Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

On Jan 24, 12:02*pm, Amanda Ripanykhazova
wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. *Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

I would think that if you are getting smoke from the food in a
microwave then you might want to change you microwaving habits or
perhaps the microwave is on the fritz.

On Jan 24, 3:02*pm, Amanda Ripanykhazova
wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. *Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

I had the same settup years ago and it was the same,
worthless. I haven't seen a hood that's effective
without it being vented outside. I don't suppose by
chance it's on an outside wall?

Amanda Ripanykhazova wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

Just vent it outside. How on earthe are you going to filter out grease and smoke
without hugely expensive equipment?

On 1/24/2012 10:02 AM, Amanda Ripanykhazova wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

Typically, there's a option for venting to an outside duct instead of
recycling the air. A lot of times, venting externally is not a option.
Recycling the air might be better than nothing but not by much.

My Samsung microwave has problems with moisture getting into the control
panels which shorts out the switches. This causes the weak overhead
light to cycle on and off. My guess is that my fondness for
slow-roasting pork in the oven below and the cold weather is a factor.
You could say that this is a pork induced electronic glitch.

On Jan 24, 3:23*pm, Chemo the Clown wrote:
On Jan 24, 12:02*pm, Amanda Ripanykhazova
wrote:





Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. *Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

I would think that if you are getting smoke from the food in a
microwave then you might want to change you microwaving habits or
perhaps the microwave is on the fritz.- Hide quoted text -

- Show quoted text -

It's not smoke from the microwave. It's smoke
from the range. It's a microwave that goes over
the range with a vent fan/filter arrangement on the
bottom.

On Jan 24, 12:02*pm, Amanda Ripanykhazova
wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. *Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

You can run your fan filters through the dishwasher which does a lot
more good than hand washing.
You should also see if you can run a cloth on a brush or something up
in the vent to clean it as much as you can once in a while.

On 01/24/12 03:02 pm, Amanda Ripanykhazova wrote:

Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

Our Kenmore (made by LG, I think) has the aluminum mesh filters at the
bottom but also an activated charcoal filter at the top. The former do
collect a lot of grease, and the latter cuts out some of the smell but
needs to be replaced from time to time. We clean the aluminum filters in
the dishwasher; they get discolored, but who cares?

Perce

On Jan 24, 2:30*pm, "
wrote:
On Jan 24, 3:23*pm, Chemo the Clown wrote:









On Jan 24, 12:02*pm, Amanda Ripanykhazova
wrote:

Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. *Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

I would think that if you are getting smoke from the food in a
microwave then you might want to change you microwaving habits or
perhaps the microwave is on the fritz.- Hide quoted text -

- Show quoted text -

It's not smoke from the microwave. *It's smoke
from the range. *It's a microwave that goes over
the range with a vent fan/filter arrangement on the
bottom.

They do make stoves with a vent at the back.

On 1/24/2012 3:50 PM, wrote:
On Jan 24, 3:02 pm, Amanda
wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

I had the same settup years ago and it was the same,
worthless. I haven't seen a hood that's effective
without it being vented outside. I don't suppose by
chance it's on an outside wall?

My hood isn't vented to the outside yet is effective at recirculating
the air. Maybe the filters you use have to be cleaned more often. My
new vent has two of them, where as my old one only had one.

On Jan 24, 3:02*pm, Amanda Ripanykhazova
wrote:


Fans in hoods....................


All I saw was the Fans in Hoods part and thought you were going
to talk about an Eminem concert or something like that.

TJ

We have a 1 year old GE microwave range hood but it directs/exhaust air
thru a 4 inch round duct to outside the roof.


4" is too small for a duct.Usually it specs out for at least 6" or 7"
round duct. It's in the manual.

Ducting to the outside is a definate plus. When I re-did my kitchen
years ago, I gutted the entire area, and noticed there was a stud in
the way where I was going to run the duct up to the roof. Not having
ordered the cabinets yet, I re-designed the layout so that I moved the
stove over another 3" to avoid the stud, thus having clearance to run
a 3 1/4" X10" duct in between the studs, out through the roof.

On 1/24/2012 3:02 PM, Amanda Ripanykhazova wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

If enough people didn't say it already, vent it outside or don't bother.
There are probably charcoal filters available for your unit but don't
expect them to do much good.

On Jan 24, 3:02*pm, Amanda Ripanykhazova
wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. *Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

http://www.amazon.com/GE-JX81B-Recir.../dp/B00081KZ2E

On Jan 24, 3:02*pm, Amanda Ripanykhazova
wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. *Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

None I know of will handle serious cooking, thats why I didnt put my
microwave/ convection oven/ vent over my stove. I put mine ove ra food
prep area where I use electric skillets,toaster....,etc. The built in
light is really nice for areas like that. Wife thought I was nuts for
not putting it over the stove until she got to use it.

Jimmie

Jimmie

On 1/24/2012 2:02 PM, Amanda Ripanykhazova wrote:
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?

The aluminum mesh filters are for trapping grease and as others have
written, you can drop them in a dishwasher to clean them. The filters
do help keep down the grease that gets deposited from the air all over
everything in your kitchen.

TDD

Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke. Which tends to waft
all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

I was wondering whether any other company had married up a microwave
to a fan effectively OR do the newer GE microwaves do any better a job
of sucking up the smoke and filtering it please?


*Check your manual or check with GE to see if there is a carbon filter
available. Some of the microwave/hoods that I have installed came with one.
I'm sorry, but I don't remember which brands. One Frigidaire chimney model
I installed before Christmas had a carbon filter included.

On Tue, 24 Jan 2012 12:02:08 -0800 (PST), Amanda Ripanykhazova
wrote:

Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?....
.... Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

IMO, there is no such built-in that does an adequate job. When I acquire a new
kitchen, the first thing I do is to rip out any overhead microwave and install a
truly functional exhaust hood.

We run our filters through the dishwasher.

-- Larry

On 1/25/2012 6:40 AM, Mikepier wrote:
We have a 1 year old GE microwave range hood but it directs/exhaust air
thru a 4 inch round duct to outside the roof.


4" is too small for a duct.Usually it specs out for at least 6" or 7"
round duct. It's in the manual.

Ducting to the outside is a definate plus. When I re-did my kitchen
years ago, I gutted the entire area, and noticed there was a stud in
the way where I was going to run the duct up to the roof. Not having
ordered the cabinets yet, I re-designed the layout so that I moved the
stove over another 3" to avoid the stud, thus having clearance to run
a 3 1/4" X10" duct in between the studs, out through the roof.


4" is/was a typo. It is indeed a 6".

"Amanda Ripanykhazova" wrote in message
...
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

[cross-posting snipped]

Sounds like you've got an old GE Spacemaker setup, similar to what I have.
The entire unit should vent to the outside. If it doesn't, it wasn't
installed correctly. BTW, you should look to see if there's a small steam
vent panel at the top of the microwave. It has nothing to do with the metal
filters mounted under the M/W but that's the actual microwave filter vent.

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke.

Those filters are strictly for catching grease splatter coming from the
stovetop under the microwave. I can't imagine cooking in such a way that
the entire kitchen fills with smoke. You said you're in an apartment. Have
you asked the apartment manager to have someone take a look at the
ventilation issues? I'm pretty sure they don't want the building to burn
down because there's a problem with the appliance.

all over the apartment before hopefully getting expelled out of
windows. Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

No. The standard way of cleaning them is to soak them in hot soapy water
with a good grease-cutting dish detergent, like Ajax or Dawn. If they're
particulary grungy I scrub them with a Brillo pad.

Jill

On 1/26/2012 9:41 AM, jmcquown wrote:

"Amanda Ripanykhazova" wrote in message
...
Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

Sounds like you've got an old GE Spacemaker setup, similar to what I
have. The entire unit should vent to the outside. If it doesn't, it
wasn't installed correctly.

They are made so that you can have them vent to the outside,
or recirculate. Naturally, venting to the outside is preferable
by far, but that's not always practical.

nancy

On Jan 26, 9:41*am, "jmcquown" wrote:
"Amanda Ripanykhazova" wrote in message

... Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?

We have a GE setup with the microwave positioned over the cooker and a
fan in it with aluminium filters. *As far as I can see, they feed the
air into ducts which must go behind the microwave and out through
vents at the top. No further filtering is done beyond the aluminium
filters?

[cross-posting snipped]

Sounds like you've got an old GE Spacemaker setup, similar to what I have..
The entire unit should vent to the outside. *If it doesn't, it wasn't
installed correctly.

That's not true. I had one and there are definitely
models designed to be installed to vent either
to the outside or to recirculate the air back into
the house after passing through a filter. If vented
into the house, however, they just don't work very
well. But I'd say a large percentage of them are
installed without outside venting because in many
cases the venting is not already there, they are
not going on an outside wall, etc. Typical case
is an older apartment.

Here's a current GE one, they have 11 others
that will recirculate as well:


http://products.geappliances.com/App...Sku=PSA2201RSS



*BTW, you should look to see if there's a small steam
vent panel at the top of the microwave. *It has nothing to do with the metal
filters mounted under the M/W but that's the actual microwave filter vent..

They don't seem to filter much, especially as we tend to cook in such
a way as to give rise to quite a lot of smoke.

Those filters are strictly for catching grease splatter coming from the
stovetop under the microwave.

No, at least some of them include a charcoal filter to try to filter
the air before sending it back into the house. It's just
that they don't work very well because there is only
so much you can do with a 3/8" filter.


*I can't imagine cooking in such a way that
the entire kitchen fills with smoke. *You said you're in an apartment. *Have
you asked the apartment manager to have someone take a look at the
ventilation issues? *I'm pretty sure they don't want the building to burn
down because there's a problem with the appliance.

Ever try cooking Cajun blackend food? Lots of smoke,
which does not necessarily equate to fire hazard.



all over the apartment before hopefully getting expelled out of
windows. *Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

No. *The standard way of cleaning them is to soak them in hot soapy water
with a good grease-cutting dish detergent, like Ajax or Dawn. *If they're
particulary grungy I scrub them with a Brillo pad.

Jill

On Jan 27, 11:11*am, Amanda Ripanykhazova
wrote:
Thanks for that everyone: This pretty much confirms what I thought, that there isn't much I can do, especially without being able to vent to the exterior from *my interior kitchen! Yes, I do of course realise that proper vents do this and I shouldn't have installed the microwave over the stove but this kitchen is pretty small and I couldn't have installed a REAL vent hood anyway.

The area above the stove must be big enough for the
microwave/vent/light combo unit so it must be big
enough for a decent vent hood too. Not saying you
have room for a big vent hood, but even one
that was the size of the microwave unit, but with a
decent fan and vented
outside would be a huge improvement and probably
do 90%+ of what any hood would do.
I realize venting to the outside can be difficult, but that's
a seperate issue.

Have you looked at what it would take to get a
vent to the outside? Depending on where it's located,
construction, eg which way the joists run, etc it
might not be that hard.





GE says that their newer models (especially the Profile ones) move more air than this Spacemaker XL1400 (400 somethings per minute as opposed to 300) so I wonder whether that would make much difference.

The problem isn't the amount of air being moved. It's
that these are just incapable of FILTERING the air much,
so most of what comes in goes out. Whether that
happens at 400 CFM or 300CFM isn't going to make
much difference. Except that at the higher velocity
the smoke will get distributed faster.


They also say that whereas there probably isn't a charcoal filter in it as standard, I can put one in;

They don't knnow what's in their own product? It should
be right in the spec sheets or user manuals which are available
online.



but it probably wont make much difference to my cooking patterns: I
tend to sear steaks on a (preferably) dirty lined griddle for a minute
or so (on the hotter FORWARD burner!) before sticking the whole thing
in the oven and it is the smoke from that which tends to float all
around the flat. There are indeed two ally filters in there but the
left hand one of them is virtually clean after a year of cooking since
the last cleaning. I cook on the right hand burner. Curiously there is
a griddle in the centre of this PGB918SEM stove but it never struck me
that it would get hot enough to sear steak properly? (it is a bit
heavy and unwieldy to heat up in the oven to 500 degrees and then take
it out, install it on the range and sear from there) Maybe some one
knows whether this griddle could get hot enough, *as more smoke would
probably go straight upwards and be caught in the filter if I cooked
further back on the stove?

FWIW, the ally filters are relatively inexpensive and designed to be replaced rather than cleaned so cleaning is not how they were designed. Meaning that you can put them in the dishwasher but it will dramatically shorten their lives when, after a few cleanings, they start to buckle. I do however remember when someone published a book about hey-presto remedies a few years ago, the author was shown cleaning one of those filters by simply putting it in baking soda or something and it dissolved the grease and it came out completely clean THROUGH AND THROUGH almost immediately just like magic! I have never managed to get it that clean by any sort of washing, whether in a dishwasher or not.

All in all however, I suspect that the dirt build up on the grille-cover over the microwave indicates to me that too much smoke is getting through the ally filter and being expelled straight into the kitchen!! I cant imagine there is a lot I can do about that or that installing charcoal filters would clean THAT air?

I have no idea what an "ally filter" is.