[joe h]

Hello,

This is kind of a stereo question, but I was thinking maybe the r.a.p.
people would have a good idea on this:

I've hooked up some studio powered monitors to a flatscreen TV on the
RCA outs. The sound is great. But I can't adjust the volume with the
TV remote control. The line out sends a static strength signal.

I'm looking for a good one-function box. Something like a receiver
that has two RCA ins, an infrared remote control to adjust the volume,
and then a pair of RCA outs to send the signal to the monitors.

I've looked at what they have in the consumer stores. But those tend
to be all-in-one devices with 700 watts of power etc. Then the hi-fi
stores tend to have purist analog components... good luck finding a
remote control!

The concept is pretty simple. Just looking to have the box with
remote serve as a volume attenuation adjuster via something like a
wireless TV remote.

Looking for good to excellent signal quality where good quality
components are there instead of a zillion features and disappointing
sound quality.

It appears like so much of the remote stuff is going in the direction
of "interconnect your whole house with wireless" or "hook your
computer and ipod up and have it control your whole setup". I'm
looking for a good one-function box: volume up- volume down RCA in/RCA
out with remote control.

Thanks for any ideas.

[Les Cargill[_4_]]

joe h wrote:
Hello,

This is kind of a stereo question, but I was thinking maybe the r.a.p.
people would have a good idea on this:

I've hooked up some studio powered monitors to a flatscreen TV on the
RCA outs. The sound is great. But I can't adjust the volume with the
TV remote control. The line out sends a static strength signal.

I'm looking for a good one-function box. Something like a receiver
that has two RCA ins, an infrared remote control to adjust the volume,
and then a pair of RCA outs to send the signal to the monitors.


So find a Sherwood home stereo receiver that has a remote.

http://www.amazon.com/Sherwood-RX-4105-Stereo-Receiver-Black/dp/B0002EPWC0

I have this one. I can find nothing wrong with it.

snip

Thanks for any ideas.

--
Les Cargill

[Peter Larsen[_3_]]

joe h wrote:

I've hooked up some studio powered monitors to a flatscreen TV on the
RCA outs. The sound is great. But I can't adjust the volume with the
TV remote control. The line out sends a static strength signal.

Often there is also a headphone output, how about that one?

Thanks for any ideas.

Kind regards

Peter Larsen

[Richard Webb[_3_]]

For JOe,

IT doesn't give you wireless remote, but for what else you
may be looking for have a look at the Mackie Big knob, it
might fit the bill for you, even without wireless remote.

I remember I used to own just a preamp with capabilities to
switch between two turntables, two tape decks, and an aux
for driving a regular pro grade power amp. Iirc mine was a
Crown, but I've seen others as well. Surprised somebody
hasn't made one of those with the wireless remote you seek
yet.

But, the home theater market is usually where they want
wireless remote, or as you say, whole house automation, so I think it's a case of "you can't get there from here."

Regards,
Richard
--
| Remove .my.foot for email
| via Waldo's Place USA Fidonet-Internet Gateway Site
| Standard disclaimer: The views of this user are strictly his own.

[William Sommerwerck]

AR (Acoustic Research) used to sell just what you're looking for -- the SRC
Stereo Remote Control. These sometimes show up on eBay.

It has a tape monitor input (to replace the tape monitor it might displace),
and a switched AC outlet (500W) for your system electronics.

It uses a FET attenuator, so there are no active electronics in the signal
path.

[Arny Krueger[_4_]]

"Les Cargill" wrote in message
...
joe h wrote:
Hello,

This is kind of a stereo question, but I was thinking maybe the r.a.p.
people would have a good idea on this:

I've hooked up some studio powered monitors to a flatscreen TV on the
RCA outs. The sound is great. But I can't adjust the volume with the
TV remote control. The line out sends a static strength signal.

I'm looking for a good one-function box. Something like a receiver
that has two RCA ins, an infrared remote control to adjust the volume,
and then a pair of RCA outs to send the signal to the monitors.


So find a Sherwood home stereo receiver that has a remote.

http://www.amazon.com/Sherwood-RX-4105-Stereo-Receiver-Black/dp/B0002EPWC0

I have this one. I can find nothing wrong with it.

Exactly the solution I found years ago. Still works great!

[Arny Krueger[_4_]]

"William Sommerwerck" wrote in message
...
AR (Acoustic Research) used to sell just what you're looking for -- the
SRC
Stereo Remote Control. These sometimes show up on eBay.

It has a tape monitor input (to replace the tape monitor it might
displace),
and a switched AC outlet (500W) for your system electronics.

It uses a FET attenuator, so there are no active electronics in the signal
path.


Actually, there is a buffer amp in the AR SRC.

The absence of active devices does not guarantee linearity. Far from it. The
most linear, highest fidelity audio attenuators out there aside from
straight variable resistors that I know of are loaded with active devices.
And variable resistors are not perfect either. The problem there is
maintaining good frequency response and compatibility with practical cable
lengths and the usual range of impedances involved at line level.

I ran some bench tests on my AR SRC back in the day. I don't remember the
precise numbers, but they were far from wonderful.

FET are a cheap and somewhat dirty solution. If you are serious about
linearity and analog gain control you find a well-engineered VCA.

[William Sommerwerck]

"Arny Krueger" wrote in message
...

"William Sommerwerck" wrote in message
...

AR (Acoustic Research) used to sell just what you're looking for -- the
SRC Stereo Remote Control. These sometimes show up on eBay.

It has a tape monitor input (to replace the tape monitor it might
displace), and a switched AC outlet (500W) for your system electronics.

It uses a FET attenuator, so there are no active electronics in the
signal
path.


Actually, there is a buffer amp in the AR SRC.

The absence of active devices does not guarantee linearity. Far from it.
The most linear, highest fidelity audio attenuators out there aside from
straight variable resistors that I know of are loaded with active devices.
And variable resistors are not perfect either. The problem there is
maintaining good frequency response and compatibility with practical cable
lengths and the usual range of impedances involved at line level.

As I wrote the piece, I thought of the quesiton of manintaining a low output
impedance as the attenuation varied. An op amp at the output would do this
quite nicely.


I ran some bench tests on my AR SRC back in the day. I don't remember
the precise numbers, but they were far from wonderful.

FET are a cheap and somewhat dirty solution. If you are serious about
linearity and analog gain control you find a well-engineered VCA.

I said a FET attenuator, not a FET. There are such packaged devices. As they
work in "bulk" mode, there should be no reason for them to introduce
significant distortion.

RCA made a current-mode op amp that was well-beloved by serious audio
designers. Shure used a bunch of them in its Dolby MP decoders, which were
almost perfectly transparent. Indeed, if the OP found one of these and
switched off the processing (I don't remember if that's possible), it should
work quite nicely.

Of course, if he needs amplification, the Sherwood would be a dirt-cheap
solution.

[Phantom Post]

joe h wrote in news:ed763934-fe39-426c-8a6f-
:

I've hooked up some studio powered monitors to a flatscreen TV on the
RCA outs. The sound is great. But I can't adjust the volume with the
TV remote control. The line out sends a static strength signal.


You've probably looked there already but some TVs, in their audio options
menu, give a choice of whether the audio outs are controlled by the volume
control/remote or not. My Sony has this choice.

--

Pat

email: valid would be net

[joe h]

Thanks Les,

Does that model have line level outputs where the signal strength goes
up and down via the remote control? The problem I have with the TV is
that it sends a generic steady-state signal on the audio line outs,
rather than having the line-out signal strength correspond to the TV
remote control.

These are for powered monitors with either RCA or XLR inputs. They
are looking for a line level signal.

[joe h]

It's a great idea.

Tried it. For some reason, the sound quality is nowhere near as good
as the direct line outs. Defeats a lot of the reason of buying high
quality speakers. That's the only audio output on the line outs that
does go up and down with the remote control. All the others send out
a steady state audio signal that is non-adjustable.

[joe h]

Exactly, Mackie Big Knob, but wireless!

Mackie Big Remote?

My friend's TV does have an audio LR line out that does correspond to
the remote. Why the TV I'm working with has about 20 outputs (and all
of them "dumb" except the inferior headphone outputs) is quite
surprising to me.

[geoff]

Arny Krueger wrote:


Dunno about in the USA, but in Australia and New Zeakand various electronics
hobby outlets put out infrared remote kitsets s with a motor-driven 47K pot.

geoff

[geoff]

William Sommerwerck wrote:

I said a FET attenuator, not a FET. There are such packaged devices.
As they work in "bulk" mode, there should be no reason for them to
introduce significant distortion.

Isn't each individual step effectively an extra active device in the signal
path ?

geoff

[William Sommerwerck]

I said a FET attenuator, not a FET. There are such packaged devices.
As they work in "bulk" mode, there should be no reason for them to
introduce significant distortion.

Isn't each individual step effectively an extra active device in the
signal
path?

No.

Think of a simple two-resistor -- which is what I'm talking about. The FETs
are not used as amplifiers, but as variable resistors.

[William Sommerwerck]

Whoops.

I said a FET attenuator, not a FET. There are such packaged devices.
As they work in "bulk" mode, there should be no reason for them to
introduce significant distortion.

Isn't each individual step effectively an extra active device in the
signal
path?

No.

Think of a simple two-resistor L attenuator -- which is what I'm talking
about.
The FETs are not used as amplifiers, but as variable resistors.

[MarkK]

I said a FET attenuator, not a FET. There are such packaged devices.
As they work in "bulk" mode, there should be no reason for them to
introduce significant distortion.



FETs used as an attenuator DO cause distortion but there is a simple circuit
configuration to cancel most of it. Any decent FET compressor will include
some form of this trick or else operate the FET at a very low level.

http://www.vishay.com/docs/70598/70598.pdf

This is a good demonstration of the fact that audio engineers and
electronics circuit design engineers can learn something from each other.

Mark

[Les Cargill[_4_]]

joe h wrote:
Thanks Les,

Does that model have line level outputs where the signal strength goes
up and down via the remote control?

No, it's a receiver. The speaker outs go up and down.

The problem I have with the TV is
that it sends a generic steady-state signal on the audio line outs,
rather than having the line-out signal strength correspond to the TV
remote control.


Isn't there a headphone out on the TV, then?

These are for powered monitors with either RCA or XLR inputs. They
are looking for a line level signal.

--
Les Cargill

[joe h]

Yes, but it doesn't sound nearly as good as the direct LR line outs
from the TV.

Maybe there is some sort of impedance transformer box that should go
between the headphone outs on the TV and the powered speakers.

[William Sommerwerck]

Yes, but it doesn't sound nearly as good as the direct LR line outs
from the TV.

Maybe there is some sort of impedance transformer box that should go
between the headphone outs on the TV and the powered speakers.

The poorer quality is likely due to a cheap headphone-driver chip.
Regardless, you don't need to change the impedance. A headphone output can
drive just about anything.

[Les Cargill[_4_]]

joe h wrote:
Yes, but it doesn't sound nearly as good as the direct LR line outs
from the TV.

Maybe there is some sort of impedance transformer box that should go
between the headphone outs on the TV and the powered speakers.

It's probably just a crappy output. They'll most likely be voltage
coupled, so Z doesn't matter.

--
Les Cargill

[geoff]

William Sommerwerck wrote:
I said a FET attenuator, not a FET. There are such packaged devices.
As they work in "bulk" mode, there should be no reason for them to
introduce significant distortion.

Isn't each individual step effectively an extra active device in the
signal path?

No.

Think of a simple two-resistor -- which is what I'm talking about.
The FETs are not used as amplifiers, but as variable resistors.

And each 'variable resitor', or fixed one for that matter, is not carbon or
metal oxide, but silicon.

geoff

[Arny Krueger[_4_]]

"joe h" wrote in message
...

It's a great idea.

Not only that, but it works like a charm if you implement it well.

Tried it. For some reason, the sound quality is nowhere near as good
as the direct line outs.

Please provide a more detailed explanation of what you did.

Defeats a lot of the reason of buying high quality speakers.

How?

[Arny Krueger[_4_]]

"William Sommerwerck" wrote in message
...
"Arny Krueger" wrote in message
...

"William Sommerwerck" wrote in message
...

AR (Acoustic Research) used to sell just what you're looking for -- the
SRC Stereo Remote Control. These sometimes show up on eBay.

It has a tape monitor input (to replace the tape monitor it might
displace), and a switched AC outlet (500W) for your system electronics.

It uses a FET attenuator, so there are no active electronics in the
signal
path.


Actually, there is a buffer amp in the AR SRC.

The absence of active devices does not guarantee linearity. Far from it.
The most linear, highest fidelity audio attenuators out there aside from
straight variable resistors that I know of are loaded with active
devices.
And variable resistors are not perfect either. The problem there is
maintaining good frequency response and compatibility with practical
cable
lengths and the usual range of impedances involved at line level.

As I wrote the piece, I thought of the quesiton of manintaining a low
output
impedance as the attenuation varied. An op amp at the output would do this
quite nicely.

If memorys serves, thats what the AR SRC does it has an op amp output
buffer.

I ran some bench tests on my AR SRC back in the day. I don't remember
the precise numbers, but they were far from wonderful.

FET are a cheap and somewhat dirty solution. If you are serious about
linearity and analog gain control you find a well-engineered VCA.

I said a FET attenuator, not a FET.

You are missing the obvious - what is the attenuation component of a FET
attenuator?

The AR SRC generated a a fair amount of nonlinear distortion by the
standards of similar commercial devices such as high quality audio
preamplifiers.

When highly linear analog gain control is desired in a professional audio
gear (e.g. consoles, compressors, expanders), the tool of choice is a high
quality VCA.

There are such packaged devices. As they
work in "bulk" mode, there should be no reason for them to introduce
significant distortion.

Depends what you call signficant. If there was no reason for FETs to
generate distortion then equipment based on FETs would have inherently low
distortion. In actual practice, FET are competitive with other active
devices, some better some worse. For example, FET based audio gear has
never become the clearly dominant approach, whether power amps or preamps.
Ditto for audio op amps. More traditional and non-traditional use of bipolar
devices rule, which is not to say that FETs have totally gone away.


RCA made a current-mode op amp that was well-beloved by serious audio
designers. Shure used a bunch of them in its Dolby MP decoders, which were
almost perfectly transparent. Indeed, if the OP found one of these and
switched off the processing (I don't remember if that's possible), it
should
work quite nicely.

I believe that by "current mode op amp" you mean a transconductance op amp,
which is a well-known means for implementing a fairly analog linear gain
control.

Of course, if he needs amplification, the Sherwood would be a dirt-cheap
solution.

Not only is it dirt cheap, but it is surprisingly clean and powerful.

[Scott Dorsey]

joe h wrote:

I'm looking for a good one-function box. Something like a receiver
that has two RCA ins, an infrared remote control to adjust the volume,
and then a pair of RCA outs to send the signal to the monitors.

I seem to think that Parts Express had such a thing in their catalogue at
some point.

The next step up would be an industrial A/V remote level device, like an
Extron or Crestron, which would be more money but might outlast the TV.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[MarkK]

Depends what you call signficant. If there was no reason for FETs to
generate distortion then equipment based on FETs would have inherently low
distortion. In actual practice, FET are competitive with other active
devices, some better some worse. For example, FET based audio gear has
never become the clearly dominant approach, whether power amps or preamps.
Ditto for audio op amps. More traditional and non-traditional use of
bipolar
devices rule, which is not to say that FETs have totally gone away.



Besides the distortion (which is easily improved per my previous post) FETs
as VCAs also suffer from the fact that it is difficult to make multiple
channels tack one another due to the wide variation of gate characteristic
from part to part.

This is not an issue in mono compressors but is an issue in almost every
other application.

[geoff]

MarkK wrote:
Depends what you call signficant. If there was no reason for FETs to
generate distortion then equipment based on FETs would have
inherently low distortion. In actual practice, FET are competitive
with other active devices, some better some worse. For example, FET
based audio gear has never become the clearly dominant approach,
whether power amps or preamps. Ditto for audio op amps. More
traditional and non-traditional use of bipolar devices rule, which
is not to say that FETs have totally gone away.



Besides the distortion (which is easily improved per my previous
post) FETs as VCAs also suffer from the fact that it is difficult to
make multiple channels tack one another due to the wide variation of
gate characteristic from part to part.

This is not an issue in mono compressors but is an issue in almost
every other application.

And that gates on FETs are invariably high impedence. Of course not an
issue when used as switches, but the conducting section remains
semiconductor material.

geoff

[Chuck[_10_]]

On 7 Nov 2011 10:32:12 -0500, (Scott Dorsey) wrote:

joe h wrote:

I'm looking for a good one-function box. Something like a receiver
that has two RCA ins, an infrared remote control to adjust the volume,
and then a pair of RCA outs to send the signal to the monitors.

I seem to think that Parts Express had such a thing in their catalogue at
some point.

The next step up would be an industrial A/V remote level device, like an
Extron or Crestron, which would be more money but might outlast the TV.
--scott


A company named Chase made a remote controlled volume control/switcher
about 20 years ago. One might turn up on EBay.

[Carey Carlan]

joe h wrote in news:841c5b15-d6f9-4557-b718-
:

Exactly, Mackie Big Knob, but wireless!

Mackie Big Remote?

My friend's TV does have an audio LR line out that does correspond to
the remote. Why the TV I'm working with has about 20 outputs (and all
of them "dumb" except the inferior headphone outputs) is quite
surprising to me.

You could get a radio controlled servo at the hobby shop and use it to spin
the Big Knob...