How much solid state in your amp?

For the three and more legged things
User avatar
Paul Barker
No idea why I do this anymore
Posts: 6874
Joined: Mon May 21, 2007 9:42 pm

How much solid state in your amp?

Post by Paul Barker » Sun Jan 20, 2008 2:20 pm

Presently I use a solid state HT bridge and of course LT bridges, and mosfet ccs four of.

Darren
Old Hand
Posts: 779
Joined: Mon May 21, 2007 10:58 pm
Location: N/Wales
Contact:

Post by Darren » Sun Jan 20, 2008 2:23 pm

I do wonder sometimes if some of use have lost their way :shock:

User avatar
Paul Barker
No idea why I do this anymore
Posts: 6874
Joined: Mon May 21, 2007 9:42 pm

Post by Paul Barker » Sun Jan 20, 2008 2:26 pm

I could use valve ht I could use valve pass reg to get ht down for the stages I use mosfets in that role, I could use valve ccs's which is the other function of the mosfet.

But it takes longer to build requires more heater supplies plenty more real estate weight cost unreliability.

Mosfets are totally unreliable if you get it wrong too but if you treat them right totally reliable.

Darren
Old Hand
Posts: 779
Joined: Mon May 21, 2007 10:58 pm
Location: N/Wales
Contact:

Post by Darren » Sun Jan 20, 2008 2:26 pm

I'll expand,

I've never head any SS device in a valve amp improve it, inc heaters.

Different yes, improvement would be harder to judge, it changes things but is it for the better overall?

User avatar
Paul Barker
No idea why I do this anymore
Posts: 6874
Joined: Mon May 21, 2007 9:42 pm

Post by Paul Barker » Sun Jan 20, 2008 2:26 pm

as for the sound I would probably prefer it all valved. But life is full of decisions made on more than one basis. This is one of those.

Darren
Old Hand
Posts: 779
Joined: Mon May 21, 2007 10:58 pm
Location: N/Wales
Contact:

Post by Darren » Sun Jan 20, 2008 2:28 pm

I do use SS rects in my current amp. This is the one and only time I hear an improvement.

I guess it's down to drawing 200ma, Not sure, I will experiment with other valve rectifiers.

User avatar
Paul Barker
No idea why I do this anymore
Posts: 6874
Joined: Mon May 21, 2007 9:42 pm

Post by Paul Barker » Sun Jan 20, 2008 2:33 pm

Of course the intended tone can be found surrounding the right valves with the right transformers loads coupling devices etc etc.

Get the valve choice right first and foremost, Then equip it.

Like I said the resistorless capacitorless supply on the egg 1 px25 amp
everyone heard the benefit of the px25 shoulder over the shoulder px4 and finally the balloon px25 over the former. No solid state, u19 rect, 572b and 811a shunt valves two stages VR tube voltage references, masses of inductance.

Bass from that amp was probably my best ever.

A marvelous goal to aim for.

But oh so hard to apply in practice.

With our solid state devices we can achieve remarcably similar result, though I find Black Gates help, wouldn't say you could get anywhere near the quality of the r less c less without Black Gates.

Darren
Old Hand
Posts: 779
Joined: Mon May 21, 2007 10:58 pm
Location: N/Wales
Contact:

Post by Darren » Sun Jan 20, 2008 2:36 pm

Yes, you can get easier control by using SS, sure I'd agree with that.

But at what cost?

User avatar
Paul Barker
No idea why I do this anymore
Posts: 6874
Joined: Mon May 21, 2007 9:42 pm

Post by Paul Barker » Sun Jan 20, 2008 2:37 pm

Belongs in another thread really but BLACK GATES

How are the new boys going to find the sounds we had?

Surely somebody must invent a cap of that quality again, can everything only be going downhill?

User avatar
pre65
Amstrad Tower of Power
Posts: 16649
Joined: Wed Aug 22, 2007 11:13 pm
Location: Ashen Sudbury Suffolk

Post by pre65 » Sun Jan 20, 2008 2:38 pm

Darren wrote: Not sure, I will experiment with other valve rectifiers.
Hi Darren-how about the 6D22s television damper diodes that Andrew I and I use ?

http://www.drtube.com/datasheets/6d22ssvet1997.pdf
People are like stained-glass windows. They sparkle and shine when the sun is out, but when the darkness sets in, their true beauty is revealed only if there is a light from within
Dr Elisabeth Kubler-Ross

G-Popz THE easy listening connoisseur. (Philip)

User avatar
andrew Ivimey
No idea why I do this anymore
Posts: 6171
Joined: Mon Jun 11, 2007 8:33 am
Location: Bedford

Post by andrew Ivimey » Sun Jan 20, 2008 2:41 pm

Yeah right, thanks Philip, fewer 6DS22s for me to break.

I missed 50 X PY500 last week, by a Euro - grrrrrrrrrrr!

Darren
Old Hand
Posts: 779
Joined: Mon May 21, 2007 10:58 pm
Location: N/Wales
Contact:

Post by Darren » Sun Jan 20, 2008 2:41 pm

As this is a SS section perhaps we should bring it back online before we get told off !!!

I do wonder with all the recent SS, talk if peeps are adding so much silicon that some simple SS amps to them do sound acceptable?

Darren
Old Hand
Posts: 779
Joined: Mon May 21, 2007 10:58 pm
Location: N/Wales
Contact:

Post by Darren » Sun Jan 20, 2008 2:43 pm

Hi Phil,

I have around 3000 or more valves at my disposal so maybe I have some to try. I certainly have plenty of others.

I am finding that with my current amp that has LOTS of DEEP base the PS is critical. So to make it easier for now I'm using SS rects that can deliver large instantaneous currents.

I have some good valve rects, so hopefully one can show the SS rects the way? Who knows time will tell.
Last edited by Darren on Sun Jan 20, 2008 2:46 pm, edited 1 time in total.

User avatar
Paul Barker
No idea why I do this anymore
Posts: 6874
Joined: Mon May 21, 2007 9:42 pm

Post by Paul Barker » Sun Jan 20, 2008 2:44 pm

I have used the damper diodes, but just use quite good freds passed through a single schottky, simple no heaters can make a bridge easily, superb bass.

Not saying your way isn't better, this is where I am right now with available time and energy to spend on my valve amp building

User avatar
Paul Barker
No idea why I do this anymore
Posts: 6874
Joined: Mon May 21, 2007 9:42 pm

Post by Paul Barker » Sun Jan 20, 2008 2:48 pm

TBH that amp which Ian linked where the guy drives output valve with fet as though it were a cathode follower, but easier to provide a lower output impedance current drive and incorporates mosfet ccs at every stage so avoiding iron has a place.

Sure it might not be as good as a boatanchor, but it will be 10 times better than any chinease valve amp I have heard, which is what the present bunch of newby's seem to be geting for their experience.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest