Vintage amplifiers that could challenge or approach current state of the art amplifiers

[precisionav]

That's exactly what a good amp is like up to it's clipping point or point where distortion starts.

That's why I'm a fan of ample headroom.

 

[precisionav]

Epic specs. What year was the hafler released?

Early 80's, not sure of exact year. I modified mine in 2002 with upgraded circuit boards and new power supply caps. In stock form it sounded great, I just wanted to freshen it up and its served me very well these last 20 years.

 

[mhardy6647]

That Hafler guy -- he had mad skilz.

DSC_9819 by Mark Hardy, on Flickr
Dynaco QD-1 front by Mark Hardy, on Flickr

(all borrowed images, 'cept the Dyna 'stack' and the QD-1)

 

[precisionav]

That Hafler guy -- he had mad skilz.

View attachment 115217
View attachment 115216
DSC_9819 by Mark Hardy, on Flickr
Dynaco QD-1 front by Mark Hardy, on Flickr
View attachment 115218

(all borrowed images, 'cept the Dyna 'stack' and the QD-1)

Yes he did! Intelligent engineering combined with quality manufacturing accomplishes great things.

 

[tmtomh]

Epic specs. What year was the hafler released?

Those specs are copyrighted 1987, which sounds about right. My memory and experience when I was first getting into hi-fi in the '80s as a teenager is that Adcom and Hafler were sort of the Big Two when it came to affordable, well-performing high-current amps.

 

[RoyB]

A properly biased Yamaha M series amplifier is pretty hard to beat.....I've been listening to an M45 for the last week on Magnapan MMGs, KEF 103.2, B&W DM601 and ELAC 2.0/6.2.......Brings all of them to life!

 

[restorer-john]

Those specs are copyrighted 1987, which sounds about right. My memory and experience when I was first getting into hi-fi in the '80s as a teenager is that Adcom and Hafler were sort of the Big Two when it came to affordable, well-performing high-current amps.

These specs from 1985 always make me smile.

And the smaller brother...

Big Hitachi Mosfet based Perreauxs.

 

[frullo]

These specs from 1985 always make me smile.

View attachment 115286

And the smaller brother...
View attachment 115288

Big Hitachi Mosfet based Perreauxs.

"Anyone with true HiFi experience knows that it is practically impossible to operate loudspeakers and electronics within the strict limits of their supported powers without distortion. With inefficient loudspeakers and with reactive load it is in fact absolutely normal for amplifiers to clip and for their protections to operate even at output voltage levels much lower than the rated maximums. So the fact that the amp has 0.000001% distortion at 100 Watts and 10% distortion at 105 Watts means that there will be a (short) amount of distorted signal at practically all but those listening. of "plin-plin" music.

Now it happens that tube amps may have three zeros (after the decimal point) of distortion more, but on the other hand they saturate by accepting in input signals even 12-18 dB higher than the maximum linear ones, sending out a signal still clean enough to be acceptable to listening. And then tube amps do NOT have current protectors that suddenly open the final transistors just as they are dissipating the reactive back-EMFs sent back by the speakers to ground ... Still a good reason why - for the same power - tube tubes (especially non-counteractivated ones) eat up any SS amp."

"
Let's imagine that I want to set up a production of power amps, more than anything else in order to make possible a significant leap in high quality on the design of the speakers. It is clear that I would design a power amp with current output and without feedback.

The current output (= damping factor lower than 0.01, to understand) would allow me to reduce the distortion of the speakers by a dozen times, as well as having other advantages that are the real "plus" that explains the secret of the sound of my systems, from the Systems-Provocation (2009) onwards.

The absence of feedback would be necessary to obtain a clipping so gradual as to make it possible to choose a moderate power (e.g. 35-40 Watt), which proved to be absolutely sufficient for the upper channels (= sub excluded) of my installations. So I could use some valves, simplifying future assistance, which would be limited to replacing the tubes, since the rest would be practically indestructible.

Maybe, to really minimize the distortion (below saturation) I would use the Feedforward technique, namely that of the Quad 405 and the Benchmark AHB2.

The result would be a totally revolutionary power amp whose sound is quite obvious that it would pulverize that of any commercial proposal, of course if used with really efficient speakers, let's say from 100 dB / 1W / 1m upwards.

NOW BUT BEWARE ... A finale like this would end up very last in the standings if tried by ASR and therefore would lose any possibility of a foreign market, if I wanted to offer it for sale, for example on Amazon or in e-commerce.

I'm just stating that those who measure and - above all - those who classify SHOULD HAVE CLEAR IDEAS on how much each measured parameter is actually significant in terms of listening performance. And here the example that I can bring to attention is that of our local Audioreview, which since its beginnings has proposed measurements of the distortion and maximum power of the amps both on resistive load (8 and 4 ohm) and on reactive load (+ / - 60 degrees), putting the reader in a position to identify those very rare amps that behaved equally in all conditions: and if I'm not mistaken they can be counted on only one hand ... And - it happens - they all play splendidly."

Source: http://www.hifi-forumlibero.it/phpBB3/viewtopic.php?f=5&t=9448

 

[SIY]

"Anyone with true HiFi experience knows that it is practically impossible to operate loudspeakers and electronics within the strict limits of their supported powers without distortion. With inefficient loudspeakers and with reactive load it is in fact absolutely normal for amplifiers to clip and for their protections to operate even at output voltage levels much lower than the rated maximums. So the fact that the amp has 0.000001% distortion at 100 Watts and 10% distortion at 105 Watts means that there will be a (short) amount of distorted signal at practically all but those listening. of "plin-plin" music.

Now it happens that tube amps may have three zeros (after the decimal point) of distortion more, but on the other hand they saturate by accepting in input signals even 12-18 dB higher than the maximum linear ones, sending out a signal still clean enough to be acceptable to listening. And then tube amps do NOT have current protectors that suddenly open the final transistors just as they are dissipating the reactive back-EMFs sent back by the speakers to ground ... Still a good reason why - for the same power - tube tubes (especially non-counteractivated ones) eat up any SS amp."

"
Let's imagine that I want to set up a production of power amps, more than anything else in order to make possible a significant leap in high quality on the design of the speakers. It is clear that I would design a power amp with current output and without feedback.

The current output (= damping factor lower than 0.01, to understand) would allow me to reduce the distortion of the speakers by a dozen times, as well as having other advantages that are the real "plus" that explains the secret of the sound of my systems, from the Systems-Provocation (2009) onwards.

The absence of feedback would be necessary to obtain a clipping so gradual as to make it possible to choose a moderate power (e.g. 35-40 Watt), which proved to be absolutely sufficient for the upper channels (= sub excluded) of my installations. So I could use some valves, simplifying future assistance, which would be limited to replacing the tubes, since the rest would be practically indestructible.

Maybe, to really minimize the distortion (below saturation) I would use the Feedforward technique, namely that of the Quad 405 and the Benchmark AHB2.

The result would be a totally revolutionary power amp whose sound is quite obvious that it would pulverize that of any commercial proposal, of course if used with really efficient speakers, let's say from 100 dB / 1W / 1m upwards.

NOW BUT BEWARE ... A finale like this would end up very last in the standings if tried by ASR and therefore would lose any possibility of a foreign market, if I wanted to offer it for sale, for example on Amazon or in e-commerce.

I'm just stating that those who measure and - above all - those who classify SHOULD HAVE CLEAR IDEAS on how much each measured parameter is actually significant in terms of listening performance. And here the example that I can bring to attention is that of our local Audioreview, which since its beginnings has proposed measurements of the distortion and maximum power of the amps both on resistive load (8 and 4 ohm) and on reactive load (+ / - 60 degrees), putting the reader in a position to identify those very rare amps that behaved equally in all conditions: and if I'm not mistaken they can be counted on only one hand ... And - it happens - they all play splendidly."

Source: http://www.hifi-forumlibero.it/phpBB3/viewtopic.php?f=5&t=9448

I wish my wife was awake. She speaks excellent Italian and would tell me how to say, "This is an amazing pile of stompwaffle" properly.

 

[frullo]

This is an amazing pile of stompwaffle

No translation for this. But I understand your point. We are just evaluating different points of view.

 

[frullo]

I wish my wife was awake. She speaks excellent Italian and would tell me how to say, "This is an amazing pile of stompwaffle" properly.

By the way, could you kindly explain why this is an " incredibile mucchio di cazzate" (closest translation to "amazing pile of stompwaffle")?

 

[SIY]

By the way, could you kindly explain why this is an " incredibile mucchio di cazzate" (closest translation to "amazing pile of stompwaffle")?

Because it's technically incorrect, data-free, lame excuses for badly designed and executed products?

 

[ZolaIII]

I doubt any current one will come close to this one regarding it's visuals and of course it also mesured great.

Hitachi HMA-8500 Mk II Review

 

[Plcamp]

Hafler xl280 and Adcom 535II are my old favourites. The XL amps were claimed to be definitively perfect when adjusted with a null test. I haven’t tried the test as I use it to power open baffles. I should try it on my paradigms.

Hafler XL-280 power amplifier

www.stereophile.com

 

[RoyB]

FRULLO....Amazing post. Thanks for sharing this information. I've long contended that the Tom Foolery that is happening in modern (SS) amplifier design absolutely messes with the final listening experience. I have a Tubes4HiFi ST120 60w/ch Dynaco clone and a Pass Labs First Watt F5v2 and both are rather simple designs vs todays more complicated amplifiers......And both sound amazing....but most likely measure poorly. My YAMAHA M45 and Cambridge Audio 840 AZUR will measure much better, but they sound sterile. Not bad, and many folks prefer this type of sound. And had I not built the tube amplifier or bought the First Watt, I would have been totally content with either......

 

[NiagaraPete]

I’m tempted to send Amir one of my Linn amps to see how it does.

 

[DSJR]

FRULLO....Amazing post. Thanks for sharing this information. I've long contended that the Tom Foolery that is happening in modern (SS) amplifier design absolutely messes with the final listening experience. I have a Tubes4HiFi ST120 60w/ch Dynaco clone and a Pass Labs First Watt F5v2 and both are rather simple designs vs todays more complicated amplifiers......And both sound amazing....but most likely measure poorly. My YAMAHA M45 and Cambridge Audio 840 AZUR will measure much better, but they sound sterile. Not bad, and many folks prefer this type of sound. And had I not built the tube amplifier or bought the First Watt, I would have been totally content with either......

Got to answer - I thought as you did (if not as passionately) until I attended many jazz gigs locally and at a known venue at the time (I'm not a jazz fan, but a pal was and it was a great cheap chance to hear live music as well as still excellent 1950's recordings which were simply done. The 'real life' sound of drums, brass, and even piano's, is 'sterile' and lacking the reverberant halo and 'organic textures' so many audiophiles adore (which is probably compression). My experience years ago of master tapes gave a similar kind of reproduction quality (in the days of multi-mono 1970's rock recordings it came as a stark reminder when compared to the 'nice, organic, blending effects' of higher end vinyl). I remember with great affection that Quad 57 speakers often came closest to the sound of massed strings (they over-did it a bit really, but most box types failed miserably here)

Personally, I'd wean yourself back to the Yamaha (unknown to me) or the Cambridge (complex but used to be very well liked) and try to attend close up, acoustic music of various genres to possibly try to understand what the heck I'm on about (words don't describe it). OK, my choice, but that's my take anyway, so we'll have to beg to differ I hope.

 

[Deleted member 23424]

The Sharp Optonica range

SM4100 and SM7100 especially.

Genuinely outstanding performance I sold the former when I found the letter, then a few caps went on the latter. Would buy both again in a heartbeat.

 

[LTig]

"Anyone with true HiFi experience knows that it is practically impossible to operate loudspeakers and electronics within the strict limits of their supported powers without distortion. With inefficient loudspeakers and with reactive load it is in fact absolutely normal for amplifiers to clip and for their protections to operate even at output voltage levels much lower than the rated maximums. So the fact that the amp has 0.000001% distortion at 100 Watts and 10% distortion at 105 Watts means that there will be a (short) amount of distorted signal at practically all but those listening. of "plin-plin" music.

Now it happens that tube amps may have three zeros (after the decimal point) of distortion more, but on the other hand they saturate by accepting in input signals even 12-18 dB higher than the maximum linear ones, sending out a signal still clean enough to be acceptable to listening. And then tube amps do NOT have current protectors that suddenly open the final transistors just as they are dissipating the reactive back-EMFs sent back by the speakers to ground ... Still a good reason why - for the same power - tube tubes (especially non-counteractivated ones) eat up any SS amp."

"
Let's imagine that I want to set up a production of power amps, more than anything else in order to make possible a significant leap in high quality on the design of the speakers. It is clear that I would design a power amp with current output and without feedback.

The current output (= damping factor lower than 0.01, to understand) would allow me to reduce the distortion of the speakers by a dozen times, as well as having other advantages that are the real "plus" that explains the secret of the sound of my systems, from the Systems-Provocation (2009) onwards.

The absence of feedback would be necessary to obtain a clipping so gradual as to make it possible to choose a moderate power (e.g. 35-40 Watt), which proved to be absolutely sufficient for the upper channels (= sub excluded) of my installations. So I could use some valves, simplifying future assistance, which would be limited to replacing the tubes, since the rest would be practically indestructible.

Maybe, to really minimize the distortion (below saturation) I would use the Feedforward technique, namely that of the Quad 405 and the Benchmark AHB2.

The result would be a totally revolutionary power amp whose sound is quite obvious that it would pulverize that of any commercial proposal, of course if used with really efficient speakers, let's say from 100 dB / 1W / 1m upwards.

Uh huh.

If it 'd be that easy lots of amps would follow this design. Pity that almost all recordings are mixed and mastered through active speakers sporting class AB or D power amps with tons of global negative feedback (Hint: it's almost impossible to design a power amp without any negative feedback - most of those which claim no feedback use local negative feedback).

 

[Sal1950]

For fault finding, the 'ears-brain-system' is absolutely unsurpassed.

So bias never leads folks to believe a superior piece of gear is inferior to the inferior piece?