I think I made a mistake

[VictoriaGuy]

Originally Posted by HornTube

Mills sound warm & musical the normal wirewounds do sound restrained and harsh. I'm not delighted about the price of the Mills but the sound is too nice to ignore.

I was joking, mostly.
Where do you buy the Mills- direct(??) or.....
Thanks.

[HornTube]

In your lovely country! At Parts-ConneXion of course.

Go Canada go!
Gretzky for president!

[murphythecat8]

@Horntube: You would change the output transformers? Why? I thought that the dynaco st-70 transformers was of good quality... You would actually change them?

[HornTube]

Originally Posted by murphythecat8

@Horntube: You would change the output transformers? Why? I thought that the dynaco st-70 transformers was of good quality... You would actually change them?

I would change nearly every output transformer & choke to Lundahl. Mains transformer is not that important. To equal Lundahl with a conventional transformer you need a huge one - it must be at least 2 times the size of a Lundahl. The Lundahl chokes doing wonderful things to the sound - never believed that it is worth to pay so much for the Lundahls.

[murphythecat8]

Originally Posted by HornTube

I would change nearly every output transformer & choke to Lundahl. Mains transformer is not that important. To equal Lundahl with a conventional transformer you need a huge one - it must be at least 2 times the size of a Lundahl. The Lundahl chokes doing wonderful things to the sound - never believed that it is worth to pay so much for the Lundahls.

Okay you really learn me something here. I will get lundahl transformers.

thanks a lot, I will probably follow all of your advise you earlier gave me about resistors .


Edit: ohhh, they are expensive! So I need two chokes and two output transformers?!?
which model lundahl of ouput transformer and chokes do you recommend for my amp? Cheapest option, or do I even have a choice. I'm really starting in this hobby, so would need a couple of direction. I'm reading a whole lot on the net, but would need some confirmation and for now honestly I have no idea how to choose the right output transformer and chokes



Jay

[HornTube]

If you can afford it change the mains to Lundahls too. Give me the specs for your mains & output trans please.

[VictoriaGuy]

Originally Posted by murphythecat8

ohhh, they are expensive! So I need two chokes and two output transformers?!?
which model lundahl of ouput transformer and chokes do you recommend for my amp?

You really should get the amp running properly before you start a lot of 'upgrades', IMO.

But, if you spend a lot of money, I am sure you will hear a difference!

[VictoriaGuy]

Originally Posted by HornTube

In your lovely country! At Parts-ConneXion of course.

Oh, tho$e guys!

Why I have to order (Canadian) Hammond transformers from the USA!
Take the AES price, add at least $10 (US) and you have the Part$Conexion price...simple.
And PartsConeXion is about 30 miles from the Hammond plant/warehouse.

[fandersen]

Originally Posted by VictoriaGuy

Oh, tho$e guys!

Why I have to order (Canadian) Hammond transformers from the USA!
Take the AES price, add at least $10 (US) and you have the Part$Conexion price...simple.
And PartsConeXion is about 30 miles from the Hammond plant/warehouse.

The best hammond prices I have found is a1parts.com in Toronto.

[richwalters]

Originally Posted by HornTube

the normal wirewounds do sound restrained and harsh.

In that case they are reacting exactly as they should do by being proper resistors with ideal temp coefficient. It's the peak current issue that causes alot of the conventional film types to soften up on impulse transients which they cannot handle. Remember, output stages displaying transient overshoot in the o/p tranny (see squarewave test enclosed) will show a reflected spike current in the cathode resistors and this is nasty for composition m/o film type resistors.Wirewounds are perfect for this app and there is no getting away from this fact.

The output stage should hold up whatever signal is presented to it.

If you claim the sound is different by changing the o/p stage cathode resistor types, then one should really examine where the sonic differences are occurring, perhaps in the earlier stages, or blame it on an average quality o/p tranny. The photo hold true for all output stages......from 7W upwards and je higher the power the more care in component choice.
The first casualty with a well designed o/p stage being overworked is the screen resistor ratings acting as fuses. If they blow that would be a warning which has to be investigated.

richy