So let’s talk about Active, Passive, and TVC / AVC preamps
Where did you get that remote?
I could probably get the guy that made mine to make you one. I think he has 9 boards left to build the remote TVCs with. It has 2 inputs and you can switch between them on the fly by remote.
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Pioneerhip
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Super nice! I have the same remote for my 26 preamp. It oooozes class. I love it!
One thing that the AVC does really well over other preamps I've had is that it's fantastic for low-level listening. It doesn't sound thin or hollow, its all there even at a whisper. Which, again, was a surprise as I had a passive before, a McCormack TLC-1 deluxe, that was only really good at volume (and even then, it only bested its contemporaries and older in the preamp world... newer active preamps like the Primare did everything it did as far as transparency, but beat it up rather dramatically in dynamics). The TLC was a resistor-based passive and the comparison between it and the Slagleformer-Redboy creation was a bit lesson in avoiding lumping things into broad camps. All passives aren't the same.
Dang, just looked up the Icon balance Slagle pre...pricey! I agree with this statement in the ad about it , if it sounds like the similar unbalanced one I have...."No frills, looks funny in multi-kilobuck systems, but it is the real deal and extremely elegant to use."
Pioneerhip
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it would look right at home in my NON multi-kilobuck system
Pioneerhip
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I see most including mine have the 6db gain switch. Can someone explain how it works?
asilker
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John I think this is an interesting philosophy. I have not agreed with this, but maybe I need to listen around more.
I would love to hear what you think of my current setup, especially in terms of constructive criticism. My dac is running a low pass filter which doubles as the preamplifier (more or less), and that runs straight into a Firstwatt F5 - and I think I have the room set up pretty well in terms of placement and acoustic treatment. But I am thinking about building up a new DIY rig over the winter, so an outside opinion could provide some direction.
The S&B transformers have a split primary (input side) winding. The switch allows the user to select between the full winding or half the primary winding, resulting in a different turns ratio and a different gain structure -- in this case, +6dB.
The general consensus is that using only half the primary is... sloppy. Yes, you get a bit more gain but it doesn't sound as good.
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asilker
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Genuine question: do you mind elaborating on "sloppy"? Is this an issue of design elegance and the problem of having half the primary in the breeze, or is this an engineering problem?
Probably the former... I wouldn't think of it as an engineering problem. In fact, the transformers were specifically designed with a split primary to offer the +6dB voltage gain option. It's clever... but not entirely necessary, I'd argue.
TVC stands for Transformer Volume Control, which is a better description than "passive preamplifier" for this device. The idea is that your source component -- whether it's a CDP or DAC or phono preamp -- is already providing enough voltage to fully drive your amplifier(s) so all you need to do is attenuate (control) that voltage and resultant volume... no "amplification" is necessary, here.
If you're using the full winding on the primary, the secondary winding neatly steps the source voltage down... But it feels weird to try to "step up" on the primary with a +6dB gain, only to step down on the secondary.
I prefer the sound of the unity gain (full winding). At least one reviewer out there preferred the sound of the +6dB, so hey... De gustibus and all that.
I guess I'm saying I wouldn't make a buying decision on the +6dB option alone. It's a cheap party trick, in my opinion.
Pioneerhip
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Probably the former... I wouldn't think of it as an engineering problem. In fact, the transformers were specifically designed with a split primary to offer the +6dB voltage gain option. It's clever... but not entirely necessary, I'd argue.
TVC stands for Transformer Volume Control, which is a better description than "passive preamplifier" for this device. The idea is that your source component -- whether it's a CDP or DAC or phono preamp -- is already providing enough voltage to fully drive your amplifier(s) so all you need to do is attenuate (control) that voltage and resultant volume... no "amplification" is necessary, here.
If you're using the full winding on the primary, the secondary winding neatly steps the source voltage down... But it feels weird to try to "step up" on the primary with a +6dB gain, only to step down on the secondary.
I prefer the sound of the unity gain (full winding). At least one reviewer out there preferred the sound of the +6dB, so hey... De gustibus and all that.
I guess I'm saying I wouldn't make a buying decision on the +6dB option alone. It's a cheap party trick, in my opinion.
I havent even flipped the switch as it's not needed with my amp. I guess if I had an amp that needed a little gain it might nice to have.
ICTWoody
No longer a junior member
I mean… I do have a Silver AVC-1 and I’ve been considering going active. I bought it because @Redboy made me and I’ve been very happy with it. But I mean… everything has its price.
I want to check if I could get the preamp I want and I could be maybe convinced to relinquish it… but man, it could be a move I regret. It just… works.
- Woody
Very nice set up, as always!👏🏻 😊
Pioneerhip
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I'd be happy to help out. I know we were making plans to meet up then my work went nuts, then I went on vacation. I could bring a pre or two over if that would be of any interest?
I've tried running both of my DACs as preamps and everything has fallen apart. I've found the preamps are kind of the glue that holds everything together, eeks the music out of the sound. This isn't to say I think that preamps are the only thing that matters, just that they have tended to be what makes me like or dislike my systems once the other pieces are all there. I certainly could break it with speakers, too, or anything else.
Pioneerhip
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I tried running my Lumin as a preamp. It sounds good, and it might be in my head, but I always feel like it isn't up to the task. It has the LEEDS volume control that isn't supposed to affect the signal, but I can clearly hear it.
When I ran both my Berkeley Alpha and Topping D70 straight into my amp, the sound was detailed but flat, two dimensional. I didn't like it at all. Why that was the case, I have no idea. I don't know what kind of volume control either had. When run line level the Topping wants to be maxed out and the Berkeley a bit down from max, according to the manual. Either way, I have analog sources as well so neither could be a long-term preamp even if they worked that way.
A friend of mine has a Weiss DAC and runs it as a preamp, and he says its incredible that way. So, anyway, I'm not assuming this is an across the board thing. Most things aren't.
