Monoprice Cavalli Liquid Spark technical measurements
post-14536056
Thread Starter
Post #1 of 10

atomicbob

500+ Head-Fier
Joined
May 27, 2012
Messages
985
Reaction score
1,025
Joined
May 27, 2012
Posts
985
Likes
1,025
Monoprice Cavalli Liquid Spark technical measurements

If you are unfamiliar with audio measurements please use a search engine with the query:
"audio measurements" or "audio measurement handbook"
Look for publications by Richard C. Cabot and also by Bob Metzler, both from Audio Precision. There are other useful publications as well. These will provide basic knowledge.
Interpretation of the following measurements is beyond the scope of this post.

The data presented were collected as follows:

1. PrismSound dScope III, picoscope 5243B, Keysight 34461A DMM
2. 300 and 30 ohm loads used for measurements
3. Unbalanced cables Worlds Best Cable Gotham GAC-2 RCA
4. Vaunix Lab Brick USB hub for measurement equipment
5. Audioquest Forest and Schiit Pyst USB cables used for measurement equipment
6. Amplifier gain adjusted to 0 dB gain @ 0.775 Vrms 0 dBu
7. Spark gain switch set to high position
8. Spark gain knob at approximately 1:00 to achieve 0 dB gain
9. 36V SMPS for power except where noted
10. 14 and 16 AWG sheilded power cables used

Reference levels :
+9 dBu 300R 16.00 mW - 110 dBSPL @ 98dB/mW
0 dBu 300R 2.00 mW - 101 dBSPL @ 98dB/mW
-10 dBu 300R 0.20 mW - 91 dBSPL @ 98dB/mW
-20 dBu 300R 0.02 mW - 81 dBSPL @ 98dB/mW

+9 dBu 30R 160.00 mW - 110 dBSPL @ 89dB/mW
0 dBu 30R 20.00 mW - 102 dBSPL @ 89dB/mW
-10 dBu 30R 2.00 mW - 92 dBSPL @ 89dB/mW
-20 dBu 30R 0.20 mW - 82 dBSPL @ 89dB/mW

Reference data on two headphones:
HD 650 impedance 300R, sensitivity 98 dB/mW
HE-500 impedance 38R, sensitivity 89 dB/mW

Highlights
Square wave response is very near that of the Liquid Crimson.
Bandwidth is extraordinary for an amp at this price: DC to > 1.5 MHz

My personal preferences include listening typically at an average of 75 dB SPL. Assuming a typical Peak to Average ratio of 10 dB puts peaks at 85 dB SPL. This suggests the measurements at -20 dBu represent my experience with HD6x0 and HD800 headphones. Auditory experiences for someone listening 10 dB SPL average higher may diverge from my own experiences.

editorial - I believe there is a tendency to focus excessively on numbers such as THD attempting to reduce a complex topic to a single number representing a sort of goodness rating. Graphs can present far more data conveying a better understanding of the measurement over a range of frequency, levels, etc. Please don't read too much into the numbers presented.

Picture of the Audio Lab setup for Liquid Spark measurements
20181005 spark dScope 5243b - t2 - small.jpg


300 ohm load part 1 of 3

Liquid Spark THD+N THD nth harmonic distortion (A04) FFT 0dBu 300R load
20181005 spark A04 THD+N  THD  nth-HD FFT 300R 4XF - SMPS 1.png


Liquid Spark THD THD+N vs Freq 0dBu 300R
20181005 spark THD THD+N vs Freq 300R 4XF.png


Liquid Spark 1 KHz spectrum Left and Right 0dBu 300R load
20181005 spark 1 KHz THD+N THD FFT 0dBu 300R 4XF.png


Liquid Spark 50 Hz + 7000 Hz spectrum Left and Right 0dBu 300R load
20181005 spark 50+7000Hz 0dBu 300R 4XF.png


Liquid Spark 600 Hz + 1700 Hz spectrum Left and Right 0dBu 300R load
20181005 spark 600+1700Hz 0dBu 300R 4XF.png


Liquid Spark IMD spectrum Left and Right -16dBu 300R load
20181005 spark 19+20KHz -16dBu 300R 4XF.png


Liquid Spark residual noise spectrum Left and Right A=0dB 300R load
20181005 spark residual noise A=0dB 300R 4XF - SMPS 1.png
 
Last edited:
post-14536057
Post #2 of 10

atomicbob

500+ Head-Fier
Joined
May 27, 2012
Messages
985
Reaction score
1,025
Joined
May 27, 2012
Posts
985
Likes
1,025
300 ohm load part 2 of 3

Liquid Spark square wave 20 Hz 2 Vpp 10 mS / div 300R load 100 KHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10mS div 100KHz filter 300R.png


Liquid Spark square wave 20 Hz 2 Vpp 10 mS / div 300R load 10 MHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10mS div 5MHz filter 300R.png


Liquid Spark square wave 20 Hz 2 Vpp 10 uS / div 300R load 100 KHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10uS div 100KHz filter 300R.png


Liquid Spark square wave 20 Hz 2 Vpp 10 uS / div 300R load 10 MHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10uS div 5MHz filter 300R.png


Liquid Spark square wave 20 Hz 2 Vpp 50 nS / div 300R load 10 MHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 50nS div 10MHz filter 300R -BW calc.png


Bandwidth estimation: BW (MHz) = 0.35 / RT (mS)
Where RT = 10 to 90% Rise Time
0.35 / 0.186 mS = 1.88 MHz

Liquid Spark amplitude - phase - gain (A01) 300R load
20181005 spark A01 amplitude - phase - gain 300R.png


Liquid Spark signal to noise (A07) 300R load
20181005 spark A07 SNR 300R.png


Liquid Spark THD+N THD nth harmonic distortion (A04) 300R load
20181005 spark A04 THD+N  THD  nth-HD 300R.png


Liquid Spark Crosstalk (A08 A09) 300R load
20181005 spark A08 A09 Crosstalk 300R.png
 
Last edited:
post-14536058
Post #3 of 10

atomicbob

500+ Head-Fier
Joined
May 27, 2012
Messages
985
Reaction score
1,025
Joined
May 27, 2012
Posts
985
Likes
1,025
300 ohm load part 3 of 3

Liquid Spark Frequency Response and Interchannel Phase pg 1/2 300R load
G2_L1T2_1_A.png


Liquid Spark Frequency Response and Interchannel Phase pg 2/2 300R load
G2_L1T2_1_B.png


Liquid Spark Gain vs Amplitude Left 300R load
G2_L1T3_1_A.png


Liquid Spark Gain vs Amplitude Right 300R load
G2_L1T3_1_B.png


Liquid Spark THD+N vs Frequency Left 300R load
G2_L1T5_1_A.png


Liquid Spark THD+N vs Frequency Right 300R load
G2_L1T5_1_B.png


Liquid Spark THD+N vs Amplitude Left 300R load
G2_L1T6_1_A.png


Liquid Spark THD+N vs Amplitude Right 300R load
G2_L1T6_1_B.png


Liquid Spark Crosstalk Left to Right vs Frequency 300R load
G1_L1T10_1.png


Liquid Spark Crosstalk Right to Left vs Frequency 300R load
G0_L1T11_1.png
 
Last edited:
post-14536060
Post #4 of 10

atomicbob

500+ Head-Fier
Joined
May 27, 2012
Messages
985
Reaction score
1,025
Joined
May 27, 2012
Posts
985
Likes
1,025
30 ohm load part 1 of 3

Liquid Spark THD+N THD nth harmonic distortion (A04) FFT 0dBu 30R load
20181005 spark A04 THD+N  THD  nth-HD FFT 30R 4XF.png


Liquid Spark THD THD+N vs Freq 0dBu 30R
20181005 spark THD THD+N vs Freq 30R 4XF.png


Liquid Spark 1 KHz spectrum Left and Right 0dBu 30R load
20181005 spark 1 KHz THD+N THD FFT 0dBu 30R 4XF.png


Liquid Spark 50 Hz + 7000 Hz spectrum Left and Right 0dBu 30R load
20181005 spark 50+7000Hz 0dBu 30R 4XF.png


Liquid Spark 600 Hz + 1700 Hz spectrum Left and Right 0dBu 30R load
20181005 spark 600+1700Hz 0dBu 30R 4XF.png


Liquid Spark IMD spectrum Left and Right -16dBu 30R load
20181005 spark 19+20KHz -16dBu 30R 4XF.png


Liquid Spark residual noise spectrum Left and Right A=0dB 30R load
20181005 spark residual noise A=0dB 30R 4XF.png
 
Last edited:
post-14536061
Post #5 of 10

atomicbob

500+ Head-Fier
Joined
May 27, 2012
Messages
985
Reaction score
1,025
Joined
May 27, 2012
Posts
985
Likes
1,025
30 ohm load part 2 of 3

Liquid Spark square wave 20 Hz 2 Vpp 10 mS / div 30R load 100 KHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10mS div 100KHz filter 30R.png


Liquid Spark square wave 20 Hz 2 Vpp 10 mS / div 30R load 10 MHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10mS div 5MHz filter 30R.png


Liquid Spark square wave 20 Hz 2 Vpp 10 uS / div 30R load 100 KHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10uS div 100KHz filter 30R.png


Liquid Spark square wave 20 Hz 2 Vpp 10 uS / div 30R load 10 MHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 10uS div 5MHz filter 30R.png


Liquid Spark square wave 20 Hz 2 Vpp 50 nS / div 30R load 10 MHz BW
20181005 SigGen spark 20 Hz square 2000mVpp 50nS div 20MHz filter 30R - BW calc.png


Bandwidth estimation: BW (MHz) = 0.35 / RT (mS)
Where RT = 10 to 90% Rise Time
0.35 / 0.220 mS = 1.59 MHz


Liquid Spark amplitude - phase - gain (A01) 30R load
20181005 spark A01 amplitude - phase - gain 30R.png


Liquid Spark signal to noise (A07) 30R load
20181005 spark A07 SNR 30R.png


Liquid Spark THD+N THD nth harmonic distortion (A04) 30R load
20181005 spark A04 THD+N  THD  nth-HD 30R.png


Liquid Spark Crosstalk (A08 A09) 30R load
20181005 spark A08 A09 Crosstalk 30R.png
 
Last edited:
post-14536062
Post #6 of 10

atomicbob

500+ Head-Fier
Joined
May 27, 2012
Messages
985
Reaction score
1,025
Joined
May 27, 2012
Posts
985
Likes
1,025
30 ohm load part 3 of 3

Liquid Spark Frequency Response and Interchannel Phase pg 1/2 30R load
G2_L1T2_1_A.png


Liquid Spark Frequency Response and Interchannel Phase pg 2/2 30R load
G2_L1T2_1_B.png


Liquid Spark Gain vs Amplitude Left 30R load
G2_L1T3_1_A.png


Liquid Spark Gain vs Amplitude Right 30R load
G2_L1T3_1_B.png


Liquid Spark THD+N vs Frequency Left 30R load
G2_L1T5_1_A.png


Liquid Spark THD+N vs Frequency Right 30R load
G2_L1T5_1_B.png


Liquid Spark THD+N vs Amplitude Left 30R load
G2_L1T6_1_A.png


Liquid Spark THD+N vs Amplitude Right 30R load
G2_L1T6_1_B.png


Liquid Spark Crosstalk Left to Right vs Frequency 30R load
G1_L1T10_1.png


Liquid Spark Crosstalk Right to Left vs Frequency 30R load
G0_L1T11_1.png
 
Last edited:
post-14536063
Post #7 of 10

atomicbob

500+ Head-Fier
Joined
May 27, 2012
Messages
985
Reaction score
1,025
Joined
May 27, 2012
Posts
985
Likes
1,025
300 ohm load power supply comparison

Liquid Spark residual noise spectrum Left and Right A=0dB 300R load - SMPS supplied
20181005 spark residual noise A=0dB 300R 4XF - SMPS 1.png


Liquid Spark residual noise spectrum Left and Right A=0dB 300R load - SMPS + Noise Nuke
20181005 spark residual noise A=0dB 300R 4XF - noise nuke.png


Liquid Spark residual noise spectrum Left and Right A=0dB 300R load - BK1623A LPS
20181005 spark residual noise A=0dB 300R 4XF - BK1623A LPS.png


Residual noise on the Liquid Spark definitely benefits from a quiet LPS. Noise Nuke moderately improved residual noise.


Liquid Spark THD+N THD nth harmonic distortion (A04) FFT 0dBu 300R load - SMPS supplied
20181005 spark A04 THD+N  THD  nth-HD FFT 300R 4XF - SMPS 1.png


Liquid Spark THD+N THD nth harmonic distortion (A04) FFT 0dBu 300R load - SMPS + Noise Nuke
20181005 spark A04 THD+N  THD  nth-HD FFT 300R 4XF - noise nuke.png


Liquid Spark THD+N THD nth harmonic distortion (A04) FFT 0dBu 300R load - BK1623A LPS
20181005 spark A04 THD+N  THD  nth-HD FFT 300R 4XF - BK1623A LPS.png


30 Hz residual is reduced by the Noise Nuke; completely gone with an LPS. Distortion differences measured are insignificant between the three.
 
Last edited:
post-14593338
Post #9 of 10

legion1capone

100+ Head-Fier
Joined
Oct 12, 2013
Messages
116
Reaction score
60
Location
Washington State
Joined
Oct 12, 2013
Location
Washington State
Posts
116
Likes
60
How do these measurements compare to the JDS EL Amp?
 
     Share This Post       
post-14748185
Post #10 of 10

Zachik

Headphoneus Supremus
Joined
Jan 15, 2015
Messages
3,477
Reaction score
2,778
Joined
Jan 15, 2015
Posts
3,477
Likes
2,778
     Share This Post       

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top