See the OP for attaching vintage Harmon Kardon M6351 speakers to the Lepai amp. The speakers have a nice appearance, great full range sound and inexpensive used with the robust Harmon Kardon reputation. Due to the proprietary Apple G4 plug, the speakers are inexpensive used. An easy mod by stripping the speaker wires to fit regular amps. I own all three amps reviewed here as well as three sets of the Apple speakers. All three amps were tested with the same M6351 speakers.
The original Lepai 220+ Tripath amp which used to sell for twenty bucks is no longer in production and more pricey now as used.
Checking the Amazon site confirms that the Lepy LP-2020A-3A Yamaha chip is an alternate replacement for the out of production Lepai LP-220A+. There is also the newest Lepai LP-220TI adding to the confusion; note that there are also a few other Lepai amps in the series as well. The original 220A+ has very loud sound! All have the blue power on light up LED around the volume knob. The tests below are with the "crystal" Harmon Kardon M6351 Apple G4 speakers.
Dana Puopolo on October 16, 2015 wrote:The Mighty T-Amp: You’ll Be Blown Away
http://www.radioworld.com/headlines/0045/the-mighty-tamp-youll-be-blown-away/335646
There is a revolution happening in audio. The days of heavy, hot, power-sucking audio amplification are fast passing, replaced by an era of a new type of digital audio amplifier, the “T” amp. These amplifiers are over 80 percent efficient, are cheap and best of all, sound great. They are available in board form now at places such as eBay, Amazon, Parts Express and MCM Electronics.
What is a “T” amp? The T comes from a company called Tripath Technology Inc. named after its CEO, Adya S. Tripathi. This was the first company to make the integrated circuits that comprise these amplifiers. Their first IC was the Tripath TA-2020, a 20-watt-per-channel amplifier chip. These were used in very small battery-powered audio amplifiers (one in particular by a company called Sonic Impact) and sold in places like The Sharper Image for around $30. T-amp ICs were originally designed to be used inside HDTV receivers because of their small size, low heat, high power and high efficiency. The word quickly went around — these cheap little plastic amplifiers with the big, round volume control outperformed some audiophile amplifiers that were selling for over 10 times their cost.
People were even hauling 12-volt car batteries into their living rooms to power these little amplifiers. I had one of the early Sonic Impact amplifiers and found that with the right high-efficiency speakers, it truly sounded magical. Tripath began making bigger amp chips, but the cat was out of the bag. Soon lots of IC companies were manufacturing digital amp chips, and since Tripath could not compete with the likes of Texas Instruments and the Asian IC manufacturers, it merged with a company called Etelos in 2008, which itself went out of business in 2013.
Desktop soundcard line out comparison with M6351 speakers - Lepai 220A+ Amp vs Lepy 220A vs Lepai LP-220TI
Comparing each of the amps each hooked up to the same M6351 speakers, the Lepy is not as loud as the original Lepai 220+. One of the issues of the original Lepai 220+ when hooked up to the PC sound card line out; it is loud, too loud causing distortion when cranked all the way up. Turning down the volume control on the desktop helps get around this issue for better volume level control on the Lepai 220+. In hooking up the Lepy, the total volume is not as loud allowing better control range of the volume. Setting the control panel volume to maximum allows the Lepy volume knob to be set half way for regular volume and all the way up for blasting sound. Not ear splitting, but enough to drown out a nearby TV turned on. The newest Lepai TI is right in the middle of volume attenuation between the other two amps. On the sound card line out the control panel can be set to two thirds and still get loud volume out of the TI model.
Laptop headphone output comparison with M6351 speakers - Lepai Amp 220A+ vs Lepy 220A vs Lepai LP-220TI
I first plugged in the new Lepy amp with the M6351 speakers into my laptop. It is an improvement and louder then the laptop "tinny" speakers. However, it was not anywhere as loud as the Lepai 220+ amp on the desktop due to plugged in the headphone jack. Swapping amps; the Lepai 220+ plugged into the headphone jack is definitely much louder; again very loud when the control panel volume is maxed out. The newest Lepai TI plugged in the headphone output works well with a compromised mid volume level. The control panel can be set to maximum resulting with the TI model achieving similar loudness of the original Lepai 220+ though the original is still the loudest.
https://www.cnet.com/products/lepai-lp-2020a-plus/review/
The Lepai LP-220A+ amplifier's TA2020 amp chip incorporates Tripath's proprietary Class-T Digital Power Processing technology. This chip was cited by the engineering magazine IEEE Spectrum as one of the "25 microchips that shook the world" when it was introduced in 1998. No wonder Tripath amplifiers have earned a reputation for sound quality from budget-minded audiophiles, and the LP-2020A+'s rich tonal balance won't tarnish that impression.
http://spectrum.ieee.org/tech-history/silicon-revolution/chip-hall-of-fame-tripath-technology-ta2020-audio-amplifier
There’s a subset of audiophiles who insist that vacuum tube–based amplifiers produce the best sound and always will. So, when some in the audio community claimed that an amp based solely on semiconductors delivered sound as warm and vibrant as tube amps, it was a big deal.
The amp in question was a class-D amp concocted by a Silicon Valley company called Tripath Technology. Class-D amps work by not trying to amplify the incoming analog audio signal directly, but instead they first convert it into a train of digital pulses that can be used to switch power transistors on and off. The resulting signal is converted back into an analog signal with a higher amplitude.
Tripath’s trick was to use a 50-megahertz sampling system to drive the amplifier. The company boasted that its TA2020 performed better and cost much less than any comparable solid-state amp. Like most class-D amps, the 2020 was very power efficient; it didn’t require a heat sink and could use a compact package. Tripath’s low-end, 15-watt version of the TA2020 sold for US $3 and was used in boom boxes and ministereos. Other versions—the most powerful had a 1,000-W output—were used in home theaters, high-end audio systems, and TV sets by Sony, Sharp, Toshiba, and others.
Eventually, the big semiconductor companies caught up, creating similar chips and sending Tripath into oblivion. Its chips, however, developed a devoted cult following. Audio-amp kits and products based on the TA2020 and its sister chips are still available from such companies as Sure Electronics, and Audiophonics.
OffGridKindaGuy wrote:http://www.diyaudio.com/forums/chip-amps/290101-lepy-2020a-vs-lepai-2020a-vs-2024a.html
I own both. The Lepy needs more input level to get the same level of output as the Lepai. The Lepy input is attenuated more than the Lepai. IMO, the Lepy sounds better than the Lepai. Standardized line levels can cause the Lepai to go into distortion easily at high volume. Not so with the Lepy. I believe the "+" on the Lepai is a notice for the upgrade of the anti-pop relay.PCBONEZ wrote:I was digging for detailed specs when I found this post.
My take is the "+" indicates it's an actual Tripath chip.
The "+" models all say "Class-T" and the rest say "Class-D".
IIRC Class-T = Tripath only as it's a Trademark thing.
The Lepy 2020A is a Yamaha chip
The Lepai 2020A+ is the Tripath chip.
The new Lepai 2020TI has a TI chip. (And much better SNR than either of the others.)
The Lepai 2024A+ is also a Tripath chip but it appears to be a 'lesser' chip than the 2020A+.
In WRITTEN specs: 2020A+ @ 2x20w / 2024A+ @ 2x15w.
Lepai, Lepy and Lvpin are apparently all the SAME company with Lepy being the newest name. They are ALL "Chinese Junk" as Bare says. Based on Youtube videos that open them up and look at PCB level they often use salvaged parts. Thus difference from one unit to another has nothing to do with the name stamped on it, it is more dependent on where they got their parts that week.
Sounds like I'm talking them down. - NOT! For the cost these are great little amps. Just be advised that it's good idea to check the board and recap and/or resolder if needed. On paper the 2020TI (Texas Instruments Chip) is best but until some 3rd party reviews on it come out, the 2020A+ is probably the best choice and the 2020A second.
Lepai LP-220TI - $25.00
Unfortunately the original Lepai is no longer manufactured with its historic Tripath chip. Unusual that the series have different names such as Lepai and Lepy; yet all the amps look identical alluding to some as possible bootlegs? I really like the original Lepai LP-220A+ due to how loud it is. The newest Lepai TI utilizes a Texas Instruments chip inside which alludes as not the same quality of sound chip as the Yamaha or the reputation of the Tripath amps. However, Texas Instruments do have a long history in calculators, home computer, commercial components and of course the vintage Speak and Spell. Decades of experience in sound chips, the TI TPA3118 amp chip is used.
https://www.parts-express.com/lepai-lp-2020ti-digital-hi-fi-audio-mini-class-d-stereo-amplifier-with-power-supply--310-3000
The famous Tripath TA2020 amp chip gives the Lepai LP-2020A+ its heart and soul, providing the listener with Class AB precision and warmth while maintaining the efficiency of a Class D amplifier. Unfortunately, the Tripath TA2020 is an endangered species ever since the Tripath company was purchased by Cirrus Logic in 2007. The scarcity of this amplifier chip is especially troubling given that it was listed by IEEE Spectrum Magazine as one of the 25 microchips that shook the world.
Tasked with the challenge to develop a successor to the LP-2020A+, Lepai engineers knew they had to design an amp that combined efficiency, sound quality, and value — and they did it. Focusing their design around the Texas Instruments TPA3118 amp chip, they created the LP-2020TI. This new amplifier from Lepai, though it contains no legacy amplifier chips, overcomes its predecessor in both flexibility and performance.
The hook for me in the Lepai TI was reading reviews on the better Signal to Noise ratio. The TI is definitely louder then the Lepy. The original Lepai 220A+ is still the loudest of the three. Due to the "middle volume" attenuation of the TI compared to the other two amps, I could not hear any hiss when the Lepai TI amp is kicked up to full blast, a very solid replacement of the Lepai A+.
Lepai LP-220A+ Amp = Loudest and best for laptop headphone Jack
The best though maybe too loud resulting in distortion when cranked up. Great for low input signals such as headphone jack.
Lepy LP-2020A-3A Amp = Quietest and adequate for desktop sound card line out
Ideal for a sound card or any source that has a strong signal. Too quiet to fully amplify when using a headphone jack such as in a laptop.
Lepai LP-2020TI = Middle of the three amps in volume peak with best SNR
The newest Lepai model, a great compromise of signal noise ratio vs loudness. Great for both sound card line out and headphones.
My preference is still the original Lepai LP-2020A+. Since it is no longer manufactured and now getting pricey, the Lepai LP-2020TI is a great alternate. Even though not as loud, it is better matched for use as a desktop sound card line out or a laptop headphone jack. I would only buy the Lepy LP-220A-3A if hooked up to a sound card line out; a headphone jack is too quiet even when the Windows volume is maxed out.
Since the sound card line out has less initial attenuation, I moved the Lepy amp over to the desktop. The Lepai TI is my laptop amp due to only a headphone output. I'm saving the original out of production Lepai 220+ for any future more attenuated device such as a portable CD or MP3 Player with headphone jack.
Links
Wikipedia - https://en.wikipedia.org/wiki/Class-T_amplifier
Sonic Impact T-Amp - http://www.tnt-audio.com/ampli/t-amp_e.html
T-Amp History - http://www.radioworld.com/headlines/0045/the-mighty-tamp-youll-be-blown-away/335646
Lepai LP-2020A+ CNet Review - https://www.cnet.com/products/lepai-lp-2020a-plus/review/
Lepai LP-2020A+ Amazon - https://www.amazon.com/gp/product/B0049P6OTI?tag=buynowusaselling-20
Lepy LP-2020A-3A Amazon - https://www.amazon.com/gp/product/B00C2P61FO/ref=s9_dcacsd_dcoop_bw_c_x_1_w
Lepai LP-2020TI Amazon - https://www.amazon.com/Lepai-LP-2020TI-Instruments-TPA3118-Amplifier/dp/B071FJF4FF
Lepai LP-2020A+ Mod - http://techtalk.parts-express.com/forum/tech-talk-forum/45432-modding-the-lepai-t2020a
Lepai LP-2020A+ Parts Express - https://www.parts-express.com/lepai-lp- ... y--310-300
Lepai LP-2020TI Parts Express - https://www.parts-express.com/brand/lepai/471
Lepai LP-2020A+ Manual - https://www.parts-express.com/pedocs/ma ... manual.pdf
Lepai LP-2020TI Manual - https://www.parts-express.com/pedocs/ma ... manual.pdf
Lepai LP-220A+ and Lepai LP-2020TI as the replacement