Not ENOUGH GAIN


I have a transcendent grounded grid preamp,hooked up to a anthem a2 power amp 225 watts per,a pair of von schweikert vr3,I have very little gain,I will have the volume turned up to seven and it is just at a normal level. Is there any way I can increase volume. THanks Maxwell
maxwell
I will ask you the obvious, is the preamp new to the system? Have had any other preamps prior to this one hooked up to the Anthem? I find it difficult to velieve that the Anthem has'nt got enough gain. Also I own VR2 speakers, and drove them comfortably with 40 watt and 60 watt tube amps. What is the sensivity of the VR3s?
The Transcendent grounded grid preamp uses 12au7's (gain of 20) at all stages, one of the lowest gain tubes in the 12??7 range.
You could change the input tube first for a 12at7 ( gain of 60)and see how you go. These 12at7's are interchangable with the 12au7 as are 12ay7's (gain of 40).

Cheers George
Your Anthem A2 is spec'd at 29db gain, with input sensitivity of 1.5v. The Grounded Grid preamp is spec'd at 12db gain, so you have a combined preamp/amp gain of 41db -- if anything, a bit on the high side. And the von Schweikert VR3 are 87db/w/m efficient. The only way you can have a problem is if your source has unusually low output (considerabily lower than the normal 2V out on CD players), or if there is a gain constriction in either your preamp or the input stage of your power amp, or your power amp output stage is not fully functioning, or there is something unusually wrong in the speaker crossover dramatically sucking power. Or the preamp has an unusually shallow taper. You're not lacking gain -- if anything you have surplus gain to scrub off.

Phil
Mechans,Yes the pre is new to the system,I have had many different preamps in my systems like counterpoint,audio research,thershold,a vintage 1970s hk 402 which also worked very well,always had tons of volume with each one. My vons are 87db I also have a cary rocket 88 tube power amp 20 watts class a or 40 ab never a problem.The anthem is not the problem it has tons of power,it is the transcendent,I have readed alot were these pres have to much gain in alot of systems not so in mine.Would like to know if there is an ajustment I can make in the preamp itself.The preamp really does sounds great, best I have had in my system yet,any help to this problem would be greatly appreciated. Thanks Maxwell
I don't think that there is anything you will be able to do other than to get a different preamp. I have experimented vintage equipment myself. Amps are one thing but I wouldn't use a vintage preamp. It's just too important a component and, I feel, that the newer ones are much better than vintage.
Maxwell: ...I have very little gain. I will have the volume turned up to seven and it is just at a normal level."

'7' compared to what? Most level controls start at zero at 7-o'clock, so you must mean something else.

If you're able to operate your level control in the highest quarter of rotation, you system's gain structure is just about right. Most music systems have too much gain and must be operated with the preamp in its 'cut' range instead of its 'gain' range. Lots of us seem to think that something bad is happening if a preamp is operated near or at its highest-gain range; it's NOT bad, it's good.

So...what does '7' mean? And can your system play as loudly as you want it to?
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Agree with Jeffreybehr. I much prefer the volume control past the 12 o'clock position and closer to 2 or 3 o'clock for normal listening. I assume 7 is at the top end of the range. What happens when you move the volume control higher, say all the way to full open?
Jeff,sorry I mean on a scale of 1 to 10 seven is like 1:30 I can not play as loud as I would like it to.George made the suggestion of trying a tube with more gain,sounds like a good idear,but I will call transcendent and see what they think.And to answer clio09 I have not tried it all the way to full open yet.I will let you all know what happens ,thank you for all your help maxwell
Don't do anything. Don't change tubes and there is not even a need to call the manufacturer. As others have pointed out your system is operating exactly as it should. In case I haven't been clear -- you don't have a gain problem.
Why does it matter if the volume knob is set at 7? 7 is completely arbitrary.

Assuming your source has a fairly normal output voltage, your preamp should have plenty of gain to drive your amplifier to full power.

The real question is, at maximum volume, is your amp + preamp combination able to drive the speakers to the loudest you ever care to listen to?

If so, there is no problem.
Yep, Onhwy61 and others are right on.

I think you might look at in a different manner though. A pre-amplifier's amplifying section comes after the volume control an is always seen by the amp at its full output (gain). The volume control is an attenuator between your source and the pre-amp's amplifier section. When fully rotated the VC is allowing the gain of the source to pass to the pre-amp at full value. When the VC is rotated counter-wise it reduces the gain from the source, it does not reduce the gain from the pre-amp itself, nothing does - it is a constant.

Make sense to you? Take our word for it, you're in hog heaven.
> And to answer clio09 I have not tried it all the
> way to full open yet.

So ... you can turn it to 8, 9, 10, 11, etc and presumably play louder and you haven't? If you want it to play louder, turn it up. There's nothing special about 7. And there's nothing harmful about turning it to 8.

The Grounded Grid just has a different gain structure than you've been previously familiar. If you can play as loudly as you can possibly stand, then you're golden.

Personally, I'd love to have as much range of volume control as you seem to have. What you have now is fine grained control over your volume -- that's awesome.
A pre-amplifier's amplifying section comes after the volume control and is always seen by the amp at its full output (gain).

Very often the case, but I can think of two manufacturers that implement the volume control after the gain section of the preamp and at the output.
Clio, I'm sure you are right, but I don't understand the value of such an arrangement unless you are using an attenuator with fixed impedance values so the impedance value seen by the amp is constant. Is that not why most amplifying sections come after the attenuator?

I guess in hog heaven an attenuator with fixed impedance values coming after the preamp' amplifying section could be optimum as it would not only control volume it would lower the pre-amps noise level as seen by the amp something of much value and could also make interface with various amp input sensitivity levels more efficiently. No more problem with high gain pre-amps and high sensitivity amp inputs, a common real problem. Keeps Rothwell busy I think.

Do you know why they actually use such a configuration? Do you know why they don't?
My amp(Decware Torii 3) and preamp (Artemis LA-1) both have a volume control. Do I want the pre up as much as possible and then phase in the amp?
"jeffreybehr: "And can your system play as loudly as you want it to?"

Maxwell, does your system play as loudly as you want it to?
Onhwy61, Yes that makes sense,I would like to thank everyone who has taken the time to give me there advise,everything sounds great and is working as it should,just not use to having gain at the end of the vc.Thank you Maxwell
Hmmm, since the Grounded Grid is a DIY preamp kit my recommendation is to contact the seller/designer of these kits Bruce Rozenblit and get his opinion on this. With the gain structure that Phil laid out, I'd also say that something sounds a bit fishy.
I've had a Grounded Grid before, with 101 db efficient speakers. The volume knob was at about 9 o'clock. With 87 db efficient speakers, is 1 o'clock reasonable? Seems like it might be ...
> My amp(Decware Torii 3) and preamp
> (Artemis LA-1) both have a volume
> control. Do I want the pre up as much
> as possible and then phase in the amp?

I think the correct answer is: whichever way sounds better. But if I were in your situation I would try some different approaches:

1. Try it with no preamp at all. Source direct to the

2. Decware with volume control at full open.

3. Decware set to a level such that if the volume control of the preamp were full open that it would be the loudest level you would ever consider listening at. This would give you full range of control with the preamp, assuming you actually want to control volume from the preamp.
I think the best gain control on an amp is no gain control. It is convienient perhaps when your pre-amp is noisy or has too much gain to give you full use of the VC on your pre-amp, but you don't really need the minor degredation its use can create. Turn it to maximum and use the pre-amp VC. Now if you have a noisy gain stage in the pre-amp it can help reduce the noise - for me no noise is a bit better than minor degredation by the addition of a second attenuator.
Wilsynet thanks. I agree with the what sounds best to me opinion, but always like to get as much input from others who have had similar experience to see if something can be done that makes more sense from a technical stand point.

Tried 1. and like the pre in the mix.

Tried 2. and with both channels full open on the pre(I have separate channel gain in addition to volume gain on pre) I can not go more than 1 or 2 steps on the volume(-54 to -64)of the pre. Would like a bit more control.

Of your suggestions 3 works best.

I guess the other question is with two quality components does it really matter which one you control the volume with or if indeed it sounds fine using both volumes to some extant is there any technical reason why that would be the least desirable?

Thanks again for your input.
Wilsynet,yes you are correct,it is great having so much control over the gain,just took a day to get use to it. Thanks Maxwell
Newbee, I can't speak to others designs but in ours we are using transformers at the input to significantly increase voltage gain as the signal is fed from the source component (ex. 2V source output becomes 16V). The 10K potentiometer is placed after the transformers to attenuate the gain to achieve desired listening levels. The output impedance remains fixed and due to this the frequency response does not change as volume is attenuated. Note that the design uses all passive parts. No active gain stage.
One more question,since the grounded grid is without a mute switch should I turn it off when not in use,or just leave on all the time.? Thanks Maxwell
Since it is tubed, I'd turn it off for the sake of tube life, or unexpected tube "surprises" when you are not around...