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Upgrade Preamp


AnalOg

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I've been eyeballing preamps, even though my Foreplay does a great job for the price. I have a couple of issues now that I have the La Scala's in place that are leading me to go shopping. The biggest issue is, I can't get the vloume low enough for late night listening. I know I can change the shunt resistors, I've been down this road before with minimal results.

Anyways, I really like the what the Rogue ninety nine Magnum has to offer. Price wise & tube topology. Does anyone have any experience and/or comments on this Pre.

Tom

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It seems nice enough, but 23db of gain in the line stage is not going to help your cause here.

The Anthem phono stage you have is actually a really nice unit, so you really don't need something with a phono stage. I would venture a guess that the stand alone Anthem unit is much better than something integrated into a full feature preamp.

What you really need is something like my Cary, where you can adjust the gain settings.

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"but 23db of gain in the line stage is not going to help your cause here."

Dean,

I should have been more specific. The preamp I'm considering does'nt have the phono stage. As I really like what the Anthem does.

I'm not sure I follow your comments on the gain issue, can you clarify?

Tom

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You originally said -- "The biggest issue is, I can't get the volume low enough for late night listening."

That is a gain issue. You barely turn it up -- and it's louder than you want it to be. A preamp with 23db of gain will be as bad or worse than what you have now. A preamp with less gain will send less to the Dynaco at any given point on the volume control. For example, instead of being blown out of the room at the 10 o'clock position -- you could go to 1 o'clock. Inversely, just a tick on the dial gives you good low level listening, instead of having your wife throw things at you.1.gif

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Dean,

Again, I should have been more specific. The reason why I can't turn the volume down low enough with the Foreplay, it has stepped attenuators, Ive already changed out all the resistors to a -20 to -50 config. I don't want to change them all out again to a different config.

tom

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This might sound kinda stupid to those of you who are more technically (electronically speaking) astute than I, but can't you just build a simple stereo "L" pad or "T" pad to accomplish this? Something simliar to, if not exactly the same as what's used in the Klipsch '2ph3' center channel phantom circut?

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The gain of the Foreplay can be dealt with, and you DON'T have to change all the resistors in you volume controls. Use series resistance on the input. A fixed resistor of the same value of your volume controls will bring the volume down by about 6 dBs. For example, if you have 100K controls, install a 100K ohm resistor between the selector switch an each of the input lugs on the pots. Just tack in different values of R until you achieve what you are looking for. DON'T use series resistance on the output after the coupling capacitors, though. That will do nothing but jack up the output impedance of your preamp, making it difficult to drive lengths of interconnect, reduce the HF response, and other not good sorts of things.

The preamp you are considering is not going to help the problem unless it has gain controls.

If your sources are within a few feet of your amplifiers, likely all you really need is a passive preamplifier. The output of your CD player is enough to send your amplifiers into the clipping range, already.

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I already have a 90k shunt resistors in series. I'm aware of the adding of resistence in series will attenuate the volume more so. I did this before with the -30 to 0 config. I added almost 500k to the shunt, didn't care for the results. I took the attenuators apart, changed out all the resistors to a -50 to -20 config. with a 90k shunt. Better results with the RF3's in place. Now I'm back to square on with the La Scala's, not in the mood to start messing with it again, maybe in the winter months.

Maybe this is just an excuse to try something different with a REMOTE.9.gif

Does everyone on the forum experience the same problem with low level listening or does everyone have gain controls on there preamps?

Tom1.gif

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O.k. I did it. got me the Rogue Magnum Ninety Nine. I need to see if upgrading the preamp will give the balance that I'm looking for. I'm also hoping to tighten the imaging up a bit.

For sure, I need to treat the room, the heating ducts above to the left are big problem. I'm going to address the room issues after I implement the Rogue into the system.

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