I still like my Hafler D110 preamp. very quiet...but had some switch noises that I fixed. Super nice tone controls! great dynamic range

[GeorgeP]

Good for super clean 10V output Distortionless 10hz to 50kHz flat.
Bipolar +/- 18V power supply rails used for ALL amp sections, DC coupled, and almost zero DC off set at outputs. Amazing preamp, but hard to clean controls 4 sure.
I removed the FET timed mute at turn-on, decided to add a relay...much better, and no nonlinearity concerns.

 

[8991XJ]

Hafler made good crap. I still have 2 of the three DH-200 kits I bought new and swapped the third for a pair of tube amps I still have from that 1982-3 trade. Probably not getting rid of any of them. The Haflers sell for so little it isn't worth it and the tube amps sound great.

David Hafler brought excellent sound to the masses with his Dynaco and Hafler company products.

 

[GeorgeP]

Hafler made good crap. I still have 2 of the three DH-200 kits I bought new and swapped the third for a pair of tube amps I still have from that 1982-3 trade. Probably not getting rid of any of them. The Haflers sell for so little it isn't worth it and the tube amps sound great.

David Hafler brought excellent sound to the masses with his Dynaco and Hafler company products.

yes...I still have a Dynaco 120! Very nice 60W / Channel.

 

[Bob Boyer]

Pre-Counterpoint, I had a Hafler 110 preamp and 220 power amp before trading the 110 on a B&K Pro-5 preamp. The 220 drove a pair of Acoustat Model 11s very nicely. Great imaging from that combo.

Hafler gear was no slouch.

 

[e30m3mon]

yes...I still have a Dynaco 120! Very nice 60W / Channel.

I rebuilt my 120 shortly before WOPLing my 400-II ... that Dynaco gave me the confidence to try something more challenging like the 400-II, and then a few other projects. Dynaco was good stuff in its day.

 

[8991XJ]

I still have a Dynaco 120

The Stereo 120 was my first power amp, Kit for this kid in 1970

 

[8991XJ]

Hafler gear was no slouch.

And yet the DH-200s are my worst sounding amps but they still sound great and as I said, I'm keeping em.
Luxman tubes, DNA-1, Citation 22, Luxman M-12, sold the Crown PSA-2 and the Haflers.

 

[wattsabundant]

1978 bought the Dynaco 120/PAT4 from Sound Values. Later bought the Hafler 101 when Stereo Review raved about it. Then bought DH200. Mid 80's did contract work for Sound Values testing Dynaco 400 boards, warranty repairs, production testing. Could have had one of everything of the tube gear, but never took any home. Wish I had some of the tube amps.

Early 90's developed a mosfet amp from the International Rectifier data book to drop in the Dyna 120 chassis. Like so many other projects never got it to market.

 

[8991XJ]

Could have had one of everything of the tube gear, but never took any home. Wish I had some of the tube amps.

Looking back we missed the boat with the Dynaco Tube gear. I needed power for my AR-5 speakers and the Stereo 120 got good reviews, what didn't, really? Got the 60wpc ss unit instead of the 35wpc tube unit. Did fine, have much better tubes now.

I was one that once I learned that the old-fashioned tube amps were a thing, later 70s, I thought the way to go was with a tube pre and ss power because the cost of power tubes could be significant and one could get tube sound from the pre. In the early 70s there was a strong move to the ss side as it was the new thing...and many folks said better, well maybe not.

 

[WOPL Sniffer]

HUH????

 

[e30m3mon]

Looking back we missed the boat with the Dynaco Tube gear. I needed power for my AR-5 speakers and the Stereo 120 got good reviews, what didn't, really? Got the 60wpc ss unit instead of the 35wpc tube unit. Did fine, have much better tubes now.

I was one that once I learned that the old-fashioned tube amps were a thing, later 70s, I thought the way to go was with a tube pre and ss power because the cost of power tubes could be significant and one could get tube sound from the pre. In the early 70s there was a strong move to the ss side as it was the new thing...and many folks said better, well maybe not.

As they say about hindsight. I read your post and can identify 100% with audio stuff in the late 70s and into the 80s, until I became a homeowner and all my money went a whole different direction! In retrospect, the house was a far better investment than most of the stereo stuff I bought...equity is a thing!

 

[mlucitt]

Did the Dynaco 120 really use a coil/inductor wound around the electrolytic capacitors?

 

[Vynuladikt]

Yes I believe it did. I remember seeing it in a service manual for something along those lines.

 

[e30m3mon]

Did the Dynaco 120 really use a coil/inductor wound around the electrolytic capacitors?

It sure did ... we hand-wrapped that solid white wire around one of the smaller diameter caps as a form and then stretched it over the output caps. The originals were much larger diameter - as were most older caps back in the 70s

 

[Gepetto]

Did the Dynaco 120 really use a coil/inductor wound around the electrolytic capacitors?

Yes, it definitely did...was considered novel at the time of introduction

 

[Bob Boyer]

I seem to remember wrapping the caps in my SCA-80Q kit, as well. Don't hold me to it but I'm guessing it was something of the norm on their SS stuff?

 

[mlucitt]

It sure did ... we hand-wrapped that solid white wire around one of the smaller diameter caps as a form and then stretched it over the output caps. The originals were much larger diameter - as were most older caps back in the 70s

How were those coils/inductors connected and what was the improvement (if any)? We are not doing that today.
I am wondering if it was novel or a novelty...

 

[e30m3mon]

I believe the coil is the inductor (L1) part of an LC filter that works with C8 at the speaker output. The filter rolls off the very high frequencies to help keep the amp stable. Picture of the circuit schematic for reference…

 

[Vynuladikt]

here is an internal shot I grabbed from Update my Dynaco