suitable preamp DIY

[Nate805]

What is a good (simple & clean) pre-amp kit or classic schematic (like the gainclone) for a pre-amp suitable for use with my pa-150 (3 lm3886s per channel) amplifier. I'm interested in both tube and silicon options. Any favorites for this combo? Pros Cons? thanks much in advance

[merlin2069er]

You should consider a lightspeed attenuator, or put together a stepped attenuator with some rca jacks.

[ratza]

What are your expectations regarding preamp's performance (distortion, voltage in, voltage out, input and output impedace etc).

[Nate805]

I'm not terribly knowledgable about analog, all i know is I want a good sounding (low noise / THD) chip or tube preamp with a high input impedance that would work good with my gainclone / iPod or CD player combo.

[Nate805]

6SN7 SRPP Tube Pre Amplifier DIY Kit (Stereo ) Basic - eBay (item 320546692713 end time Jul-10-10 22:25:53 PDT)

what about this?

[tangmonster]

what do you want to use the preamp for?
what are your sources you want to connect?

that preamp has no input selector / riaa function. Why add more stuff if you in the audio route if you are not gaining anything.

[Nate805]

i want to use the preamp with my gainclone, (parallel 150w with lm3886s) to achieve more gain, because it just isn't half as loud as it should be when driven by my ipod or CD player. i'm not sure if i'll need to implement input selection, and for now, i have no record player, so no issue there.

[ashok]

What's the input sensitivity of your power amp ? I'm guessing the gain of the amp is greater than 24 dB.
A typically CD player output is about 2 V rms or at least 1.5 volts rms.
Your iPod is about 0.8 volts ( into 24 ohms) I believe. The CD player should clip the amp but the iPod might not.

You need just x3 gain max. Most preamp tubes except types like the 12B4A will give you far more gain than you require ( without NFB ). Opamps and discrete circuits can give you less gain more easily. However they all have their sonic signature . Some discrete preamps might sound great compared to opamps. But application can make a whole lot of difference.

I'd suggest using a good opamp implementation. Simple and it will sound nice.
With an iPod signal I don't think the preamp is 'that' critical. Maybe even a NE5534 would do ! Yes that one is looked down upon by many but still used by many respected designers. You could always check it out as it costs almost nothing.

[Nate805]

thanks for the good info, how would i go about measuring the output voltage of my cd player?

Also I'm not an EE, i would rather follow a schematic or get a preamp kit than attempt to design my own; any suggestions?

[Redshift187]

What speakers are you using? If they are 8 ohm, you aren't getting nearly as much power from the PA150 as you might think.