplied Voice of the Theater speakers to the new, state-of-the-art Hamilton Place, which opened in 1973.  Despite being based on 1930's tech, the VotTs were a stop-gap because the electronics of the day couldn't deliver on the original "tiny speakers spread through out the seating area" the designer envisioned.  Readers here wouldn't be happy with the VotT sound output after paying to see a movie or concert.
Living Legend: Altec Lansing's ‘Voice of the Theatre’

But as transistor tech improved and speaker tech evolved (in large part due to the NRC/Toole et. al. findings), the old guard stood on the fact that recordings from (and in the style of) the previous decades "sounded better" on the tube/big-bin/horn systems.  Pink Floyd et. al. sounded like confused mush through those systems, and us young'uns flocked to cheaper/smaller, but good price/performance ratio transistor amps and Dynaco-style speakers.  Old-style jazz/symphonic recordings through transistor/small speakers systems tended to sound harsh and flat.  Now the shoe is on the other foot for those "classic" ground-breaking systems, and the compromises made in the still developing transistor/smaller speaker systems to accommodate both old and new recording methods/standards now seem like fatal flaws compared to newer gear.  

So now the move to digital sources and resurgence of vinyl (tape has basically disappeared from home hifi) has opened up old wounds, and the debate begins anew.  

It is no surprise the A400 (especially one still sporting its original capacitors) will suffer against both new/evolving transistor tech and current refined tube tech.  

Vintage audio gear is becoming like vintage cars... it is "good for what it was at the time" and possibly worth preserving/improving, but can't compare to new gear for convenience/performance in day-to-day use.

Steve74

I also have an A-400 and use it connected to a Project phono preamp instead of the Pioneers own preamp and I love the sound from it, much better than several other more expensive and newer amps that I tried ( Marantz KI Sig and Onkyo 3020 to name two) Maybe try it with a separate preamp?

oldcootstereo

@Steve74 Much of what gets interpreted by our ears/brain as the "sound" of a system or particular amp/preamp/etc. is how that system/component creates/handles distortion. All circuits/amps distort to some degree, unless the signal/output is well within the relatively small linear portion of the amp's response, so that the distortion is not noticeable to human ears.  Music particularly presents a spectrum that does not correlate well to "pure" test signals, including pink noise, so the distortion (pleasant or otherwise) produced by the circuit may be apparent to the ear/brain, but not seem significant in "objective" tests.  So amps with nearly identical specs often sound different, which should not be if the tests/specs give a true picture of music reproduction performance.

Early transistor gear generally sounded "harsh" compared to tube amps, as transistor distortion tends to emphasize odd-frequencies and tube amps even-frequencies.  Adding up odd-frequencies is one method of how square waves are generated, so inherently sound harsh.  Even-frequency distortion is less annoying to the ear, so in moderate amounts as found in good tube amps sounds "warmer".  Too much even-frequency distortion destroys definition.

So many "classic" transistor amps like the A400 were designed to limit the amount of odd-frequency distortion which inherently sounded harsh, giving a "warmer" sound to fit into the frequency profile of the available speakers/sources based on designs originally intended to be paired to tube amps.

Then there's the psychoacoustic aspects of how humans hear differences as presented, in your example, when we swap out one amp for another. This has eluded well-regarded researchers since sound reproduction began.  Ever hear an old Edison cylinder player?  (My father owned one in near-pristine condition.) How anyone ever thought they sounded "good", let alone as an accurate reproduction, is testament to humans hearing what they think they hear, not what they actually hear.
Listen to Edison Sound Recordings - Thomas Edison National Historical Park (U.S. National Park Service)

So yes, swapping out the A400 for modern amps will give a different sound, the same as swapping in a transistor amp for a tube amp.  But does that mean the A400 (or tube amp) is "better"? No, it could mean your ears/brain are expecting a particular sound/profile that the A400 produces, and more importantly, that the rest of the system/room has been compensated for at least some of the reproduction peculiarities of the A400.  The modern amps simply have different "peculiarities" to be compensated for (or not).

If you really like the way the A400 sounds in your system/room, why change it?  What is the A400 "missing" that you would like to hear?

Until I got my new gear (Yamaha A-S501, Q Acoustics 3020s, HSU VTF-2 Mk5), I thought my old late-1960s/1990s system sounded pretty good.  And the old stuff was "good", but took a lot of EQ/tone to get to "good" given my switch to digital source.  The new gear now runs with flat digital EQ, tone-section defeated, is fairly well-balanced in the room and continues to reveal subtle content which the artists/engineers deliberately put in the music.  Worth every nickel spent, but as I sequentially bought/installed each new item into the existing system, flaws in the older gear were revealed.  I began by replacing my Kenwood 2002, then the Bose 101s, then the M&K Goliath sub.

Simply swapping a modern amp in place of a "classic" is like changing engines in a car, often would be like dropping a V8 where once was a 4 cylinder.  It may work out well, but there's a lot more to consider than just "will it fit".

breezmagic71

Thank you for this long and comprehensive hi end portrayal Its always very nice to read this kind of descriptions. To be honest im not yet in this kind of level, but we gettin’ there
  As you mentioned, you have now yamaha sa501, this amp i was thinkin before pioneer.
Yes, i try pre amp with my pioneer, i had project tube box s, sold it. has not proved. Main problem i don’t like a 400 sound is bass deficiency. Also sound is flat, uninvolved. Pre amp not much helped. Something missing but i dont know what i need to fix

oldcootstereo

Looking for bass?  Bear in mind your room has as much to say about bass performance as the gear.  

The Steve Hoffman link I provided above speaks about why the A400 may not perform as well in the bass region as other/modern amps.  The "on paper" specs say as low as 5Hz  0/-3db, but without knowing exactly how Pioneer arrived at those numbers, even reviews of the day didn't heap praise the A400's bass performance, especially with some of the the speakers of the day.  

Also remember that separate subwoofers were still considered a new thing in the early 1990s, and few expert audiophiles thought them "necessary" to get good bass.  That bias continues in some circles to this day, along with "hyper-minimal electronics/xover/EQ/tone in the signal path" idealism.  I was an early sub adopter, bought my passive xover M&K Goliath shortly after they were introduced in 1976... they had not released the powered Volkswoofer yet.  Paired with a Crown DC300A (bought used), power was not an issue for driving the Goliath and Bose 101s, and my Hafler preamp handled the inputs quite well.
Crown DC-300 power amplifier  
I also had a Dynaco PAT-4 (originally paired to a Dynaco ST120) mentioned in the article, but my later Hafler preamp was better with the DC300.

The A400 was an "answer" to amps like the Crown DC300 series, which was the grand-daddy of big-power transistor amps , originally designed for use in scientific laboratory applications. Audio use was "off-label".  180w/ch into 4 ohms iirc, even the most powerful audio tube amps were limited to about 75w/ch back then.  But the massive power supply and simple signal path made up somewhat for the slow semiconductors of the day and some of the not-so-great input level niggles that the DC300 inherited by being designed to handle a broad range of lab inputs, not just Line In impedances/voltages and simpler waveforms than music. You couldn't kill a DC300, even with a baseball bat, but you could fry speakers with ease.  The caps in mine finally gave up, and the bill to get a complete rebuild was beyond my budget.  

That said, the reproduction performance I now get from my new gear is light-years better than the best I heard from my own system and from much more expensive systems than mine back in the day. Digital source is a major contributor, as the full signal content is potentially available, the system/room just needs to be matched reasonably well to deliver accurate reproduction to your ears/brain.  

Bass?  The VTF-2 Mk5 literally shakes the floorboards on songs like "You should see me in a crown", "Thunder" and "Stompa".

Costello

I’ve been experimenting and revisiting some old and classic hifi units recently and some units still sound awesome. I’m not going to go into their various merits here: it’s just personal opinion based on my own listening. The biggest issue is of reliability. Many of these classic units simply can’t cope with modern delivery methods and arrive damaged or more damaged than they were. Knobs don’t feel as taught, speaker bindings can be loose, scratches on scratches etc. etc. They also look dated (if that matters).
The classic car analogy is great. My modern Merc has all the bells, whistles and safety features you want. It’s economical, efficient, looks great and (touch wood) never breaks down. But, my goodness, do I miss my 1966 MG. Sure, it broke down more than it worked, but nothing could touch it for a fun driving experience.
Guess it’s all about what you like and want.