Is dist amp useful for single source? Before/after TBC?

[mbassiouny]

Hi,

I know that a dist amp takes 1 input signal and provides this same signal to multiple outputs without loss.

But is it a good idea to use a dist amp device such as VP-299 for just 1 single output? Will it do more harm than good?

I tried VCR->capture card directly VS vcr>VP299> capture card and visually I noticed it made the colors slightly darker and amplified some visual details but not sure if it does any harm I am not aware of.

Also where does a dist amp sit if used with a TBC such as AVT/ctb-100?

Is it VCR>vp-299>tbc>capture card on pc
Or Is it VCR>tbc>vp-299>capture card on pc

[latreche34]

It looks like it is already doing damage, What is your motive for using it anyway?

[cygnals]

If you're not sure why you're using it, please don't use it.

[lordsmurf]

If the amp has bad caps, it's not "no loss". But even without bad caps, it's not 100% transparent.

Distribution amps are final in a workflow chain, just prior to ingest. But if you're not capturing to multiple ingest, zero reason to use it. I'd actually say there's no reason, period, with a modern digital workflow.

[mbassiouny]

My motive is to obtain the best possible quality for my captures.

Quote:

It looks like it is already doing damage

as I already mentioned, it already amplified some visual details that were not noticeable before using it, so I personally don't see the harm in this...

What I am trying to figure is: is dist amp someth that should be used if and only if you require to have multiple signals, or could it have other benefits.

For example The datavideo TBC-1000 is TBC-100+VP-299, but a lot of people use it for the TBC function mainly, does that mean they get some harm when using that dist amp but they are forced to accept it? or is it still somehow useful?

Quote:

If you're not sure why you're using it, please don't use it.

Then instead of telling not to use it, could you please explain when to use it I opened the thread to ask and learn

Edit: oops, @lordsmurf I answered before seeing your reply. Do you mind having a look on the captures and enlighten me on why the one with the vp-299 looks better? is what I consider visually "better" actually a defect/harm?

[lordsmurf]

A VP-299 is for splitting video.

Examples:
- play 1 DVD player to 4 TVs, for an all-side display standard fed from DVD player on a loop
- play 1 live signal to 4 DVD recorders (each is then a master, copy duplicate from those 4 masters, such as HS band videos in the 2000s, as sold by on-site video companies)

These have to place in a standard videotape-to-digital workflow.

VP-299 is not a TBC, or anything else.

That fact that VP-299 is part of a TBC-1000 is inconsequential. It's being used for the TBC-100 inside, not the VP-299. You'll only use 1 output. And it's ideal to bypass the audio. In fact, some members here have successfully bypassed the VP-299 entirely, by modding the already-modded VP-301x (TBC-100) card. The TBC-1000 is almost never a stock TBC-100, but modded. In fact, the VP-299 inside the TBC0-1000 is also almost always modded. You usually cannot take a plain VP-299 and TBC-100, and simply make a TBC-1000. Effort required, in-depth knowledge of these devices required.

[cygnals]

The only reason to use a distribution amp is if you need a distribution amp. If you don't need what a distribution amp does -- pass a signal on to more than one device at the same time -- then don't use it.

If such a function is soldered into a piece of gear you're using for another reason, that's one thing.

But imagine something simpler like copying audio -- you wouldn't add a Y-splitter cable to your other cable just because you have one. You'd only add that if you needed a cable to split the signal. Otherwise it's just something that could make the signal worse.

[mbassiouny]

@cygnals, thx a lot for the explanation. I appreciate the clarity


@lordsmurf, Thanks for taking the time to write a detailed answer.

Quote:

If such a function is soldered into a piece of gear you're using for another reason, that's one thing.

Yes, I get it from LS's answer. It is something that users accept, but not necessarily considered an extra advantage.



I understand your point guys, I am fully aware Dist amp is not TBC, and it has a job: split signal to multiple destinations, if you don't need that job, there is no reason to use.

But I think I am still not able to make you guys understand my main point/my question.
The reason I am asking if it is useful for 1 output it's because I see a visual improvement on my side when I use it.

I have attached 2 samples (videos this time, not 2 pictures like the ones I attached in my previous post).

Can someone please explain to me why is the robot thing on the left much clearer with the VP-299 (see photos in my previous post for the specific frame I am talking about) if the device is supposed to offer no benefit over direct capture from the VCR?

[mbassiouny]

Quote:

But I think I am still not able to make you guys understand my main point/my question.
The reason I am asking if it is useful for 1 output it's because I see a visual improvement on my side when I use it.

Actually another question (or maybe the same question phrased differently) : does a dist amp include a proc amp? if not how does it achieve the amplification?

The way I see this : the signal is spitted but before the splitting, the signal is amplified, isn't this same role of a proc amp that amplifies the signal? or is it a different type of amplification than what a normal procAmp does?

Does that mean a proc amp is dist amp that does not distribute/split the signal and vice-versa?

[traal]

Your "without-amp.png" appears to have blown highlights, and the amp restored them by darkening the whole image. You don't need a distribution amplifier to do that, just adjust the proc amp settings in your capture card before capture to get a good histogram. http://www.digitalfaq.com/forum/vide...-settings.html

[lordsmurf]

Distribution (dist, distro) amplifier (amp) has no relation to processing (proc) amp. None.

[mbassiouny]

Thanks @traal and @lordsmurf.

both your replies together answer the (2 parts of my) question and cleared it up for me