Old Amps that can still Kick Butt

Not being a believer that time necessarily = progress, I would like to offer the following example of a sonic gem that has transcended time and can totally kick butt in a modern milieu:

The Robertson 4010. I got one of these about two years ago because it was in immaculate condition, the price was so low and I was inquisitive. I hooked it up and let it warm up for a couple of days. OMG this thing was in the super amp league: Transparency to die for, slam that you couldn‘t‘ believe for for a 50W amp.. Peter Moncrieffe wasn‘t wrong in his review of this amp: this thing is in the Sterreophile Class A component category hands down. Even after all these years.

What amps have you encountered that have defied time and can still kick butt today?

I have a Robertson 4010 in my collection. I will have to get it out and hook it up in place of the Sumo Andromeda powering the DCM Time Windows (a formidable combination!).
For difficult speaker loads I have a Perreaux 2150B. 340/680/920 wpc @8/4/2 ohms! This amp is sonically competitive with any of today's four and five figure amps! Typically can be found for $900!
The James Bongiorno-designed Sumo Andromeda (200 wpc) is another great amp from the past! 
There are still lots of Dynaco ST-70 and ST-120s in service.  Many with rebuilt driver boards.  I ran a pair of slightly enhanced Dyna 70s for over 25 years, then added the VTA boards.  One was built by the factory in 1961, the other built by my uncle as a kit in 1964.  They still make me listen and smile.  
My Mac 240 of course. But the "the one that got away" for me will always be the Threshold 400A i sold to buy an engagement ring. Worst decision of my HiFi life hands down. I will never make that mistake again...
Mac 2105. Smooth with a lot of weight and authority. There's a reason why they sell for ridiculous prices, although I think the prices are too high.
One way of saying it:

The list is endless.
New in the amplifier world is no where near being better in all cases.

Circuit refinements are rare, and the effect on sonic end points that the given amplifier circuitry that is new can deliver -- is highly debatable at best. One can point their finger at multiple (probably hundreds) designs that are touted as new, but are really just refinements of an old circuit design that has been around in the given company for 20 plus years. Where they dole it out by the inch as that is all that can be done to make manufacturing work. Where not all sages and mages in audio work with the same intelligence or speed of mind (and results) and such. Where they can, even if the individual is faster and better than the next, they can only work within the market in the way that the market (buyers) themselves - evolve and grow.

Refining or intelligently rebuilding and re-executing an old design (old amplifier) is most times a better path financial outlay and speed of motion toward the peaks-- than buying a new item. It’s not about spending more but spending intelligently.

It is called the last step in audiophile evolution. Where the searcher and the goal begin to become as one. Which is why it can take so long for some to inch their way toward it. Most never get there. I’m the opposite (happened over time), I’ve gone so far as to be taking $10-20k items apart into a big pile of parts within one day of owning them. So I’ve learned to not buy new in the search for audio nirvana. Too costly, by far. I’ve learned to simply buy frameworks and starting points.

This thing where the modketeer or highly talented technician or ’frustrated designer’ is the best person on the planet to know, if one is looking for audio nirvana. Finding one of those is like finding water in an endless desert. Since it is so rare (finding the right one), few people know a real one when they meet them.

Although many an audio company owner and designer is exactly that, but all with different levels of talent and experience, where they are mostly forced to abandon that path (if they started with it), for the path of development of product for retail sale and that associated world of enforced direction, design, and rigidity...

It’s the edge of the whisper of the Buddhist heights of audio listening evolution that you are catching a glimpse of. You’re just touching the edges of it.

But this is a limited hangout, in pretty well all ways possible, even though it is the actual end point. It’s the nature of how things work. All the new (minimum sales levels required) turning into used (so peaks can be reached) is the only way this can happen. The masses must exist so the search for perfection has lands to walk though and experiences to shape it -- on in it’s meandering path.
Circuit refinements are rare, and the effect on sonic end points that the given amplifier circuitry that is new can deliver -- is highly debatable at best.
This statement is incorrect.

The thing that's been plaguing amplifier design for the last 60-70 years is distortion caused by feedback- due to limitations in circuit design that limits how much feedback can be applied. There are things that have happened in the last 20-25 years that have dealt that problem a serious blow! Insufficient feedback is why amps get harsh when you crank up the volume. This problem is literally why tube amps are still being made.
I have an old Adcom 535L that still does a decent job. It's a mid-fi amp for sure and doesn't kick butt out of it's class, but I got it in 1993 and it still works well and really brings speakers to life. Used, it's worth maybe $200, tops, and there's no reason to part with it. (And 
Has the OP ever had anything but older, vintage gear in his rig? What is the context of the comment in regard to performance? What amps have been directly compared to arrive at such a proud conclusion? Just curious!  :) 

This certainly has not been my experience. Starting in about 1980 when I took out my first loan to buy the then new revolutionary Pass designed Threshold 500. Then 20 years later after auditioning many amps and bought a Pass x350, which in every respect bested the Threshold (jaw droppingly so), and the switching over to an Audio Research Reference 160s. In each case the previous generation definitely could not kick butt in comparison to the new one... each generation has had much higher current... the butt kicking part). There would never be going back and a bit of nostalgia. Each generation has absolutely trounced the previous. Also, I think accounting for the time value of money, the investment I made in each amp was probably roughly the same.


If the is a place you could feel an amp held up over time would be in a tube amp, where there was a certain sweetness (not accuracy) that was particularly appealing. Or if you are not actually appreciating better more accurate performance. Over the last fifty years solid state more closely approached the positive attributes of tube gear and tube gear more closely approached the position attributes of solid state gear, converging on best possible sound... as refinements in material science and component construction and selection will continue. I suppose the state of the art will level out at some point, but it sure has not yet.


I guess it is great that some people feel this way. This is how I got the same price in trade in as I paid for my Pass x350 16 years earlier. I got a ridiculous amount of money back for my Threshold as well, on a sound / dollar basis.
What @atmasphere said, +1.         I would add: there have also been major improvements in the materials and manufacturing of rectifiers, resistors and capacitors, since the late Eighties.
A lot of those old amps had (now obsolete) low noise high bandwidth Toshiba and Motorola transistors which are not easily matched with today's offering. The unavailability of those parts is the main reason why amp manufacturers refuse to work on thirty year old equipment. So an argument can be made that some of the old stuff were better than today's, but not as a general statement.
I'm still running a Creek 4140 integrated in my system. I thought it would be easy to get something that sounds better given that it only cost $550 in 1989, but that has not been the case. I think the reason it sounds good from the perspective of timing and ability to convey tonal color is its simple circuit design. I've been lucky not to need a lot of power and I've found that more powerful amplifiers often sound off in timing and veiled to me. Recent amplifiers I've listened to in my system are:

  • PS Audio Stellar Strata integrated (class D): SQ feels artificial. Timing sounds off.
  • Creek Evo 50: Sounds slow. Timing is off.
  • Pathos Classic One: sound quality as well as the quality of the sound seems very close to the Creek. It's a bit smoother, but this difference was rendered moot by getting a new, smoother sounding DAC

There have been some amps that have sounded good to me. I think the common factor for most of what sounds good to me is simple circuit design. I think this simplicity helps in maintaining correct timing in music as well as ability to sound transparent and convey tonal color.

  • The Sugden A21SE sounded quite good indeed. With its Class A design, I think it also has a simple circuit design.
  • I've also got high hopes for a Belles Aria Integrated to sound better than my Creek. I was going to get one to try out, but a friend beat me to it. So I get to try it out in my system for free! The Belles also has a similar design philosophy of simplicity that seems to work well for my listening preferences.
I've been playing  with some vintage Sansui professional series ( BA 2000, CA 2000) pre-power for a year or so as a hobby, and i have to say after a re-cap,etc they are surprisingly nice sounding. Better then the Schiit Aegir in bass, midrange detail and decay only place the new stuff is maybe better is high end extension but that's debatable. so I'd say if you find a quality item form the vintage period it potentially can be stellar if updated-recapped as necessary etc. The key to most vintage stuff I've come across is the fact its aging and if not addressed they are most likely not close to original spec as parts drift with age. once in spec much of the stuff can be quite good. specially the tube gear if it had good transformers to start with. of course your mileage may very and its obviously dependent on what vintage item your looking at, as like today not all gear is worth looking at. 
My NIKKO Alpha 440 is hard to part with. I’m looking for someone who appreciates older ss gear and has the patience to recap it, and extend its life another 40 years. It has performed admirably since I got it in 1980.
The parasound hca 3500 i have owned it for twenty five years and have never heard or found a better overall amplifier for all speakers. My favorite tube amp is the sonic frontiers for the same reason of i have never found a better one to drive tube friendly speaker and i have owned that one for twenty five years. And for integrated amplifiers my accuphase is definitely the best i have ever had by a long shot.
Several amps come to mind when I think of old amps that still kick butt.  ARC D76 with all the final mods.  VERY NICE.  ARC D79 with all the final mods.  Even better with very good dynamics. These are classic tube designs with a lot of attention paid to details.  They needed regular adjustment to get optimal performance.  The D76 was a great companion to many of the early large speaker systems from Altec, JBL and Bozak.  The D79 was just a great all round amp.  Anything could drive these amps, but the ARC SP-6B seemed the best choice of the day.

ARC D110 (solid state).  Excellent in its day and punchy.  A great companion amp for the larger Fulton systems and speakers with wide impedance swings in the LF..  

And just to add to the mix, a McIntosh 275.  Never really my fav, but a lot of people swore by it.  
Maybe not 'vintage' but I still like the way my Madrigal Proceed HPA2 drives my similar era Aerial Acoustic 7B towers. They need a lot of horsepower and the Proceed seems to deliver.

But my breadth of experience is....narrow.

Regardless, I feel no impulse or need to upgrade. Even if I could afford to.
 I also have a Perreaux 2150B, love it. It was the only amp I have owned that my AR9s wouldn't eat. Plus as a dual burner stove, I can make an egg sandwich while listening to Triumvirat at the same time.
Any older krell. I love my first gen ksa-100. Had the electrolytics replaced and it’s good for another 30yrs.. 80lbs, dual mono, pure class A. There are very few amps I’d upgrade to and those will cost a small fortune. 
Pioneer SPEC-4 I purchased in the early 80’s. Last year, I gave it and my beloved DCM TimeWindow 3 speakers, and some other gear to my son.

McIntosh MC2600 I purchased in the late 90’s.  Been sitting unused for about 2 years.  Probably time to sell it and the rest of my Mc components.  
amplifiers have definitely "aged" better than just about any other audio component. I still have a Bryston 4B-ST and a Krell KAV-250a that both sound pretty good. Neither were particularly high-end in their day, but compared to modern amps at their original price point, they hold their own pretty well.
Had to respond after reading n80’s post. My Proceed (Levinson designed) HPA2 powers a pair of Aerial Acoustics Model 8b’s. Same amp, same speaker manufacturer as n80. I upgraded my pre-amp to an Ayre Acoustics K-5e, but did not hear a benefit to upgrading to an Ayre amp at that time. I suspect there may be “better” amps out there, but component matching is part of the reason people keep older equipment. When you are happy with the sound of your gear, you are less likely to seek an upgrade. I’ve listened to a lot of supposedly better newer speakers by firms like Wilson, B&W, Magico and others, but just as I’ve kept my amp (had it repaired at reasonable cost twice), I’ve also kept my speakers. 

Hafler DH-500s were great amps once their front-end boards were modified.  The biggest problem with the DH-500s was the variable speed cooling fan.  It would always kick on during the quiet passages AFTER the big crescendo.  

Like the DH-500, the DH-110 was a solid amp once the driver boards were modified and beefier power supplies replaced the stock ones.  But stock units were so-so.
Any older krell. I love my first gen ksa-100. Had the electrolytics replaced and it’s good for another 30yrs.. 80lbs, dual mono, pure class A. There are very few amps I’d upgrade to and those will cost a small fortune.
Yeah the KSA-50 was really something
The Soundcraftsmen MA5002. Class H beast runs cool, powers any speaker and sounds sweet. Matched with the SP4002 preamp was for me unbelievable fun in the 80s. I have 4 of each. Don't ask.

Yes, I remember that 3 speed cooling fan. Mine was 3 separate speeds. Didn’t take much to get low speed running, only after really spirted sessions would it be up on high. And we had a BUNCH of them...If you caught it in between songs you would hear the relay click up on the next speed. We torcher’ed our equipment back then. But that Hafler never flinched.
+1 on the Alcon 535 amp, mine is a 535 II.
My old but rebuilt GAS Ampzilla sounds really, really good, but my new SST Son of Ampzilla II is better still. The old Ampzilla has new 20amp Toshibas replacing the 15amp Motorolas for the output transistors 
My 8b and 7 make me smile.  Almost as old as me.  This is my starting point or entry into the hobby.  I know there’s better, but I’m happy. For now.

Still using My Pass X350 more than likely will recap. However, I`ve been informed of a minor mod that will give me better performance plan on enjoy it another 20 years. WOW Ill be 95years young lol.
@bpoletti / @nitrobob -  The later DH-500/DH-220 driver boards had polypropylene caps, from C1, throughout (same board in both, btw).           Hafler offered upgrade kits that contained all those caps (Sprague Orange Drops), of which I still have one.                         They went through three different power switches, over the years, before they found one that would handle the inrush current.     I have three of the last Carling switches, with the updated wiring diagrams.                  The earliest 500/220 amps had 10uF electrolytics, at the board input, later replaced with 2uF polypropylene.   Hafler offered a DH-203 (Bailey Mod for C1) upgrade kit, of which I have two (4 caps).                         I mention all that because I’d happily donate (gratis) those parts, to any party/parties interested in resurrecting their older Hafler(s).                                                            This company offers MOSFETs, with which to replace those used in Haflers, but- to my knowledge, NOT as matched NPN/PNP pairs/sets, which is critical: http://www.exicon.info/
Adcom 535 ll. Nelson Pass design. Picked it up at the local flea for $40 and invested $100 to get it in top shape. Won't ever get rid of it, will always be my backup. Typical Nelson Pass detail and transparency. Specs state 40 watts/channel but like most Pass products a very moderate rating.
The Sim audio w5 was an unbelievably good sounding amp especially for the money it was $5,000 Canadian.
Any fans of Brown Electronic Labs (BEL) out there?    I had a 1001 MkII, was sad that I let it get away, so had to pick a MkV the first time I found a used one.    Wonderful amps!
I’ve the pleasure of owning as new vintage Yamaha amplifiers. A Pc2002m driving 4 infinity infinitesimal 0.2’s wall mounted.
A Pc4002m driving 2 base towers, and finally a Pc5002m driving the 2 mid/treble
panels. The Beta’s will drop to 1 ohm so certainly in efficient. The sound is clean with clipping out of the question if you intend on staying in the building. I’ve seen a few big name amps smoke trying to drive these speakers. Won’t be selling any of this stuff anytime soon. 
Hafler DH-220 bought new in 1984 for $329 - which is what a used version is worth today. Still drive my MG-1.5QRs very well.