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Active Preamplifiers - Improving a weak link?

I tried a Glasshouse TVC and I base my opinion on what it did in my system. I liked its transparency buy not its restrained dynamics and occasional restlessness. The grounded grid I use gives me added life, balls and a pleasing 3D aspect, especially since the DACT attenuator replaced the ALPS Blue pot.
 
.... Does it follow that a further improvement could be had by completely removing the volume pot from an active preamp, connecting the preamp output to a passive TVC?

Possibly a daft idea but I'd like to open it up for discussion.

It's all system dependent!!!

One likely benefit of a TVC is that it breaks ground loops and another is that it limits the bandwidth. My view is that in a correctly designed and implemented system an Alps Blue will give better audible and measured performance than a TVC and at much lower cost.
 
It's all system dependent!!!

One likely benefit of a TVC is that it breaks ground loops and another is that it limits the bandwidth. My view is that in a correctly designed and implemented system an Alps Blue will give better audible and measured performance than a TVC and at much lower cost.
Thanks.

My Ella valve amplifier from diy hifi supply was supplied with an Alps Blue, I can't see what I might change in the implementation that would result in it improving on the other options I've lived with...the TKD, the DACT and the TVC.

I'm only interested in the audible performance by the way. I wouldn't switch back to the Alps Blue (I still have that too) no matter how much better it measures than the other options.

Edit: If anyone has a diy hifi supply "Basie" they don't want I may be interested in trying all this out if the price is reasonable. :)
 
I'm only interested in the audible performance by the way. I wouldn't switch back to the Alps Blue (I still have that too) no matter how much better it measures than the other options.

If you are going to compare passive solutions you need to know both the drive and load conditions. Both determine what works well and what flops.

So an Alps Blue could easily work superbly in one circuit but be a disaster in another. Plus there are many versions, so a 50k Blue might work well and a 20k less well.
 
If you are going to compare passive solutions you need to know both the drive and load conditions. Both determine what works well and what flops.

So an Alps Blue could easily work superbly in one circuit but be a disaster in another. Plus there are many versions, so a 50k Blue might work well and a 20k less well.
Yes, I'm aware of that, however I'm not specifically comparing passive solutions. I'm talking about whether there may be any benefit to adding an active preamplifier to my system, removing the volume pot and using it along with a passive TVC.
 
A TVC with an active unity gain buffer at each end?

No benefit at all.
Transformers add distortion, pots don't.

Martin gave the definitive answer in post 2.
 
I've just had a dastardly clever idea. A very useful 'tone control' would be one that compensates for baffle step. It would both cut or boost the LF with selectable F3 frequencies, hence accommodating a wide range of loudspeakers in a wide range of room configurations. Imagine, SBLs and Kans no longer need to be wall mounted and meaty american behemoths can be installed in puny British rooms with impunity.

Oh wait, isn't that how the parametric EQ works in Quad preamps?
 
A TVC with an active unity gain buffer at each end?

No benefit at all.
Transformers add distortion, pots don't.

Martin gave the definitive answer in post 2.
Right, so let's go backwards and keep in mind I'm not remotely interested in how things measure, just how they sound.

If I remove the Django TVC and replace it with (for example) a Basie active preamplifier complete with Alps Blue volume pot my system will sound like 'x'.

If I swap the Alps Blue in the Basie for a TKD volume pot and then for a DACT stepped attenuator it will sound different with each one, let's say it will sound like 'y' and 'z'. Whichever of 'x', 'y' and 'z' sounds the best is down to personal preference but they will all work.

Are you saying that removing all of these volume controls and connecting the output of the Basie directly to the TVC is fundamentally a bad thing that can't sound good, even though the TVC currently sounds better than them all in my current setup?

Thanks in advance.
 
Brian,
I have a creek obh-22 which is an alps blue based remote control passive. i added a B4 amplifier as a buffer and it sounded better to my ears. i also did the same with a naim 32.5. (This worked OK actually and gave a reasonable result......) the naim 32.5 wasn't as good a buffer as the B4.

I therefore completed my b4 project adding a remote control alps blue and input control to make an excellent preamplifier. The b4 is a buffer and adds no gain.

I am going to try a relay based volume control to compare things with the alps b4. This, if working well will become my main preamp or a headphone amp.
 


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