It's alive!

[Gerry E.]

Hi:

I'm close to pulling the trigger but I have a couple of questions:

1. Here's a sentence from the product description: "We give you three inputs, one of which can be reconfigured from the stock RCA jack to an XLR jack that can be combined with the soon to be offered balanced input transformers."  What does a balanced input transformer actually do?  Does it have something to do with pseudo-balanced vs. true balanced?

2. Not to open up the proverbial "can-o-worms" but what are the advantages of an active preamp?  I'm currently using a remote controlled LDR passive preamp with my Paramounts.  I'm more than willing to give up remote volume control for better sound quality.  However, there's one argument against an active preamp that I can't ignore.  It goes something like this "Why amplify the signal when you are just going to throw it away at the volume control?"

My system has plenty of gain and ideal impedance matches, so the passive preamp works extremely well.  However, there must be more to it.  That's what I'm trying to find out.  Thanks.

Gerry

P.S. I understand that Active vs. Passive is one of those Audio topics right up there with Analog vs. Digital, Tube vs. Solid State, etc.

 

[earwaxxer]

Hey Gerry -

I can relate to the 'active vs. passive' debate. I was a preamp 'non-believer' for years until I had the chance to try a tube preamp for practically nothing (Quickie).

Lets just say, I'm a believer now (and I couldn't leave her if I tried..). What the active pre did for my system was bring the music to life. Hard to describe, but the music was definitely more like 'music'. Dynamic, flesh on bones, exciting, more engaging, bigger etc. I can use my Transporter as a preamp, and I have other integrated amps that I have experimented with. I keep going back to the tube preamp. Of course the rest of my system is solid state. YMMV for sure, but its worth a go!

 

[Grainger49]

Gerry,

I'm not familiar with the LDR passive pre.  But... with an active preamp the sources "see" a fittingly high impedance and it presents a proper low impedance to the amplifier.

That is an advantage over many, but not all, passive preamps.

 

[Paul Birkeland]

Here's a sentence from the product description: "We give you three inputs, one of which can be reconfigured from the stock RCA jack to an XLR jack that can be combined with the soon to be offered balanced input transformers."  What does a balanced input transformer actually do?  Does it have something to do with pseudo-balanced vs. true balanced?

The balanced input transformer lets the input float, relieving ground loops and reducing noise (potentially).  This is a true balanced input, not pseudo balanced. 

It's also worth mentioning that you could dump the balanced output and run single ended only quite easily.

-PB

 

[Paul Joppa]

I have never seen, and still do not see, any technical reason why an active preamp should be of any use in a system that already has adequate gain. I also know that far too many people with excellent ears say just what earwaxxer said. I myself certainly love the BeePre sound in Doc B's big reference system, and I have heard that system with a passive (not recently enough to have confidence in my judgement though). You cannot ignore subjective reality just because you don't have a technical reason to believe it. Do more listening to more systems, and make up your own mind! I'll be doing that (replacing my Extended Foreplay) eventually.

 

[jrebman]

Congrats BH crew!  I'd say I'd be looking to get one, but that would be a bit silly given my other project in progress .  Though I do still see this as an eventual addition to the herd here.  Paramounts as well.

-- Jim

 

[jrebman]

Oh well, I'm in!

Question for the BH guys -- will this fit on a shelf with a 10" clearance between shelves? -- not absolutely critical, but would be somewhat more convenient.  Though I suppose that will depend a lot on the tubes used -- but say sophias /TJs?  I can alsmost guarantee that the humongous EMLs won't.

Thanks,

Jim

 

[dht 4 me]

I have never seen, and still do not see, any technical reason why an active preamp should be of any use in a system that already has adequate gain. I also know that far too many people with excellent ears say just what earwaxxer said. I myself certainly love the BeePre sound in Doc B's big reference system, and I have heard that system with a passive (not recently enough to have confidence in my judgement though). You cannot ignore subjective reality just because you don't have a technical reason to believe it. Do more listening to more systems, and make up your own mind! I'll be doing that (replacing my Extended Foreplay) eventually.

The ability to source more current, have more headroom and (with digital) the added HF isolation surely carries zero weight with the spec - tech crowd.
Even better is who would want antique tubes and vinatge superbly executed technology with DHT's.

I absolutely have to remember Paul's "Subjective reality" quote as it is the most eloquent depiction I have yet to hear.

There is nothing like the speed, air and imaging of a DHT. Doc is offering the palette of Sakuma's wine or the price of Sake here folks.

 

[Doc B]

Hey stranger! Good to see you around here. Your preamp did a lot to lean me toward the DHT preamp idea a few years ago. I think before yours every one I heard was so hummy that I couldn't grok the benefits. Hearing yours vs. a FPIII was a real ear opener.

 

[4krow]

DHT,    That is a beautiful pre-amp you have there.

  Guys, you have said it correctly. It didn't make sense to me to have any equipment between the source and power amp if not needed, UNTIL I used a buffered stage. Then, I never went back. Of course a volume control needs to be implemented.

 

[Chris]

Oh Man! ... that is a beauty!!... I cannot wait to get myself one... is that Koa wood on the side cheeks?

 

[Doc B]

This is getting OT, but I just found out that dht4me has opened a new gallery with two other hugely talented photographers in the Palazzo in Las Vegas. It looks incredible:

http://www.youtube.com/watch?v=vXj5XXZrmek

http://www.natural-wonders-gallery.com/#/Welcome/

 

[Chris]

it sure does... LOVE the tropical fish and the horses!...

 

[Frihed89]

230/240VAC/50 Hz?

Dual volume controls?

 

[Paul Birkeland]

230/240VAC/50 Hz?

Dual volume controls?

Yes, we do have 240V iron that will handle 50 or 60 Hz available.

The stock circuit has a volume and balance control, and there will be an upgrade option that is a coarse and fine stepped attenuator. 

-PB

 

[Frihed89]

But NOT left and right channel volume?

 

[Paul Birkeland]

But NOT left and right channel volume?

No, but there is a way in the upgrade to trim each channel if you wanted.

You could also buy a pair of mono 24 step attenuators and use those if the independent volume controls are a big priority.

In my own experience, I find that two controls with lots of steps can get a bit annoying, as getting both controls on the same stop gets increasingly difficult.

 

[4krow]

Actually, that is a good point. The last Ceegar box I made had 66 steps for each channel! The pointer knobs helped. I built it as a buffer amp and so you could find the volume you wanted, and send it to the integrated amp to get the right amount of 'dial' for the master volume. In my latest iteration of this project, I have chosen a stereo volume control with stepped attenuators for L/R channels. This way only 36 steps, and easier by way of the stereo(master) volume.

 

[Paul Birkeland]

But NOT left and right channel volume?

You know, there is a way with the stepped attenuator to have a coarse stereo attenuator and dual mono fine controls.

To make this happen, you would need to be a little handy with fabrication, and you'd have to drill new holes for and move the input selector elsewhere.

I did get this upgrade attenuator installed today, and Doc B. was floored by the results, as was I.  I haven't heard a volume control make this kind of difference, ever!

 

[jrebman]

PB,

Is this the same one that's in my pre?

Just a little confused about all the various attenuator options that have been talked about here over the past several months.

-- Jim