[Calihan]

Anyone used any of the amps on this site 41hz here? I want to get a decent amp cheap for some speakers I will be using for only a little while, hence the cheap amp ^^

The speakers are JBL G300 models, 3 way speakers with 1" tweeter, 5" midrange, and 8" woofer. From the site there, they are 8 ohm speakers, with "Recommended Power Amplifier Range of 10 - 80 watts." That DIY site has many amp offerings, but only 1 that is for 8 ohms. Does it matter if I would use a 4 ohm amp for them?

I thought that for impedance, the higher it is the easier on the amplifier it is. So if I used a 4 ohm amp for 8 ohm speakers, they would be able to do it as well yes?

Anyway, I was looking at their "amp4" to use with the speakers I have. Anyone have any suggestions as to other places to get cheap amps?

 

[error401]

I use an AMP5 to drive my Mission 770's, also 8 ohm speakers. They're two-way, with an 8" woofer and 1" dome tweeter. Not sure on their sensitivity, but the AMP5 definitely has enough power for them. Personally I think the amp sounds fantastic for the price. Don't underestimate the cost of additional parts though, casework and the transformer can easily exceed the cost of the amp parts themselves.

As far as I've seen, 41hz specs all their amps into both 8 ohms and 4 ohms. You won't have a problem driving an 8 ohm speaker with any of the amps, but the power rating will be lower (e.g. the AMP5 I use is rated 100w into 4R, and 60w into 8R). You'll also be able to use a smaller/cheaper transformer, so take that into account when selecting an appropriate one.

Depending how much power you need, this might be your best option. You may want to look at the Sonic Impact amps too, they're only 15w/channel, but include everything including a case for a very good price and reportedly sound quite good.

 

[Heady]

For a quick and easy solution from 41Hz, I recommend the amp6-basic. It is only about 12W into 8ohms but the sound is good. The only problem is how loud you want the speakers to go.

The am6-basic is very easy to built and only have through-hole components. The required power supply can be a wall wart with 12VDC output, easily obtained anywhere.

 

[J.D.N]

www.audiosector.com

I built the LM3875 Amplifier Kit and sounds great. The power you get out of it is dependent on the transformer you use. I my memory is correct the toroidal im using has dual 35v secondaries and give out a true 50w a channel.

These amps are so so simple to build, but they do sound fantastic. And the price is hard to argue with.

 

[fortney]

Heady,

Would you advise me what is the current drawn by this amp?
What current rating is the wall transformer you are using?

TNX

F

 

[dBel84]

Hi Fortney , I built 2 amp6's a few years ago and if memory serves me they need at least 2A to perform their best. I know it was posted on Jan's site but the original thread is most likely archived. I am sure his recommendation is on the site though..dB

 

[cotdt]

i built the amp5 and it is pretty good, especially for the cost.

 

[Calihan]

I was talking to error401 through pm and he sent me a copy of the instructions for the amp5. They don't look to noob friendly to me. I wonder if I will be able to complete something like that

 

[gychang]

Quote:

Originally Posted by Heady /img/forum/go_quote.gif For a quick and easy solution from 41Hz, I recommend the amp6-basic. It is only about 12W into 8ohms but the sound is good.

I was looking into this, does this have on-off LED?

gychang

 

[AudioCats]

How does the LM3875's SQ compare with the Sonic Impacts or 41Hz's class-T amps', when all are playing around 8W?

 

[FallenAngel]

Quote:

Originally Posted by AudioCats /img/forum/go_quote.gif How does the LM3875's SQ compare with the Sonic Impacts or 41Hz's class-T amps', when all are playing around 8W?

There goes the whole battle between "T-amps" and "GainClones" - the LM3975 chips are used in gainclones and Tripath amps are usually built with T2022 (and equivalent) chips. The usual concensus is that the tripath chips are great for the money, but the gainclones have more "feeling" in them. I'm thinking of building a speaker amp soon, still not sure which path I'll choose; maybe I'll just go with a Beta22 and screw both of them to keep a fantastic headphone amp and use it as a power amp as well.

 

[Heady]

Quote:

Originally Posted by fortney /img/forum/go_quote.gif Heady, Would you advise me what is the current drawn by this amp? What current rating is the wall transformer you are using? TNX F

I am using a Sony notebook computer power adaptor, 12V 3.5A output.

 

[Heady]

Quote:

Originally Posted by gychang /img/forum/go_quote.gif I was looking into this, does this have on-off LED? gychang

No, it does not, it has a sleep mode LED though but I simply use a parallel from the power switch with a resistor in series to power the on-off LED.

Amp6Basic is probably the fastest way to build a good amp. The parts are very easy to solder. Power source can be a simple 12V adaptor easily obtainable. The only downside is if your speakers are inefficient or room is very large, then on some music, particularly orchestral pieces, you can hear the amp is straining.

 

[Heady]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif i built the amp5 and it is pretty good, especially for the cost.

I have an amp5 too and I think it is great too. But it isn't as easy to build as the amp6basic.