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Hi all,

Here's an interesting thought:

You have an amplifier, say a Vox AC15, it has a tapped output transformer
giving 15 ohm and 8 ohm speaker impedances.

The question is, is the output stage better loaded with a 15 ohm speaker
which uses the whole of the secondary winding or using an 8 ohm speaker
which effectively leaves the winding between 8 and 16 ohms unterminated!

I know what I think, what are your thoughts?

Amanda

valvewhiz wrote:Hi all,

Here's an interesting thought:

You have an amplifier, say a Vox AC15, it has a tapped output transformer
giving 15 ohm and 8 ohm speaker impedances.

The question is, is the output stage better loaded with a 15 ohm speaker
which uses the whole of the secondary winding or using an 8 ohm speaker
which effectively leaves the winding between 8 and 16 ohms unterminated!

I know what I think, what are your thoughts?

Amanda

Amanda, you lost me on 'Here's...' The only thing I know about amps is what comes out of the front! As I've said before, I bow to your wisdom on all things ampish and honestly wish I had a hundreth of your expertise in that area.

Cheers

Noel

In either case the output stage will be loaded equally well.

Just plug in and crank the bugger up . . . . . . .

rogera wrote:In either case the output stage will be loaded equally well.

Hi Roger,

Exactly as I thought or knew!

On another note I got a Line 6 spider 2 30w amp in for repair,
both output chips exploded!

Amanda

Hi Amanda,
my thoughts on this (takes me back a few years) I would go for the full winding, apart from greater saturation of the core, you would reduce the current flow in the speaker winding. Less chance of a burn-out.

Steve.

valvewhiz wrote:Hi all,

Here's an interesting thought:

You have an amplifier, say a Vox AC15, it has a tapped output transformer
giving 15 ohm and 8 ohm speaker impedances.

The question is, is the output stage better loaded with a 15 ohm speaker
which uses the whole of the secondary winding or using an 8 ohm speaker
which effectively leaves the winding between 8 and 16 ohms unterminated!

I know what I think, what are your thoughts?

Amanda

I guess it could be an important matter in high-end Hi-Fi, not sure it's the case for guitar amps...

Didier

As I said earlier it was a Rhetorical question.

I prefer the idea of a 15 ohm speaker, which is lucky because my Audiom 60 is!

Next time i've got the scope out I may just take a look at what's going
on on the 8 to 16 ohm section of the transformer!

Amanda