[FredT300B]

  Cables?

The iPod dock package includes a 1/8" stereo to RCA cable, and the amp has both RCA and 1/8" inputs, so one can use the supplied cable to connect the two components together. For speaker cable I used some 18ga non-OFC speaker wire from Wal Mart. This is not an audiophile system.

[JohnR]

I love it 

[Thomas0322]

Part of the fun of this hobby is putting together an inexpensive system that sounds good.  Fred started out by posting a list of components that people can go out right now and buy.  When it comes to informing someone of the way to put together a musically satisfying (that's relative, of course) system, that's the way to go.

Others posted how they found used components at a good price.  That is also fair to post in this thread.  Still, I think that, to help someone get started with a decent system, it should be things that they can go out and buy right now.

I will add a couple of things.

AMPLIFIER: I have, as part of a computer sound system, the Lepai amplifier that Fred mentioned.  I have played with it in other systems.  Something that I like much better is a little chip amp that I got on eBay.  The power rating is 15 watts, about the same as the Lepai.  I will put a link to the amp below.  This thing is really good when it is mated with a non-switching power supply.  There is a Pyramid 3 amp non-switching power supply available at Amazon and Parts Express.  It takes the amplifier about 3 days to really settle in.  It can sound edgy at first.  Both units run about $35, with shipping included.  So, it kicks up the price a bit.  I think this setup is pretty darn good at a quality level, not just at the bargain basement decent to good level.

CABLES:  I like telephone cable - the relatively newer stuff like cat 5, 5e and, now cat 6.  Perhaps the copper must have a higher purity to handle the high frequency of the DSL service.  I don't know.  It does seem to sound good, and it is fairly inexpensive.  Get cable with 4 pair of internal wires, strip them and wire them together and that gives a pretty fat piece of copper.  I have not compared the difference between the cables, 5, 5e and 6.  The cable can also be had with a Teflon dielectric.


Link to the amp:  http://www.eBay.com/itm/200858211720?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

[Folsom]

I'm going to be trying an experimental power supply with one of these. Who knows what the results will be...  (and I do mean experimental, something I've NEVER seen)

Class D can be Audiophile.

The main things that interfere with the cheaper ones from being very good is usually nothing more than some bad caps and resistors, and the biggest one being the power supply. That is if it's based on one of the better chips.

The system here with a little bit of power conditioning, and maybe a slightly improved source (DAC or something) would be a thrill to listen too. Perhaps it wouldn't score every nuance in the book, but you'd love it.

[bprice2]

I think you might be disappointed with only 15 watts driving the Pioneers. I was.

[FredT300B]

I think you might be disappointed with only 15 watts driving the Pioneers. I was.

Actually it's only about six to eight watts of undistorted power into an eight ohm load, and I'm not surpised you were disappointed. But keep this in mind: The target demographic for this system has never heard of Audio Circle, Stereophile, high end audio, or even the concept of sitting in the sweet spot. He downloads all his music in MP3 format, and never buys CD's. He believes Bose is the best brand. If you told him how much you have invested in your system he wouldn't believe that's possible. He is a music lover with little money to spend on audio equipment. He currently listens to music through his iPod ear buds or the cheap speakers that are integrated into his flat screen monitor. Compared to those "systems", the $132 system will sound Fantastic!

Also, posts like the original often draw two responses on almost any audio forum: 1) How can I build it cheaper without compromising the sound quality too much?, and 2) How can I mod it to get better sound? Good luck on response #1. You can get better sound quality by using a better amp, but not for $25. You can also get better sound, as Tom said, by scoring a flea market vintage component, but that's not practical for the target buyer. Regarding #2, I have found one mod that improves the sound enough to justify the cost. That mod is an upgrade from the included 12V 2A power supply to a 12V 5A supply. It's also a switching supply, and it's a bit pricey at $7.85 from Amazon, but it's worth it. 

The improvement is audibly better bass and the ability to play louder without distortion. http://www.amazon.com/dp/B0023Y9EQC/ref=pe_385040_30332190_pe_175190_21431760_M3T1_ST1_dp_1 

[Thomas0322]

A caveat on my post above:  I am using the little amplifier to break in some Mark Audio 7.3s.  With these high resolution metal cone drivers, the amplifier reveals a more analytic and a harder sound.  My first experience with this amplifier was with paper cone speakers.  That was a better match.

Fred mentioned upgrading the power supply.  I have the power supply that he recommended.  I like the non-switching power supply better.  That does bump the cost. 

Now, I am wondering what low power and relatively inexpensive amplifiers might be out there that sound killer at 5 watts.

[genjamon]

Received my Lepai in the mail yesterday, and the LED lit up, but no sound.  Looks like there's a significant number of people on Amazon reviews for the amp that have had to send theirs back due to quality control issues/non-functional units.  They can be returned easily, but some have said they just buy several at a time to ensure they get one that works and send the others back.  Anyway, I just ordered a second and will cross my fingers no problems with this one, returning the one I got yesterday immediately.  Just an FYI for those interested.

[Folsom]

Build a Felix for the power supply, you'll have a very nice improvement. (slightly cheaper than linear power supply, but a linear can always be thrown in the mix) It'll help reduce the harshness.

The input capacitors on the amplifier board could be replaced for huge improvement (less harsh too). That is if they are accessible, identifiable, etc. Sometimes you just have to remove them (surface mount), bridge the pads, and put your input caps in between the RCA jacks and the board. (when using RCA jacks in a case, and not ones mounted to the board)

I looked around for some pics of inside the Lepai, seems there may have been a few different generations so I can't speak for if the task would be first time solderer, or not.

[FredT300B]

Received my Lepai in the mail yesterday, and the LED lit up, but no sound.  Looks like there's a significant number of people on Amazon reviews for the amp that have had to send theirs back due to quality control issues/non-functional units. 

Using Amazon star ratings as the data source, failures seem to be running about 8%. Of 1,178 reviews, 965 were satisfied (4 or 5 stars). 95 gave it one star.  Most of those complained the amp was either DOA or it failed within three or four months. At the $25 price point you can be certain it's built as quickly and cheaply as possible, with the cheapest available parts and no attention to quality control.   

[Thomas0322]

I said above that I thought the $35 chip amp that I had linked previously in this thread was sounding hard on the Mark Audio 7.3's which I am breaking in.  The power here went off for a moment, and the CD player feeding the signal stopped.  When I turned it back on a few hours later, that little bit of magic that I heard out of the amp was back. 

Now, I am thinking that I was heating up the voice coil and getting speaker compression.  The amp is rated at 15 watts into a 4 ohm load and 10 watts into an 8 ohm load.  The drivers are rated at 8 ohms.  The volume control is set to about the 11 o'clock position.  I would not think that I had been heating the voice coil that much, but it had been playing for hours.

[jqp]

I, too like the idea of this system and the idea of getting some friends and family away from some ipod/pad dock to a real stereo. I am tempted to buy this amp and mod it with the better power supply. Wish there was a Fry's within 5 hours of me, maybe I will order the Pioneer speakers.



Hmmm...  Pioneer SP-BS22-LR 4" Bookshelf Speakers - Black - Pair  are not $77 but &122!

[Wayner]

A caveat on my post above:  I am using the little amplifier to break in some Mark Audio 7.3s.  With these high resolution metal cone drivers, the amplifier reveals a more analytic and a harder sound.  My first experience with this amplifier was with paper cone speakers.  That was a better match.

Fred mentioned upgrading the power supply.  I have the power supply that he recommended.  I like the non-switching power supply better.  That does bump the cost. 

Now, I am wondering what low power and relatively inexpensive amplifiers might be out there that sound killer at 5 watts.

The one thing you are forgetting about is speaker efficiency. A speaker like the Pioneer is about 86db/m/w and with a feeble amp, will drive it to clipping in short order, toxifying the power supply, then bleeding DC voltage to the speakers, which is a speaker killer. DC voltage means no cone movement, just current to the voice coil. That makes the coil heat up, expanding the copper, closing the voice coil gap, and then it is possible for the coils to start rubbing where they shouldn't or worse, start on fire.

Moral of story is that amps of any wattage need to be mated with speakers that have a useable range of efficiency, so as not to destroy the system, which is the road you are heading down.

Wayner

[MLS]

Hmmm...  Pioneer SP-BS22-LR 4" Bookshelf Speakers - Black - Pair  are not $77 but &122!

I paid $77 for mine at Best Buy.

[Letitroll98]

The one thing you are forgetting about is speaker efficiency. A speaker like the Pioneer is about 86db/m/w and with a feeble amp, will drive it to clipping in short order, toxifying the power supply, then bleeding DC voltage to the speakers, which is a speaker killer. DC voltage means no cone movement, just current to the voice coil. That makes the coil heat up, expanding the copper, closing the voice coil gap, and then it is possible for the coils to start rubbing where they shouldn't or worse, start on fire.

Moral of story is that amps of any wattage need to be mated with speakers that have a useable range of efficiency, so as not to destroy the system, which is the road you are heading down.

Wayner

Very good advice on these flea watt amps and a very good description of what happens.  Thanks Wayne.

[Thomas0322]

The one thing you are forgetting about is speaker efficiency. A speaker like the Pioneer is about 86db/m/w and with a feeble amp, will drive it to clipping in short order, toxifying the power supply, then bleeding DC voltage to the speakers, which is a speaker killer. DC voltage means no cone movement, just current to the voice coil. That makes the coil heat up, expanding the copper, closing the voice coil gap, and then it is possible for the coils to start rubbing where they shouldn't or worse, start on fire.

Moral of story is that amps of any wattage need to be mated with speakers that have a useable range of efficiency, so as not to destroy the system, which is the road you are heading down.

Wayner

Wayner,

Let me supply a few more details.  Perhaps that will factor into your analysis.  You mentioned the Pioneer speakers.  I am using Mark Audio.  The sensitivity either way is about the same, so that should not factor in as a difference in your analysis.

The literature with the chip amp specifies 12 volts and 3 amps.  I am using a linear power supply with 12 volts rated at 10 or 12 amps.  I have the volume control pot on the amplifier set to about the 11 o'clock position, about 40 percent of the way to full power.

The speakers were quiet over night.  I took a DCR reading on the voice coils and I got 5.9 ohms and 6.0 ohms.  I then ran the speakers at the previous volume for a few hours.  I took resistance readings again, and the DCR had increased by 0.1 ohm on each speaker.  I checked the temperature by touch on the amplifier and power supply.  The amplifier was just a little warm and the power supply was warm.  As the power supply is a non-switching unit, it naturally runs warm.

I'd like to think that I am not over driving the system.  Perhaps you see something that I do not.  I did not see that I was stressing the power supply.  Of course, you did not have the above information when you made your initial assessment.  Similarly, I'd think that volume set at about 40 percent of full would not be stressing the amp on a nominal 8 ohm load.

The speakers are rated at about 30 watts.  Considering the volume setting and the power of the amplifier, I would not think that I am over driving them.  I did not hear any clipping.  If I did, I'd quickly back off on the volume.

So, in that very subjective world of listening, it seemed that the music just became a little harder and a little drier - just not as good.  Might that 0.1 ohm increase in voice coil resistance do that?  Was it something else?  My take is that I was getting just enough voice coil inefficiency to create that subjective difference in the sound quality.

Thomas

[genjamon]

Thomas, what's the output voltage of your source?  And the input sensitivity of the amp?  You might not need to run the pot to full volume for the amp to reach full output and start going into clipping, depending on the output power of the source, input sensitivity of the amp, and the level of attenuation of the pot.

[Thomas0322]

I should have given information about the source.  It is a Philips CD/DVD player.  I have been running Telarc SACD Sampler 1. lately.  Before that, I was playing Stereophile Test CD 3 (the music selections only, not the test tones).  I got the same compressive effect with both discs. I guess the output voltage conforms to the RIAA standard.  The input sensitivity of the amp is 200mv.

To me, clipping is an audible thing.  The speaker is just breaking up and the distortion is wholly noticeable.  Of course, there can be degrees of clipping.  Still, the speaker starts of in a cold state sounding great at this volume level, and I do not hear any sign of clipping.

[FredT300B]

Lots of helpful comments about this system, and I believe everybody would agree the speakers, in spite of their low $77 sale price, are the strongest link, and the little Lepai amp is clearly the weakest link. This system, as I put it together, will play music unoffensively at moderate volume levels in a small room, but it does leave much to be desired.

Just for fun I replaced the Lepai amp with my $130 Best Buy Insignia 100w/ch stereo receiver. http://www.bestbuy.com/site/Insignia%26%23153%3B+-+200W+2.0+Channel+Stereo+Receiver/9693507.p?id=1218151628383&skuId=9693507&st=9693507 4550834 3720709 3726066 7453327&cp=1&lp=2
If one has the extra $110 I would recommend this upgrade for a variety of reasons, including the adequate power, much better speaker binding posts, AM/FM tuner, and a phono input for later expansion. Replacing the Lepai with the Insignia takes it to a legitimate mass market stereo.

I also connected up a $40 Toshiba DVD player, making it possible to spin 4" polycarbonate disks. http://www.bestbuy.com/site/Toshiba+-+DVD+Player+with+HD+Upconversion/5975875.p?id=1218710591830&skuId=5975875

But this does take the system way out of the under $150 price range, which I believe is important for somebody who wants to listen to music but has little money to spend.

[srb]

I also connected up a $40 Toshiba DVD player, making it possible to spin 4" polycarbonate disks.

That is an odd size disc (4"), in between the 12cm standard disc (4.72") and the 8cm mini disc (3.15") ! 

I know this is all about sourcing a new amplifier as opposed to used, but the fact is I was able to compare driving the Pioneer SP-BS22-LR with both the Insignia NS-R2001 receiver and my Scythe SDA-1100 10W Yamaha-chipped amp, and they were both outperformed by a Denon AVR, at least at medium to higher volumes.

These older used AVRs require little hunting, and are so plentiful that I can find 20 of them at any one time for $100 or less on my local Craigslist.  My used Denon AVR-1603 puts out an honest 75W/ch at 8 ohms and cost $75.

In 5 channel stereo mode it also drives a pair of speakers in the next room with the SL/SR amplification channels (no separate volume control, but the relative volume and speaker sensitivity can be matched with the L/R surround trim).  Its digital inputs also acommodate other coaxial and optical equipped digital sources, but of course not USB.

Steve