It was only when I saw the IEC on the rear that I realised it was not 1960s,
scuffed red mock leather covering, large thick leather handle, "ivory" knobs
, that cream stove enamel used on a lot of medical kit etc of the era after
the crackle finish of the 40s/50s.
Now I've seen it all. To get the amp out you need to remove a speaker to
release the speaker wires internally. But its a dummy speaker, presumably
the 2 in the model name means 2 speakers. Basket , suspension , kevlar
looking skirt, and cone , only. No pig tails or holes for pigtails or Voice
coil or magnet. So if these were off a production line, how were they
further processed? 4x3 sets of holes in the basket for what I would have
thought were screw holes for a magnet , but sealed off by the seated cone.
Would they glue in VC to the cone and magnet glued in to the basket with
some sort of active monitoring of sound output , while posistioning in the
uncured glue?
Problem is the otherwise Ashdown Bass amp common symptom of loss of output ,
returning a few minutes later, but this one will then continue for an hour
or more with no drop-out. Not had a chance to power up yet , to investigate

On 11/06/2013 08:40, N_Cook wrote:
It was only when I saw the IEC on the rear that I realised it was not 1960s,
scuffed red mock leather covering, large thick leather handle, "ivory" knobs
, that cream stove enamel used on a lot of medical kit etc of the era after
the crackle finish of the 40s/50s.
Now I've seen it all. To get the amp out you need to remove a speaker to
release the speaker wires internally. But its a dummy speaker, presumably
the 2 in the model name means 2 speakers. Basket , suspension , kevlar
looking skirt, and cone , only. No pig tails or holes for pigtails or Voice
coil or magnet. So if these were off a production line, how were they
further processed? 4x3 sets of holes in the basket for what I would have
thought were screw holes for a magnet , but sealed off by the seated cone.
Would they glue in VC to the cone and magnet glued in to the basket with
some sort of active monitoring of sound output , while posistioning in the
uncured glue?
Problem is the otherwise Ashdown Bass amp common symptom of loss of output ,
returning a few minutes later, but this one will then continue for an hour
or more with no drop-out. Not had a chance to power up yet , to investigate


The answer is in the name. It's not a dummy speaker, but a passive
'acoustic radiator' Surely you have seen one of these before? They are
not uncommon.

Ron

Ron Johnson wrote in message
...
On 11/06/2013 08:40, N_Cook wrote:
It was only when I saw the IEC on the rear that I realised it was not
1960s,
scuffed red mock leather covering, large thick leather handle, "ivory"
knobs
, that cream stove enamel used on a lot of medical kit etc of the era
after
the crackle finish of the 40s/50s.
Now I've seen it all. To get the amp out you need to remove a speaker to
release the speaker wires internally. But its a dummy speaker,
presumably
the 2 in the model name means 2 speakers. Basket , suspension , kevlar
looking skirt, and cone , only. No pig tails or holes for pigtails or
Voice
coil or magnet. So if these were off a production line, how were they
further processed? 4x3 sets of holes in the basket for what I would have
thought were screw holes for a magnet , but sealed off by the seated
cone.
Would they glue in VC to the cone and magnet glued in to the basket with
some sort of active monitoring of sound output , while posistioning in
the
uncured glue?
Problem is the otherwise Ashdown Bass amp common symptom of loss of
output ,
returning a few minutes later, but this one will then continue for an
hour
or more with no drop-out. Not had a chance to power up yet , to
investigate


The answer is in the name. It's not a dummy speaker, but a passive
'acoustic radiator' Surely you have seen one of these before? They are
not uncommon.

Ron


Never seen one . I've seen holes in boxes called adiabatic resonators , yes,
so I'd believe anything was possible.
What is an active loudspeaker , if not an acoustic radiator? The company
blurb refers to 2 speakers which to my mind implies 2 of the same sort of
speaker . Eiter 2x active speakers or 2x passive speakers which would likely
result in a lot of returns

On 11/06/2013 11:09, N_Cook wrote:
Ron Johnson wrote in message
...
On 11/06/2013 08:40, N_Cook wrote:
It was only when I saw the IEC on the rear that I realised it was not
1960s,
scuffed red mock leather covering, large thick leather handle, "ivory"
knobs
, that cream stove enamel used on a lot of medical kit etc of the era
after
the crackle finish of the 40s/50s.
Now I've seen it all. To get the amp out you need to remove a speaker to
release the speaker wires internally. But its a dummy speaker,
presumably
the 2 in the model name means 2 speakers. Basket , suspension , kevlar
looking skirt, and cone , only. No pig tails or holes for pigtails or
Voice
coil or magnet. So if these were off a production line, how were they
further processed? 4x3 sets of holes in the basket for what I would have
thought were screw holes for a magnet , but sealed off by the seated
cone.
Would they glue in VC to the cone and magnet glued in to the basket with
some sort of active monitoring of sound output , while posistioning in
the
uncured glue?
Problem is the otherwise Ashdown Bass amp common symptom of loss of
output ,
returning a few minutes later, but this one will then continue for an
hour
or more with no drop-out. Not had a chance to power up yet , to
investigate


The answer is in the name. It's not a dummy speaker, but a passive
'acoustic radiator' Surely you have seen one of these before? They are
not uncommon.

Ron


Never seen one . I've seen holes in boxes called adiabatic resonators , yes,
so I'd believe anything was possible.
What is an active loudspeaker , if not an acoustic radiator? The company
blurb refers to 2 speakers which to my mind implies 2 of the same sort of
speaker . Eiter 2x active speakers or 2x passive speakers which would likely
result in a lot of returns



If you only had two passive speakers, no sound would come out! You could
save a lot of money on the amplifiers mind
The passive radiator is a way of lowering the tuning of the cabinet
whist keeping a small volume (hence size) and without resorting to bass
ports

Ron

"Ron Johnson" wrote in message
...
On 11/06/2013 08:40, N_Cook wrote:
It was only when I saw the IEC on the rear that I realised it was not
1960s,
scuffed red mock leather covering, large thick leather handle, "ivory"
knobs
, that cream stove enamel used on a lot of medical kit etc of the era
after
the crackle finish of the 40s/50s.
Now I've seen it all. To get the amp out you need to remove a speaker to
release the speaker wires internally. But its a dummy speaker, presumably
the 2 in the model name means 2 speakers. Basket , suspension , kevlar
looking skirt, and cone , only. No pig tails or holes for pigtails or
Voice
coil or magnet. So if these were off a production line, how were they
further processed? 4x3 sets of holes in the basket for what I would have
thought were screw holes for a magnet , but sealed off by the seated
cone.
Would they glue in VC to the cone and magnet glued in to the basket with
some sort of active monitoring of sound output , while posistioning in
the
uncured glue?
Problem is the otherwise Ashdown Bass amp common symptom of loss of
output ,
returning a few minutes later, but this one will then continue for an
hour
or more with no drop-out. Not had a chance to power up yet , to
investigate


The answer is in the name. It's not a dummy speaker, but a passive
'acoustic radiator' Surely you have seen one of these before? They are not
uncommon.

Ron


I was gonna say that as well ! :-)

Arfa

"N_Cook" wrote:
It was only when I saw the IEC on the rear that I realised it was not 1960s,
scuffed red mock leather covering, large thick leather handle, "ivory" knobs
, that cream stove enamel used on a lot of medical kit etc of the era after
the crackle finish of the 40s/50s.
Now I've seen it all. To get the amp out you need to remove a speaker to
release the speaker wires internally. But its a dummy speaker, presumably
the 2 in the model name means 2 speakers. Basket , suspension , kevlar
looking skirt, and cone , only. No pig tails or holes for pigtails or Voice
coil or magnet. So if these were off a production line, how were they
further processed? 4x3 sets of holes in the basket for what I would have
thought were screw holes for a magnet , but sealed off by the seated cone.
Would they glue in VC to the cone and magnet glued in to the basket with
some sort of active monitoring of sound output , while posistioning in the
uncured glue?
Problem is the otherwise Ashdown Bass amp common symptom of loss of output ,
returning a few minutes later, but this one will then continue for an hour
or more with no drop-out. Not had a chance to power up yet , to investigate

Normal passive has no coil, but it might be there to damp, mostly over and
under resonance. Most effective below resonance, so the cabinet does not
cause overextension below driver resonance.

Greg

"Ron Johnson"

If you only had two passive speakers, no sound would come out! You could
save a lot of money on the amplifiers mind

** Ha, ha.

The passive radiator is a way of lowering the tuning of the cabinet whist
keeping a small volume (hence size) and without resorting to bass ports

** A passive radiator is simply another form of tuned port - instead of
the moving mass being simply the air enclosed by the tube, the cone of the
radiator acts as the moving mass. The spring is always provided by the air
trapped in the box.

The main advantage is that it allows small cabinets to be tuned to low
frequencies and with a large moving surface area.

In such cases, a similar frequency air only port would be inconveniently
long and have a too small a surface area - the result of which is a high
level of chuffing noise and strong third harmonic generation.

As with an air only port, the cone motion of a radiator supports the output
of the cabinet in the lowest octave and will be the main source of sound at
box resonance.


.... Phil