Abrise
Member
Measurements of 2 amplifiers to try to understand preference.
Between these 2 amps, I prefer the first one.
Magnet 100W 8 Ohms Class AB discrete component 12Kg and 25 years old, locally -Thailand-designed and manufactured. 600€ at the time. Although very old, I am still satisfied with the sound.
Teac AI-501 DA 50W 8 Ohms Class D integrated amplifier based on Abletec ALCO180 modules purchased in 2013 and highly praised in the press at that time. To tell the truth I purchased 700€ this TEAC because of the good reviews and it is integrated with USB and optical inputs but also because it is just small and beautiful.
I always find extremely difficult to put into words my feelings while listening to music. I never had any critics with the old Magnet Amp but I find that sometimes the TEAC is not perfect and that there is some confusion in the medium when playing symphonic type of music. When listening to vocals with simple accompaniment I wouldn’t make any difference.
With a bit of naivety, I am trying to see if it is possible to understand my feelings differences by simply comparing the measurements of these amplifiers.
I believe my measuring tools of at least 20dB better than the devices under test are valid. Ie Rew, smsl su1 or topping E70 to drive the Magnet amp, USB to optical converter to drive TEAC , 4x2 Ohms 200w resistors for dummy load, E1DA Cosmos with smsl isolators for ADC and its bunch of straight and Y cables for stereo or mono.
TEAC AI-501 DA measurements
Optical input is used to drive the TEAC
1000Hz total harmonic distortion and noise at 5W 4Ohms THD+N is -85dB.
It puts it right in the middle of @amirm range of Very good/good amplifiers. As far as SINAD is concerned it is thus not obsolete.
The rest of my measurements are made on 8 Ohms for better flexibility (the four 2 ohms dummy load resistors are used as dividers to adapt to the E1DA cosmos corresponding best voltage inputs in function of power.)
The THD+N under 8 Ohms is as usual a little better: -88dB
The frequency response is no problem although the cut is at 18.5 kHz
I measured the IMD din at 1W 13W and 30W and it gives the same result of around -66 -68dB. Maybe this is a bit high and is the problem.
I have also the THD+N at various frequencies. It is quite OK . The bandwidth is 20-20kHz not like @amirm similar test. The purpose is to measure only what is might be audible.
It shows a max power of around 40W at 8 Ohm
Last but not least is the Multitone test. 16Bit. Not perfect but nothing that bad.
Test of the Magnet amp
1000Hz total harmonic distortion and noise at 5W 8Ohms THD+N is -86dB.
THD+N is similar to TEAC although there is a lot of power supply noise which is not nice but not audible.
Frequency response OK until 18.5kHz
THD+N vs frequency 45kHz bandwidth. Showing max power of 100W and acceptable distortion .
Magnet multitone 5W very similar to TEAC but not better and I would say a little worse. Around 16bits
Combined TEAC and Magnet THD+N vs Level and frequency 1 and 5 kHz.
TEAC : dotted lines
Magnet : plain lines
Besides the power, it is hard to decide which one is better!
Conclusion
If looking only at the measurements one should conclude that the TEAC behaves slightly better. And it is opposite to my preference. I might well be that my preference comes from the difference in power, but I am not totally convinced.
Eventually I have put the TEAC in a secondary setup and purchased a Topping PA7 to replace it.
Here is a comparison. With a 10-year difference we have here a 17dB difference. I am not questioning why I prefer the PA7 !
TEAC : dotted line
PA7 : plain line
Between these 2 amps, I prefer the first one.
Magnet 100W 8 Ohms Class AB discrete component 12Kg and 25 years old, locally -Thailand-designed and manufactured. 600€ at the time. Although very old, I am still satisfied with the sound.
Teac AI-501 DA 50W 8 Ohms Class D integrated amplifier based on Abletec ALCO180 modules purchased in 2013 and highly praised in the press at that time. To tell the truth I purchased 700€ this TEAC because of the good reviews and it is integrated with USB and optical inputs but also because it is just small and beautiful.
I always find extremely difficult to put into words my feelings while listening to music. I never had any critics with the old Magnet Amp but I find that sometimes the TEAC is not perfect and that there is some confusion in the medium when playing symphonic type of music. When listening to vocals with simple accompaniment I wouldn’t make any difference.
With a bit of naivety, I am trying to see if it is possible to understand my feelings differences by simply comparing the measurements of these amplifiers.
I believe my measuring tools of at least 20dB better than the devices under test are valid. Ie Rew, smsl su1 or topping E70 to drive the Magnet amp, USB to optical converter to drive TEAC , 4x2 Ohms 200w resistors for dummy load, E1DA Cosmos with smsl isolators for ADC and its bunch of straight and Y cables for stereo or mono.
TEAC AI-501 DA measurements
Optical input is used to drive the TEAC
1000Hz total harmonic distortion and noise at 5W 4Ohms THD+N is -85dB.
It puts it right in the middle of @amirm range of Very good/good amplifiers. As far as SINAD is concerned it is thus not obsolete.
The rest of my measurements are made on 8 Ohms for better flexibility (the four 2 ohms dummy load resistors are used as dividers to adapt to the E1DA cosmos corresponding best voltage inputs in function of power.)
The THD+N under 8 Ohms is as usual a little better: -88dB
The frequency response is no problem although the cut is at 18.5 kHz
I measured the IMD din at 1W 13W and 30W and it gives the same result of around -66 -68dB. Maybe this is a bit high and is the problem.
I have also the THD+N at various frequencies. It is quite OK . The bandwidth is 20-20kHz not like @amirm similar test. The purpose is to measure only what is might be audible.
It shows a max power of around 40W at 8 Ohm
Last but not least is the Multitone test. 16Bit. Not perfect but nothing that bad.
Test of the Magnet amp
1000Hz total harmonic distortion and noise at 5W 8Ohms THD+N is -86dB.
THD+N is similar to TEAC although there is a lot of power supply noise which is not nice but not audible.
Frequency response OK until 18.5kHz
THD+N vs frequency 45kHz bandwidth. Showing max power of 100W and acceptable distortion .
Magnet multitone 5W very similar to TEAC but not better and I would say a little worse. Around 16bits
Combined TEAC and Magnet THD+N vs Level and frequency 1 and 5 kHz.
TEAC : dotted lines
Magnet : plain lines
Besides the power, it is hard to decide which one is better!
Conclusion
If looking only at the measurements one should conclude that the TEAC behaves slightly better. And it is opposite to my preference. I might well be that my preference comes from the difference in power, but I am not totally convinced.
Eventually I have put the TEAC in a secondary setup and purchased a Topping PA7 to replace it.
Here is a comparison. With a 10-year difference we have here a 17dB difference. I am not questioning why I prefer the PA7 !
TEAC : dotted line
PA7 : plain line