Budget T-Amp Shootout - Lepai vs. Indeed TA2020

[Less Opinion]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

They cant do the dishes! I drop one on accident in the sink, it lost it's ability to do anything including swim.

[greywarden]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

My guess is that the difference between your left and right speaker (in an anechoic room) would vary more than that.

Cool to see the very subtle differences though.

[Silver1omo]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

+1 that is good information

[kenrhodes]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

Amazing information thank you, for your work.

[bkeane1259]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

Don Radick got me thinking over on another thread about the measured FR of speakers on different amps. I've never really given this much thought but since I have a bunch of T-amps sitting around, I thought I'd bust out the measurement gear and do some quick and dirty pink noise measurements on a few different amps.

So I used my Marantz 2235b for the benchmark and then also measured the same pink noise on an Indeed TA2021, Lepai TA2020 and Stellar Labs TA2024.

Since this is a "relative test" I just made sure the input signal was the same and the output signal was as close to 2.8v as possible and I kept the speaker and mic in the exact same position for each amp.

Here's all four amps on the usual huge 100db scale at 1/12 octave resolution - no smoothing.



Now, let's zoom in to a 20db scale and 1/24 octave resolution with no smoothing.



Some individual measurement:

Marantz 2235b:



Indeed TA2021:



Lepai TA2020:



Stellar Labs TA2024:



Some one-on-one comparisons.

Marantz 2235b (GREEN) vs. Indeed TA2021 (PURPLE):



Indeed TA2021 (PURPLE) vs. Lepai TA2020 (YELLOW):



There are some minor differences, but I gotta think you'd be hard pressed to actually notice the differences across the amps - speaking strictly about FR. Now dynamics, headroom, distortion, etc......Of course that's a whole different story. Remember, the measurements were made at around 1 watt of output. However, considering the price differential between the above amplifiers I have to admit, I was thinking there'd be more of a difference in the measured FR from a speaker. I was specifically looking for the cheap T-amps to have a large roll-off in the lower octaves, but it's not there. Interesting stuff.

[Silver1omo]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

Double post...

[Silver1omo]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

I'm looking for a cheapish amp and saw these 2:

http://www.ebay.com/itm/2-X-50Watt-Class-D-Audio-Amplifier-TDA7492-/350709620982?pt=US_Home_Audio_Amplifiers_Preamps&hash=item51a7ec20f6

http://www.ebay.com/itm/2-X-15-Watt-4-Ohm-Class-D-Digital-Audio-Amplifier-TA2024-15W-Stereo-Mini-T-Amp-/110932797137?rt=nc&_trksid=p2047675.m1851

I might try the TDA7492...

[bkeane1259]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

The TA2024 chip in the DTA2 and the TA2020 chip in the Lepai/Indeed have just about the exact same power output at 8 watts per channel into 4-ohms.

The DTA2 is only a module, so some soldering and an enclosure are required. All of the above work best with a 12v5a power supply and 4-ohm speakers. If you use 8-ohm speakers then divide your power in half = 4 watts per channel.

Sure, you can adjust your source volume and amp volume so you get the right match, but I find that most sound cards output the best signal voltage when they are turned up close to 100%. Any decent sound card (even embedded sound cards these days) have very low distortion even at max volume. If you start using sound effects and/or equalization, that's where you start to introduce unwanted artifacts and distortion. I'd say DO NOT use any of that crap on the sound card.

With a good sound input, yes, the Lepai will start to distort beyond the half way mark on the volume. However, it's plenty loud at that point with a good pair of 4-ohm, mildly sensitive speakers. If you can, try to shoot for speakers that are relatively sensitive....the more sensitive, the better since you're only dealing with 8 watts per channel. Look for 88db sensitivity or better if you can.

The Indeed TA2020 will have the best sound of the bunch and less distortion when you ratchet the volume, but in a non-critical listening positin like you will be creating, I don't see that there's a benefit to spending basically twice as much for the slight improvement in sound that you're not likely to notice from ceiling-mounted speakers.

[mranim8]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

Thanks Bryan,

I guess I'll get a Lepai and the speakers from PE and check out the audio quality. I thought the DTA-2 amps were too small, or the components start distorting earlier? I'm pretty new to all this.

For the modifications -- I've read that I should set the source volume to between 50% and 75% of max to maximize SNR without distortion, then adjust the volume using the amp. Or at least some sweet spot between source and amp volume to minimize distortion. Is that wrong and I can just leave the volume on the amp at 1/2 (which sounds like the max non-distorted level for the Lepai's), and just adjust the source volume? It'll save me a lot of trouble.

I'll be putting these in an adjoining closet in each room when possible, and in the wall when I can't, so they won't be readily accessible. I'm going to write an app for my tablet to hopefully control all of this (I'm more of a software guy).

[bkeane1259]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

Also, is there a difference between these two Lepai LP-2020A+'s or are they the same insides? older? vs newer?

No difference on the internals.

(Note: I'll be controlling them via a Raspberry Pi and a separate USB audio card. The fun part will be rewiring the amp so I can control the on/off and volume from the Pi itself.)

I'm confused as to how you're going to do this. You're saying you will need to rewire each and every amp so it can be remotely controlled? I have an indeed TA2020 hooked up to my bedroom TV. It stays on 24hr/day at 3/4 volume and I just adjust the TV volume with my cable remote. I'd say if you're going into the amps and doing modifications, you should try a Lepai TA2020 first since it's cheaper and see if your idea works. At low levels, there's really not much of a difference between the Lepai and the Indeed. Once you start to notch the volume up, the Lepai becomes a bit bass shy and also will distort quicker than the Indeed. The Indeed TA2020 sounds robust at any volume level, but you're paying twice as much -- you get what you pay for.

Hope that helps a little anyway.

You might also consider a bunch of Dayton DTA-2 T-amp modules for this project. It's based on the TA2024 chip - outputs almost exactly the same power as the TA2020 chip and sounds identical to the Lepai TA2020, IMO.

[relder]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

Well if the woman wearing those high heel boots is a member of the HiFi club, I certain understand why the club is so popular in China!

Chinese foot binding is still alive and well it appears. (EDIT: oops, responding to a rather old section of this thread)

FWIW the Lepai seems picky as to power supply, I tried an older school one with an actual transformer in it (remember those) and may have roached it, stick with the stock one is my lesson.

[mranim8]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

Hi,

I'm adding a whole house audio system with independently controlled/sourced speakers in each room, totaling 10 pairs of speakers.
Nothing too fancy, just a pair of in-ceiling speakers, probably these or the 8" equivalents.

My question: Will the Lepai be sufficient for my needs or should I go for the Indeed? I can get 10 Lepai's for $160 or 10 Indeed's for $400 (unless there is a better large order deal somewhere) (and about $80 for 10 12V5A power adapters). I won't be listening to the in-ceiling speakers that loudly, but I would like the best quality sound for my very budget setup.

Also, is there a difference between these two Lepai LP-2020A+'s or are they the same insides? older? vs newer?

(Note: I'll be controlling them via a Raspberry Pi and a separate USB audio card. The fun part will be rewiring the amp so I can control the on/off and volume from the Pi itself.)

And if you guys have recommendations for inexpensive in-ceiling speakers that are better than those Dayton's, I would welcome those as well.

Thanks!

[Ron_E]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

I had so much fun with the Tripath amps I decided to build one. ;)

41Hz AMP9-BASIC

It's a kit and it will take awhile to get it and everything it needs together. I'll start a thread when I have something to show. I'll probably mate it with this PS.

24 VDC 8.8A 200W Regulated Switching Power Supply

Ron

[Ron_E]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

That looks perfect for a measurement set up! CD and amp all in one. How do you like it?

I love them. There was a vendor that had a bunch of them on Ebay a few years back and I bought several and encouraged friends to do likewise. Really solid 4 ohm rated amp with tuner, CD, remote with a couple of inputs and sub out. I don't think I paid more than $110 for any of them. I think all the units I bought were new but the vendor had some that had been repackaged. I use one as an external amp for TV and the other gets moved around. It always gets used to check out new builds because it's so portable. I see them used on Ebay from time to time but they almost always want more than I paid for new ones.

Ron

[DanHine]

Re: Budget T-Amp Shootout - Lepai vs. Indeed TA2020

As a reality check I measured my Onkyo CR-325 compact receiver rated at 20W/CH into 4 ohms. It managed 22.5 watts.

[ATTACH=CONFIG]33228[/ATTACH][ATTACH=CONFIG]33229[/ATTACH][ATTACH=CONFIG]33230[/ATTACH]

That looks perfect for a measurement set up! CD and amp all in one. How do you like it?