wiim pro with vintage monster receiver

[andras]

Hello Champs,
Fairly new still learning and I have a question and wonder if you came across the same experience.
The system:
- wiim pro
- sansui 9090db (124Wpc nominal, 8Ohm)
- yamaha NS1000x (8Ohm 200W) and
- diatone ds-77HRX (6 Ohm 280W)
so the one may think plenty of headroom…
When I have the wiim pro on 100% volume (2Vmrs) and I turn the sansui volume above 20%, my subs from the yamaha - which can take a lot abuse btw - are about to fly away. Needless to say I did not stretch furter. Is it possible that the analog output of the wiim with combination of a 125W vintage amp can kill a speaker at 30% amp volume? I know these are old stuff but I wonder what you guys think. Many Thanks

 

[Valentino]

The WiiM Pro has four selectable line output levels, and all are 100%.
2V is obviously too much for a comfortable use of your volume control. Try 1V. If that's still too much try 800 mV. And if that is too much try 500 mV. Good luck and report back please.

 

[harkpabst]

Hello Champs,
...

By the way, that vintage equalizer with the funny v shaped settings per channel is not connected anywhere, is it? It's just there for good looks, right?

 

[cooky560]

I use a lot of vintage stuff, I find setting the WiiM to 0.5v works great with it, vintage gear used much lower voltage for input than today.

 

[Fitzliputzli]

Should one try to keep the line output as high or as low as possible?

 

[harkpabst]

Should one try to keep the line output as high or as low as possible?

Neither nor. It should match the input sensitivity of the next device in the chain.

Since the advent of CD palyers, 2 Vrms have pretty much become the norm for unbalanced RCA inputs. Older devices often have an input sensitivity of 775 mVrms, 500 mVrms or less. Some inputs dedicated to FM tuners might have an input sensitivity as low high as 150 mVrms.

For reference: The input sensitivity is the voltage required on the input to get the maximum possible voltage (without clipping) at the output.

Edit:
With input sensitivity, lower numbers mean higher sensitivity, of course.

 

[Yoku-San]

Setting output voltage to 0.5v will also avoid potential damage by children. Or you set output to 2V and then limit maximum volume to the value which you can hardly tolerate.

 

[cooky560]

Every amp I have since before the 90s has an input voltage of 0.1v, I always find them messy when using CD players, but the WiiM's 0.5 setting really helps.

It doesn't matter in that using a higher voltage won't kill your amps, however you'll find the volume control limiting if the input voltage is massively higher than the input sensitivity on the amplifier.

 

[Yoku-San]

with my Wiim Ultra, the volume control stays from 0-100 if I set maximum level to 75. There are still 1/100 increments from 0-75 then.

 

[cooky560]

with my Wiim Ultra, the volume control stays from 0-100 if I set maximum level to 75. There are still 1/100 increments from 0-75 then.

Yes, the maximum volume adjusts what 100% on the volume dial means, rather than limiting you to part of the volume dial. Think of it like the old skool "muting" switches, where you still had the full dial, but it gave you less volume.

 

[andras]

By the way, that vintage equalizer with the funny v shaped settings per channel is not connected anywhere, is it? It's just there for good looks, right?

good catch, sorry I missed the EQ witht he funny V that is a pioneer SG-9

 

[andras]

good catch, sorry I missed the EQ witht he funny V that is a pioneer SG-9

and it is part of the loop

 

[Erebus]

With input sensitivity, lower numbers mean higher sensitivity, of course.

This is very useful info, thank you. What WiiM Pro Plus line out setting would you recommend for a Fosi BT20A amp with 280mV input sensitivity?

 

[andras]

Many thanks champs, I got what I came for. Matching the input sensitivity was one of many holes in my knowledge

 

[andras]

The WiiM Pro has four selectable line output levels, and all are 100%.
2V is obviously too much for a comfortable use of your volume control. Try 1V. If that's still too much try 800 mV. And if that is too much try 500 mV. Good luck and report back please.

some research: sansui 9090db line input sensitivity is 150mV. Now with the wiim on 200mV can get the amp volume up to 80% and no distortion. Problem solved

 

[harkpabst]

Every amp I have since before the 90s has an input voltage of 0.1v, I always find them messy when using CD players, but the WiiM's 0.5 setting really helps.

Anything below 150 mV would have been highly unusual even in the 1980s. And that's for integrated amplifiers. Power amps would usually have a lower input sensitivity, since matching pre-amps had a higher output volume.

some research: sansui 9090db line input sensitivity is 150mV. Now with the wiim on 200mV can get the amp volume up to 80% and no distortion. Problem solved

Great. In the first place, the reason for matching output voltage and input sensitivity is to minimise hum and noise. A convenient range of the volume knob and protection from potential mishaps are of lesser importance, but not to be ignored, of course. With typical (older) volume pots the channel imbalance at low settings can always be a bit problematic.

 

[Valentino]

Anecdotal I remember padding down the CD input on a beautiful Tandberg 3000 series preamp a loong time ago to make the volume control useful also when playing silver disks. Full whack at 10 o'clock was not ideal.

 

[Yoku-San]

This is very useful info, thank you. What WiiM Pro Plus line out setting would you recommend for a Fosi BT20A amp with 280mV input sensitivity?

I would set the WiiM Pro Plus to 2V output, set the volume wheel of the BT20A amp to your maximum tolerable loudness level and then use digital volume control of the Wiim.

 

[LesE]

Here is the approach I took with my vintage receiver (Pioneer SX-1250). I separated the power amplifier from the pre-amplifier (jumper removal) and connected my WiiM Ultra line out (set to variable output with volume at 0) to the power amp in. Then I connected from the last monitor point in the receiver (Adapter Out on the SX-1250) to the WiiM line input. This effectively eliminates the active part of the Pioneer pre-amp along with all of the controls such as volume, balance, muting and filters while still allowing for access to the tuner, turntables, CD player and tape decks. Source selection on the receiver functions normally. The only thing I'm losing with this configuration is noise .

I usually don't use tone controls or loudness but that functionality is available in the Home app if desired. An additional bonus of the variable output on WiiM is the availability of bass management if you have an Ultra and are using a subwoofer (which I am). Plus, there is also the added convenience of being able to control the volume using the remote.

I just want to reiterate that you should change the WiiM to variable output with the volume set to 0 before connecting to the receiver's power amp to prevent any unfortunate accidents.

 

[harkpabst]

I would set the WiiM Pro Plus to 2V output, set the volume wheel of the BT20A amp to your maximum tolerable loudness level and then use digital volume control of the Wiim.

Honestly, I don't see the advantage of this approach. Personally, I would probably use the digital volume control of the WiiM Pro Plus, too. But I would rather set the WiiM's output voltage to 200 mVrms, and fully crank up the volume on the BT20A. This will leave a small security margin so the amp will never got into clipping.

@Erebus, only if the output power is too limited (WiiM and BT20A at 100%) I would consider to increase the output voltage to 500 mVrms.