Preamp after phono stage?

[OsoAlfa]

Is there value in placing a preamp between the phono-preamp and my integrated amplifier? I’d like to boost the final volume level without increasing the gain on my phono stage. I use my Integra Surround Sound amplifier in “Stereo” mode which sends signal to my two main 4ohm speakers AND my subwoofer. It’s a fantastic feature but I’d like to increase the line level I think. The Integra gives me 135 W per channel, and it drives the speakers well. I can increase the gain on the phono preamp but it introduces more noise than I like. I can increase the relative volume output on the Integra but that just makes it louder and I feel like it thins out the sound stage a bit by doing that. I’m looking for more weight in the sound stage, I want it to be heavier at lower volume levels. I need to bring the system up to about 65 volume units (to fill the room) and it tops out at 85. I’d like for it to be louder at about 50… It's plenty loud at 50 for Dolby Digital, etc. from other inputs. I thought about adding a power amp for the Paradigm speakers, but then the levels won’t match for the subwoofer. That’s why I thought I’d lift the signal earlier in the configuration chain.

Any suggestions would be helpful.

Here is what I am using now:

Dual 1245 turntable (original)
Denon DL-103 MC (new)
Pro-Ject Tube Box S
Integra DTR 50.2
Paradigm 9se mkII
Infinity IL 10 powered sub

 

[JoeESP9]

No! For most systems the phono input has lower overall gain. Do like the rest of us do. Increase the volume when playing vinyl.

 

[Audiovet]

OsoAlfa,

i am a bit confused here. You want to 'boost the final volume level'. That means increasing the gain somewhere, whether by an extra stage anywhere or turning up the volume level. Any of this will increase the background noise, which usually starts at the input stage - whether phono or whatever signal source there is. The signal/noise ratio is not changed by the volume control; increasing the final volume will necessarily increase the noise. Wanting it 'heavier at lower volume levels' also sounds like you may want a 'loudness' feature somewhere. ('Loudness' controls turn down the low frequencies less than the rest to compensate for hearing's characteristics.)

If it is 'plenty loud' for other inputs, it simply means that you do want somewhat more gain for phono to match, or turn up the volume as JoeESP9 suggested. Perhaps I do not understand what you are asking.

 

[OsoAlfa]

Ok, thank you. I have the phono pre-amp plugged into the CD port of the amplifier. If I plug it into the phono port, it's totally distorted. Maybe I'll play more with the gain settings on the phono preamp to see if I can find a better middle ground.

 

[4-2-7]

Ok, thank you. I have the phono pre-amp plugged into the CD port of the amplifier. If I plug it into the phono port, it's totally distorted. Maybe I'll play more with the gain settings on the phono preamp to see if I can find a better middle ground.

You do not plug a stand alone phono stage with RIAA equalisation into another another phono stage built into a preamp, reciever or integrate with RIAA eqing

There is ways to boost the gain prior to a RIAA phono stage. It's called a SUT or Phono Head Amp, they can have adjustable loading and gain setting but no RIAA eqing and they will plug into the phono input of the preamp.

I take it your preamp/reciever does not have MC inputs so you lack quiet a bit of volume when playing records.

 

[sheltie dave]

Oso, the independent phono preamp changes(increases) the output of the TT signal to a line level. You will be good using the cd/line/tape input on the integrated amp.

DO NOT use the phono input, as you have already had the TT signal increased by about 25/30 dB. That is why you are gettiung tremendous distortion when you use the phono input from the independent phono preamp.

 

[4-2-7]

• DL-103

• Frequency response (Hz): 20-45,000

• Output@1khz, 50mm/sec: .3mV

• Output impedance: 40 ohms

• Load impedance: 100ohms

• Channel seperation at 1kHz: over 25db

• Channel sensitivity: 1dB or less

• Tracking tip: 16.5 micron special round solid diamond

• Copliance: 5x10-6cm/dyne (100Hz)

• Tracking force- 2.3~2.7g

• Cantilever: aluminum, conical

• Mass: 8.5g

Tube Box S

• Audiophile-grade ECC83 (12AX7)

• Dual mono configuration

• Audiophile-grade polypropylene WIMA capacitors

• Precise RIAA equalisation

• Switchable input impedance/capacitance

• 3 adjustable gain levels

• Subsonic filter

• DC power supply (< 1 watt standby power)

• Available in silver and black


Set the box to the 100ohm impedance

then try the highest gain setting for the stage.