Pyle PTA4 Mini 2x120 Watt Stereo Power Amplifier
Pyle PTA4 Mini 2x120 Watt Stereo Power Amplifier is rated out of 5 by 2.
Rated 4 out of 5
from Nice little amplifier and good controls featuresi bought this to replace another Chinese amplifier from Parts Express that didn't have bass and treble tone controls, both had about the same output power, BTW way over stated, two times 120W, no way in fact 20Watts per channel is not correct either. But is sounds fine for my PC audio and my SDR tuner.
Date published: 2014-11-12
Rated 4 out of 5
from Pretty Good Little AmpAfter playing with several of the Lepai 2020A+ amplifiers I was taken back when I received the PTA4. You could fit four 2020's in the PTA4 enclosure and the PTA4 is very heavy by comparison – it just feels solid. This weight is due primarily to the large transformer used in this amp. Its label says it's a 17 Volt secondary but no current rating is given. It looks like it would easily deliver 4 Amps continuous. This transformer along with a large heat sink take up half of the amplifiers enclosure volume. After rectification and capacitor input filtering the available voltage to the power amplifier section is 23.75 Volts with no load which could sag to about 18 to 19 Volts at full load which is expected and normal.The PTA4 uses an IC amp on the output but without some serious disassembly I could not determine the IC identification since there is a metal clamp across the branding. This clamp holds the IC securely to a very large extruded aluminum heat sink as I mentioned. This amp looks like it could take some serious abuse and still keep going. Just under the clipping point and with a 1 KHz sine wave input the amp measures 18 Watts RMS into 8 Ohms and 25 Watts into 4 Ohms both channels driven. It always annoys me that some manufacturers like Pyle are going back to the over inflated power ratings for their amps. I thought we did away with this practice back in the 70’s. How Pyle comes up with a 120 Watt rating is beyond me. The truth is in the measuring as I found.Frequency response at 1 Watt is -3 dB at 20 Hz on the low end which is somewhat disappointing and -3 dB at 25 KHz on the high end. I would have expected flat response to 20 Hz. The bass control is centered at 50 Hz (not 100 Hz as Pyle states) which I think is a good design choice since most speakers can use a little help below 40 to 50 Hz. The treble control begins its rise at 10 KHz. Both controls are effective and are detented at the center (as is the balance control) for ease in setting flattest response. There is a relay in the amp which delays speaker connection by a second or so at turn on and prevents turn on thump.Feature wise the PTA4 is good at this price point. It provides three line inputs on the rear which are selected with a control on the front panel. There is a 1/8 inch stereo jack on the front panel and microphone input on the rear. This mic input can be mixed with program material and a mic level control is provided on the front panel. I did not test this function. There is no phono input so an external RIAA preamp is needed if you want to use a turntable. The PTA4 also provides a ¼ inch headphone jack on the front panel which is nice. Plugging in headphones disconnects speaker outputs – you can’t have both at the same time. The output level LED’s are blinding – way too bright. They can be disconnected by pulling a small Molex plug on the PC board near the power transformer. I would assume that the LEDs could also be dimmed with a few resistor changes on the display board. I do not have the schematic diagram so can’t point you to what changes to make for this dimming.Using my reference AKG-600 headphones I get respectable sound from this amp but no, it’s not what I would consider to be audiophile quality. I have not yet evaluated the amp on large speakers but do get good sound overall from a small pair of two way bookshelf speakers which use 6 ½ woofers. The PTA4 is a little grainy and bright at upper mid through high frequencies. The bass control is especially effective with these small speakers and the treble control helps to tame the highs.In summary, this is a pretty good little amp and it has some nice features. Compared to the Lepai 2020A+ at around $25 you get more power – the Lepai actually delivers 6 Watts, not the claimed 20 Watts and it has a lot less versatility. Also, the Lepai has only one input and no balance control. I also like the fact that the Pyle amp is self contained – no external power supply which is always on. It’s just one less wall-wart supply to have hanging from the outlet. As I type this short review I’ve been listening to my local analog FM stereo radio station on the AKG-600 headphones and liking the Pyle PTA4 even more.I’ve been dealing with P-E for a long time, their customer service is excellent and l like their 45 day no hassle return policy.
Date published: 2013-04-18