Any Dynaco Modders 4

[dynaco_dan]

Hi there;

Anyone interested in modifying your Dynaco Stereo 150, 400, 410 or 416 amplifier?

There is a few mods available and suggestions for improving these and other Dynaco equipment.

Anyone interested?

Good luck.

[Guest palomar]

I have a Stereo 150 that I built back in the mid-70s. I'm not interested in getting too crazy, but if there are some simple mods that would noticeabley improve performance, I'd be interested in at least checking them out.

(I like the sound of the amp as is, but if some simple tweaks could make it better, what the heck.

Gary

[Guest kfarrand]

Vern,

Just picked up a Dynaco Stereo 416 (300 Watts per Channel @ 4 Ohms with 8 output transistors per channel - hence the 4-16 designation) and am interested in whatever restoration or mod options are avaiable - although I'd probably prefer to simply restore w/o modifying any circuit topology . . . It seems to be working fine although I've had the left channel cut out several times (intermitttent). It has 2 amp fast blo fuses in it and I've had the Dynaguard kick in once running my AR-3as at the 20 watt Dynaguard setting driving it in the high 90s dB SPL at 1 meter. Would love to pick up another one of these fine amps if I can down the road. The AR-3s really 'sing' hooked up to the Dynaco Stereo 416 !

Still have not repaired my AR-3a with the tweeter damaged in shipping and would like to purchase a front wired AR-3a tweeter for it. I have a rear wired AR-3a tweeter but do not know whether it is 4 or 8 ohm unit. I'd be glad to swap my rear wired tweeter for a front wired unit with anyone so inclined.

Kevin.Manson@Gmail.com

AR-3as 2 Pair # Dynaco A-25s 2 Pair # Nakamichi Tri Tracer 700 # Revox A-77 # Dynaco 416 # Dynaco Stereo 70 # Dynaco PAS 3 (2) # Harman Kardon AVR 520 Receiver # KLH Model Eleven # H. H. Scott LK-72 Integrated Amp # Sony DVP CX985 V DVD/SACD 400 Disk Jukebox # Generation 5 iPod (60 Gig)

[dynaco_dan]

Hi there;

The 416 was Dynaco's biggest, best and last s/s power amplifier before it's demise.

Based on the 400 with double the output transistors and complimentary led's rather than meters to show the output.

The originators of the 416 at Dynaco may or may not credit Frank Van Alstine with the improvements of the design of the 400 or Walt Jung in The Audio Amatuer, The Double Dyna, we will never know.

The amp is occasionaly on ebay and I try to follow when I can.

The amp is subject to much the same problems as the 400 and less so with the 410 amp, being basicly of the same mould.

Go to;

http://home.indy.net/~gregdunn/dynaco/history.html

Lookup the Dyna 400 and download Kevin Boales article.

Any suggestions are an improvement only to amps that may be having difficulties.

Some changeouts are very simple and improve upon the overall stablity, rather than complete gutting for $$$$$$.

Obviously because of it's age there may be other things in need of replacement, such as, main power supply caps, but if you aren't having any power supply problems don't needlessly spend your hard earned money.

>Vern,

>

>Just picked up a Dynaco Stereo 416 (300 Watts per Channel @ 4

>Ohms with 8 output transistors per channel - hence the 4-16

>designation) and am interested in whatever restoration or mod

>options are avaiable - although I'd probably prefer to simply

>restore w/o modifying any circuit topology . . . It seems to

>be working fine although I've had the left channel cut out

>several times (intermitttent).

Until further experimentation or advice comes along, 2 amps is probably a good compromise for a fuse size.

Did you know that the Dynaco can put out full output, extremely brief mind you, even at the Dynaguard 20 setting.

This allows peaks to be undistorted, briefly though.

It has 2 amp fast blo fuses in

>it and I've had the Dynaguard kick in once running my AR-3as

>at the 20 watt Dynaguard setting driving it in the high 90s dB

>SPL at 1 meter. Would love to pick up another one of these

>fine amps if I can down the road.

The AR-3s really 'sing'

>hooked up to the Dynaco Stereo 416 !

I believe that the amp can put out something like 600 watt peaks single channel driving a 4 ohm speaker.

>Still have not repaired my AR-3a with the tweeter damaged in

>shipping and would like to purchase a front wired AR-3a

>tweeter for it.

I received a damaged in transit mid range, the plastic mounting frame is quite broken up along one side including a mounting hole, I'll be attempting a repair when I have some free time this summer.

The seller used peanuts for packing and the box was only slightly larger that the heavy driver.

Peanuts were used with this shape and size was a really unwise move for USPS transit or other, offers no support.

If you have a digital VOM check across the tweeter and the readings should be about 2.75 ohms if it is a 4 ohm tweeter, about 5.75 ohms if it is an 8 ohm tweeter.

I have a rear wired AR-3a tweeter but do not

>know whether it is 4 or 8 ohm unit. I'd be glad to swap my

>rear wired tweeter for a front wired unit with anyone so

>inclined.

>

>Kevin.Manson@Gmail.com

>

>AR-3as 2 Pair # Dynaco A-25s 2 Pair # Nakamichi Tri Tracer 700

># Revox A-77 # Dynaco 416 # Dynaco Stereo 70 # Dynaco PAS 3

>(2) # Harman Kardon AVR 520 Receiver # KLH Model Eleven # H.

>H. Scott LK-72 Integrated Amp # Sony DVP CX985 V DVD/SACD 400

>Disk Jukebox # Generation 5 iPod (60 Gig)

Nice Dyna equipment. MMMMMMMMMM

This is my second time I wrote this up, it would not save the other day.