"Boosting" Phono Stage Output?

Instead of dancing around the problem, figure out your specs. What is the actual output of your current cartridge in MV? No guessing, look it up. What is the actual gain level of your receiver's phono preamp? Again, look it up.

I was merely answering the other member...

Finally, are you 100% sure everything is hooked up correctly?

Yes.
 
I was merely answering the other member...



Yes.

According to the KAB calculator, optimum phono preamp gain is 39db. I've found the calculator errs on the low side, you could probably go up to say 42db with no ill effect. You'd have to experiment and try it though. I would definitely not jack up the gain too much higher than that unless you want distortion.
 
Thanks. Sarcasm is like a second language to me, so I'm riiiiiight there with cha.

What I'm actually asking is if there was a way to boost the pre-line signal so I don't have to turn the volume knob up all that much.

You're welcome! Glad I didn't hurt your feelers. As you probably have gathered, in a high-fidelity context, your goal is silly. It is like not wanting to press the gas pedal down any further when driving up a hill. But you seem determined, even stubborn, in your silliness. A step-up transformer with a low windings ratio, say 2:1 or 3:1, might do what you want. Or it might overload your phono stage - hard to predict. Or, you could install a graphic equalizer, and push all the sliders up to the top... :D
 
According to the KAB calculator, optimum phono preamp gain is 39db. I've found the calculator errs on the low side, you could probably go up to say 42db with no ill effect. You'd have to experiment and try it though. I would definitely not jack up the gain too much higher than that unless you want distortion.

I'm running an AT95e with an Onkyo TX-8555; is this a mismatch maybe?
 
You're welcome! Glad I didn't hurt your feelers. As you probably have gathered, in a high-fidelity context, your goal is silly. It is like not wanting to press the gas pedal down any further when driving up a hill. But you seem determined, even stubborn, in your silliness. A step-up transformer with a low windings ratio, say 2:1 or 3:1, might do what you want. Or it might overload your phono stage - hard to predict. Or, you could install a graphic equalizer, and push all the sliders up to the top... :D

As I said...

Sarcasm has been studied as a second language, so I'm right there wit cha! :beerchug:
 
Anyway, thanks everyone (else) for your input and suggestions; it's probably as folks like patient ot said -- since there's no "device" that can be placed in line between the device itself and a phono preamp to boost gain on said preamp, I'll have to either live with raising the volume knob or look into getting a separate phono pre with adjustable gain (which I didn't really want to get into). I could always play with turning the gain of my preamp level control inside the receiver to maximum (I'm three notches away from that now, and the turntable input still isn't all that "hot").

I'll also consider a "hotter" cartridge replacement (in terms of voltage output).
 
since there's no "device" that can be placed in line between the device itself and a phono preamp to boost gain on said preamp

There is, you could build and use an active preamp like the Simple Preamp I designed and adjust the gain to suit, you won't need much, but if you are going to do that you may as well just go with an external phono stage like the DIY CNC, it's sure to sound better than the one in the Onkyo. You could also get someone with the knowledge to open up the Onkyo (and void the warranty) to increase the gain of the Onkyo's phono stage by swapping out some gain resistors, there probably surface mount so not for the faint hearted.
 
There is, you could build and use an active preamp like the Simple Preamp I designed and adjust the gain to suit, you won't need much, but if you are going to do that you may as well just go with an external phono stage like the DIY CNC, it's sure to sound better than the one in the Onkyo. You could also get someone with the knowledge to open up the Onkyo (and void the warranty) to increase the gain of the Onkyo's phono stage by swapping out some gain resistors, there probably surface mount so not for the faint hearted.

Thanks Hypno; doesn't sound like something I'd want to get into but I appreciate the suggestion. I was more interested in a ready-made device that could slip between it and a phono stage to boost its gain, but if this doesn't exist (outside of customized solutions like you mentioned) I will have to work around it.

As an aside, there's really nothing worth "complaining about" with regard to the phono stage in my Onkyo; the sound itself seems balanced and fine -- it's just the output level I was concerned with. I truly like this stereo receiver and have enjoyed using it since the day I got it....good, clean, solid power (on sources other than the aforementioned phono input, such as CD or tuner) and a rock-solid chassis with thick aluminum faceplate that makes the whole unit feel like a good integrated that just happens to have a tuner built in.:thumbsup:
 
I'm running an AT95e with an Onkyo TX-8555; is this a mismatch maybe?

The manual for your receiver doesn't list the default gain on the unit's phono preamp. Contact Onkyo and see if they give you an answer. The gain numbers in my previous post were based on the output of your cart run through the KAB calculator which I also linked.
 
I'd rather have a hotter output lower down on the volume scale.

Be careful with this theory--it can work to crank up the gain on the front end, so that you don't have to run the volume way up on the final amplification stage; however, any distortion/clipping introduced in the source stage is just going to be magnified further down the line as you get to the amplification stage. The old addage of "garbage in = garbage out" holds true--only louder. If you clip the signal up-front (by driving the phono stage volume too high), the damage is done and it will only get worse as you bring up the final volume stage. General rule of thumb is that nothing should be run beyond 70% of maximum gain/output, because all it takes is one cymbal crash or kick drum hit to take you way out of the range of capability of the circuit. Read up (in a pro audio forum preferably) about the concept of "gain structure". Start small and let the final amps do the "heavy lifting". Everything in "the chain" can/will introduce "artifacts", so you want the cleanest possible signal to hit the final amplification stage--if it isn't loud enough, you either need heftier amps or more efficient speakers--or both.
 
Since there is so much gain with the phono preamp already (40db for average mm, 60-65 for MC), its better to increase the volume with the line stage. Most line stage preamps have a very low noise floor, as opposed to phono preamps which can have a bit of a noise floor.

If you are unhappy with your AT's output level, perhaps you could look for a cart that has a bit higher output.

Also keep in mind that higher output cartridges might overload a phono preamp, and that would certainly be counter productive.

I also think that many phono preamps with adjustable output really only work to reduce the output. There is no gain, only attenuation.

'ner
 
Dumb question - have you tried any other cartridges?
One reason I ask, is that sometimes the audio technicas work and sound good, but have low output because the stylus is not completely into the body - we use to see it about once a month when they were new (yeah - a long time ago). Sometimes the gap is only a fingernails width, but will reduce output and give you no other problems. There should be a distinct click or snap when the stylus is properly seated. My 2 cents.
 
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