Having a bit of a change around during the hols, and I need to link up a
computer (Mac Mini) to a USB DAC 5 metres away. I've tried it with a 5m
extension plus a 1m A-B cable, and it works, but the music cuts out from
time to time. Actually, seems fine for the last few hours, but I need an
extension cable anyway.

I would just buy a 5m cable and be done, but ebay sellers are pushing
something called 'active repeater extension cables' for about 5 quid
extra. I can't seem to find anything about them - should I spend the
extra five quid on such a thing?

Unrelated, I've just noticed that I can change the volume of the music
using an iPod Touch remote application through the Mac - on the optical
output and the USB. How does this work with digital?!

Thanks, Rob

"Rob" wrote in message


Having a bit of a change around during the hols, and I
need to link up a computer (Mac Mini) to a USB DAC 5
metres away.

The usual length limit for USB is 15 feet - close enough to 5 meters.

I've tried it with a 5m extension plus a 1m
A-B cable, and it works, but the music cuts out from time
to time. Actually, seems fine for the last few hours, but
I need an extension cable anyway.

A little slack never hurts.

I would just buy a 5m cable and be done, but ebay sellers
are pushing something called 'active repeater extension
cables' for about 5 quid extra. I can't seem to find
anything about them - should I spend the extra five quid
on such a thing?

The safe position is the active cable since you're really over the edge.

Arny Krueger wrote:
"Rob" wrote in message


Having a bit of a change around during the hols, and I
need to link up a computer (Mac Mini) to a USB DAC 5
metres away.

The usual length limit for USB is 15 feet - close enough to 5 meters.

I've tried it with a 5m extension plus a 1m
A-B cable, and it works, but the music cuts out from time
to time. Actually, seems fine for the last few hours, but
I need an extension cable anyway.

A little slack never hurts.

I would just buy a 5m cable and be done, but ebay sellers
are pushing something called 'active repeater extension
cables' for about 5 quid extra. I can't seem to find
anything about them - should I spend the extra five quid
on such a thing?

The safe position is the active cable since you're really over the edge.


Yes, thanks, agreed. I wasn't sure how they work - there doesn't seem to
be any power supply, yet the claim is 25m. Thought it might be some kind
of scam.

Rob

Rob wrote:
Active USB extensions

Yes, thanks, agreed. I wasn't sure how they work - there doesn't seem to
be any power supply, yet the claim is 25m. Thought it might be some kind
of scam.

There's power available on the USB connection. Up to 500mA at 5 Volts.
The line driver and pulse reshaping circuitry isn't all that power
hungry, and can fit in a slightly oversize USB line socket.

--
Tciao for Now!

John.

"Rob" wrote in message

Arny Krueger wrote:
"Rob" wrote in message


Having a bit of a change around during the hols, and I
need to link up a computer (Mac Mini) to a USB DAC 5
metres away.

The usual length limit for USB is 15 feet - close enough
to 5 meters.
I've tried it with a 5m extension plus a 1m
A-B cable, and it works, but the music cuts out from
time to time. Actually, seems fine for the last few
hours, but I need an extension cable anyway.

A little slack never hurts.

I would just buy a 5m cable and be done, but ebay
sellers are pushing something called 'active repeater
extension cables' for about 5 quid extra. I can't seem
to find anything about them - should I spend the extra
five quid on such a thing?

The safe position is the active cable since you're
really over the edge.

Yes, thanks, agreed. I wasn't sure how they work - there
doesn't seem to be any power supply, yet the claim is
25m. Thought it might be some kind of scam.

USB includes 5 volt power as part of the cable design. That's why many
products that plug into USB ports need have no other source of power. Ditto
for HDMI.

Arny Krueger wrote:
"Rob" wrote in message

Arny Krueger wrote:
"Rob" wrote in message


Having a bit of a change around during the hols, and I
need to link up a computer (Mac Mini) to a USB DAC 5
metres away.
The usual length limit for USB is 15 feet - close enough
to 5 meters.
I've tried it with a 5m extension plus a 1m
A-B cable, and it works, but the music cuts out from
time to time. Actually, seems fine for the last few
hours, but I need an extension cable anyway.
A little slack never hurts.

I would just buy a 5m cable and be done, but ebay
sellers are pushing something called 'active repeater
extension cables' for about 5 quid extra. I can't seem
to find anything about them - should I spend the extra
five quid on such a thing?
The safe position is the active cable since you're
really over the edge.
Yes, thanks, agreed. I wasn't sure how they work - there
doesn't seem to be any power supply, yet the claim is
25m. Thought it might be some kind of scam.

USB includes 5 volt power as part of the cable design. That's why many
products that plug into USB ports need have no other source of power. Ditto
for HDMI.


Ah right - I see, thanks. And only 5mA draw, very clever.

Rob

Rob wrote:

Yes, thanks, agreed. I wasn't sure how they work - there doesn't seem
to be any power supply, yet the claim is 25m. Thought it might be
some kind of scam.


Like the rest have said, they work fine. I have used several "in series" to
control a telescope some 80 feet from my PC.

Arny Krueger wrote:
"Rob" wrote in message


Having a bit of a change around during the hols, and I
need to link up a computer (Mac Mini) to a USB DAC 5
metres away.

The usual length limit for USB is 15 feet - close enough to 5 meters.

The maximum length for USB1.1 devices is 3 metres. My USB DAC is a
USB1.1 device and not USB2. Whether the cable limit refers to the host
adaptor or the client device I don't know.

Anton Gÿsen wrote:
Arny Krueger wrote:
"Rob" wrote in message


Having a bit of a change around during the hols, and I
need to link up a computer (Mac Mini) to a USB DAC 5
metres away.

The usual length limit for USB is 15 feet - close enough to 5 meters.

The maximum length for USB1.1 devices is 3 metres. My USB DAC is a
USB1.1 device and not USB2. Whether the cable limit refers to the host
adaptor or the client device I don't know.

It's the maximum total length of unboosted cable permitted between the
master and slave devices before the signal needs regenerating. You can
daisy chain a number of 3 metre segments, provided they are all linked
by active connectors, but the active connectors in the chain must be
there, and no more than the maximum permitted distance apart.

Example:-

PC (Master) --- 3metres --- Active connector --- 3metres ---- DAC (Slave
device)

Should work

PC (Master)--- 6 metres --- DAC (Slave device)

Probably won't.

--
Tciao for Now!

John.

John Williamson wrote:
Anton Gÿsen wrote:
Arny Krueger wrote:
"Rob" wrote in message


Having a bit of a change around during the hols, and I
need to link up a computer (Mac Mini) to a USB DAC 5
metres away.

The usual length limit for USB is 15 feet - close enough to 5 meters.

The maximum length for USB1.1 devices is 3 metres. My USB DAC is a
USB1.1 device and not USB2. Whether the cable limit refers to the host
adaptor or the client device I don't know.

It's the maximum total length of unboosted cable permitted between the
master and slave devices before the signal needs regenerating. You can
daisy chain a number of 3 metre segments, provided they are all linked
by active connectors, but the active connectors in the chain must be
there, and no more than the maximum permitted distance apart.

Example:-

PC (Master) --- 3metres --- Active connector --- 3metres ---- DAC (Slave
device)

Should work

PC (Master)--- 6 metres --- DAC (Slave device)

Probably won't.

But would

PC (Master - USB 2.0 hub)--- 5 metres --- DAC (USB 1.1 Slave device)

work? Not that it really matters.