Question about OT Headroom

[Joseph Meditz]

https://taweber.powweb.com/store/kits_60b.htm#6M45H

WOT45HHR Higher Headroom, punchy, dynamic
WOT45LHR Lower Headroom, balsy overdrive

This kit has two options for the OT as described above, copied
verbatim. The OTs are both rated for 45W and have the same impedances.
I'm curious as to what in the design would account for the difference
in headroom.

TIA,
Joe

[maxhifi]

"Joseph Meditz" > wrote in message
ups.com...
> https://taweber.powweb.com/store/kits_60b.htm#6M45H
>
> WOT45HHR Higher Headroom, punchy, dynamic
> WOT45LHR Lower Headroom, balsy overdrive
>
> This kit has two options for the OT as described above, copied
> verbatim. The OTs are both rated for 45W and have the same impedances.
> I'm curious as to what in the design would account for the difference
> in headroom.
>
> TIA,
> Joe
>

These are clearly made for a guitar amplifier. Low headroom means the
transformer core will start to saturate, and add harmonic distortion to the
signal, when a lower signal voltage is applied compared with the other
model. This could be desirable in a guitar amplifier.

Early saturation is related to the magnetic flux density in the transformer
core.

When a voltage is applied to the primary of a transformer, the magnetic flux
density in the core, and therefore the secondary voltage will change
proportionally until the saturation point is hit, and after that, there is a
non-linear relationship (harmonic distortion is produced because the signal
has entered this non-linar region of operation)

This basically means that the high headroom model will have either more (or
bigger), or better quality laminations, as there is a limit to how much
magnetic flux density a certain cross sectional area of 'iron' can handle.

The above is also the reason why good tube amplifiers tend to be heavy.

[Eeyore]

Joseph Meditz wrote:

> https://taweber.powweb.com/store/kits_60b.htm#6M45H
>
> WOT45HHR Higher Headroom, punchy, dynamic
> WOT45LHR Lower Headroom, balsy overdrive
>
> This kit has two options for the OT as described above, copied
> verbatim. The OTs are both rated for 45W and have the same impedances.
> I'm curious as to what in the design would account for the difference
> in headroom.

Ah ! A guitar amp. Turns ratio I'd guess. One will give higher peaks (
probably best for lead ) but the other will deliver solid consistent power
( probably best for bass ).

Graham

[Ned Carlson]

Joseph Meditz wrote:
> https://taweber.powweb.com/store/kits_60b.htm#6M45H
>
> WOT45HHR Higher Headroom, punchy, dynamic
> WOT45LHR Lower Headroom, balsy overdrive
>
> This kit has two options for the OT as described above, copied
> verbatim. The OTs are both rated for 45W and have the same impedances.
> I'm curious as to what in the design would account for the difference
> in headroom.

Basically, if you choose "low headroom" you're getting
a smaller, cheaper, output transformer for the same
money (sneaky, huh?). I would go for the bigger iron
in all cases, there's other, better, ways to get
distortion.. history bears my point out. Few people
are trading Super Reverbs for Pro Reverbs, Deluxes
for Princetons, JCM 900 for JCM 800, or, overall, sticking
smaller transformers in place of larger ones very
often. That's not to say that there aren't good, small
transformers, but for even money, IMHO, go for the bigger
iron.




--
Ned Carlson
SW side of Chicago, USA
www.tubezone.net

[Joseph Meditz]

Ned Carlson wrote:
> Joseph Meditz wrote:
> > https://taweber.powweb.com/store/kits_60b.htm#6M45H
> >
> > WOT45HHR Higher Headroom, punchy, dynamic
> > WOT45LHR Lower Headroom, balsy overdrive
> >
> > This kit has two options for the OT as described above, copied
> > verbatim. The OTs are both rated for 45W and have the same impedances.
> > I'm curious as to what in the design would account for the difference
> > in headroom.
>
> Basically, if you choose "low headroom" you're getting
> a smaller, cheaper, output transformer for the same
> money (sneaky, huh?).

Thanks. That's what I suspected. But since their weights were not
listed it was just a guess on my part, not to mention that I don't know
the first thing about transformer design.

> I would go for the bigger iron
> in all cases, there's other, better, ways to get
> distortion.. history bears my point out. Few people
> are trading Super Reverbs for Pro Reverbs, Deluxes
> for Princetons, JCM 900 for JCM 800, or, overall, sticking
> smaller transformers in place of larger ones very
> often. That's not to say that there aren't good, small
> transformers, but for even money, IMHO, go for the bigger
> iron.
>

Good advice.

Joe

>
>
>
> --
> Ned Carlson
> SW side of Chicago, USA
> www.tubezone.net

[Joseph Meditz]

Ned Carlson wrote:
> Joseph Meditz wrote:
> > https://taweber.powweb.com/store/kits_60b.htm#6M45H
> >
> > WOT45HHR Higher Headroom, punchy, dynamic
> > WOT45LHR Lower Headroom, balsy overdrive
> >
> > This kit has two options for the OT as described above, copied
> > verbatim. The OTs are both rated for 45W and have the same impedances.
> > I'm curious as to what in the design would account for the difference
> > in headroom.
>
> Basically, if you choose "low headroom" you're getting
> a smaller, cheaper, output transformer for the same
> money (sneaky, huh?).

Thanks. That's what I suspected. But since their weights were not
listed it was just a guess on my part, not to mention that I don't know
the first thing about transformer design.

> I would go for the bigger iron
> in all cases, there's other, better, ways to get
> distortion.. history bears my point out. Few people
> are trading Super Reverbs for Pro Reverbs, Deluxes
> for Princetons, JCM 900 for JCM 800, or, overall, sticking
> smaller transformers in place of larger ones very
> often. That's not to say that there aren't good, small
> transformers, but for even money, IMHO, go for the bigger
> iron.
>

Good advice.

Joe
>
>
>
> --
> Ned Carlson
> SW side of Chicago, USA
> www.tubezone.net

[Eeyore]

Joseph Meditz wrote:

> Ned Carlson wrote:
> > Joseph Meditz wrote:
> > > https://taweber.powweb.com/store/kits_60b.htm#6M45H
> > >
> > > WOT45HHR Higher Headroom, punchy, dynamic
> > > WOT45LHR Lower Headroom, balsy overdrive
> > >
> > > This kit has two options for the OT as described above, copied
> > > verbatim. The OTs are both rated for 45W and have the same impedances.
> > > I'm curious as to what in the design would account for the difference
> > > in headroom.
> >
> > Basically, if you choose "low headroom" you're getting
> > a smaller, cheaper, output transformer for the same
> > money (sneaky, huh?).
>
> Thanks. That's what I suspected. But since their weights were not
> listed it was just a guess on my part, not to mention that I don't know
> the first thing about transformer design.

The information supplied above may be entirely wrong however !

Why not simply ask the vendor ?

Graham

[Joseph Meditz]

Eeyore wrote:
> Joseph Meditz wrote:
>
> > https://taweber.powweb.com/store/kits_60b.htm#6M45H
> >
> > WOT45HHR Higher Headroom, punchy, dynamic
> > WOT45LHR Lower Headroom, balsy overdrive
> >
> > This kit has two options for the OT as described above, copied
> > verbatim. The OTs are both rated for 45W and have the same impedances.
> > I'm curious as to what in the design would account for the difference
> > in headroom.
>
> Ah ! A guitar amp. Turns ratio I'd guess.

No.

Joe

>One will give higher peaks (
> probably best for lead ) but the other will deliver solid consistent power
> ( probably best for bass ).
>
> Graham

[Eeyore]

Joseph Meditz wrote:

> Eeyore wrote:
> > Joseph Meditz wrote:
> >
> > > https://taweber.powweb.com/store/kits_60b.htm#6M45H
> > >
> > > WOT45HHR Higher Headroom, punchy, dynamic
> > > WOT45LHR Lower Headroom, balsy overdrive
> > >
> > > This kit has two options for the OT as described above, copied
> > > verbatim. The OTs are both rated for 45W and have the same impedances.
> > > I'm curious as to what in the design would account for the difference
> > > in headroom.
> >
> > Ah ! A guitar amp. Turns ratio I'd guess.
>
> No.

You *know* it isn't ?

Graham

[Joseph Meditz]

Eeyore wrote:
> Joseph Meditz wrote:
>
> > Eeyore wrote:
> > > Joseph Meditz wrote:
> > >
> > > > https://taweber.powweb.com/store/kits_60b.htm#6M45H
> > > >
> > > > WOT45HHR Higher Headroom, punchy, dynamic
> > > > WOT45LHR Lower Headroom, balsy overdrive
> > > >
> > > > This kit has two options for the OT as described above, copied
> > > > verbatim. The OTs are both rated for 45W and have the same impedances.
> > > > I'm curious as to what in the design would account for the difference
> > > > in headroom.
> > >
> > > Ah ! A guitar amp. Turns ratio I'd guess.
> >
> > No.
>
> You *know* it isn't ?

Why do you doubt it?

>
> Graham