Total cost to build a chipamp kit?

sqlkev

Member
2004-03-24 7:43 am
714
This will be my first chip amp project. What would it cost to build a budget kit? (Nothing fancy like all aluminum housing with exotic knobs and parts)

If i buy the "snubberized" power supply kit, I won't need to source my own ps? Would it provide adaquate power for say..50watt/channel?

Go easy on me, as I'm totally new to this :eek:
 
If you buy one of the kits from Brian at chipamp.com you will need the following :

1.) The kit itself.
2.) A transformer. There is a wide range of prices on transformers. Depending on the size and voltage of the transformer you could probably get a decent one for 40-50 bucks. The one that Brian had recomended to me was I think like 42 bucks for a 250VA 25V+25V, or maybe I bought the 330VA 25V+25VA. I am sure others will say you can even go cheaper. www.partsexpress.com has a decent selection of Avel transformers, which is what Brian had suggested to me.

3.) You will need some various parts, like a power cord, a on/off switch, fuse holder, solder, wire, input jacks, binding posts. This stuff won't really add up. You could get all the various stuff you need at a local radio shack, but you can save some bucks and get some better stuff online. partsexpress has most of this stuff as well, as do other places. Probably like 20 bucks.

4.) You will need a case of some sort. I build mine out of wood. Real cheap. If you want a metal case you could probably pick up a hammond case for like 20-25 bucks.

You can probably go cheaper on #3 and #4 on my list, but don't skimp so much on the transformer. You can always go back and move the guts to a better case later on. You can always upgrade your speaker binding posts to better ones. But the transformer is the single most expensive part outside of the kit, might as well start off with one that you aren't gonna want to replace.
 

sqlkev

Member
2004-03-24 7:43 am
714
Thanks for the advices. Seems very logical to get the best transformers. I'll do a bit more research before taking a plunge into this project. Ultimately, I want to do a 6 channel amp/s for an active setup.

BTW, I'm semi local to steve from apexjr.com
http://www.apexjr.com/miscellaneous.html

how are his stuffs compare to the parts from partsexpress?
looks like he got almost everything I would need to build a chipamp, although i'm not too sure about the transformers though.
 
I'm also building 6 channels, decided that building stereo amps was the most flexible/sensible approach for me (only 3 tranformers and power leads).

Today I ordered 1 each of 3875, 3886, 4780 kits. This way I will be able to compare them for myself on passive speakers. With the active 3ways the 4780 will give 120W into the subwoofer.
 
Apexjr has transfos well suited to gainclones. Id probably go dual mono if using those. The misc goods Ive recced for him were just fine.
The capacitors there are a steal. 10,000 uF 63V listed at $1.50, may be offering them cheaper still for diyaudio members.

Parts Express has $5 "28V CT" transfos that are actually 14V dual secondary, guessing VA at 80.
 
sqlkev said:
BTW, I'm semi local to steve from apexjr.com

Steve is a good guy... a stroll thru his warehouse(s) and you can probably walk out with most everything you need for less than ordering new stuff -- and you save the shipping and you get to have a nice chat with Steve.

A real good scrounger can put together a GC really cheap... even buying the boards from BrianGT i have a 4-channel GC that i'm purposely building with as many scrounged parts as possible & it will have cost me less than $100.

dave
 

sqlkev

Member
2004-03-24 7:43 am
714
I'll go through the manual tonight and will start sourcing the misc. parts.

Dave,
I visited Steve once at one of his warehouses, too bad I only got to pick up a few speakers and didn't have time to go through all his stuffs. Will email him soon about this GC project.
 
I built a 2 channel with a 350 VA transformer new from Partsexpress. metal rack type case and a 3/16" aluminum front panel for under $200.
Worked perfectly, and sounds wonderful. Subtract $60 if you find your own case.

Yes it took some time, but I thought that we were here to do DIY Audio..

Why are you here, Bill?
 
I think you are referring to me.

Even though I was just writing about my project, you made me remember that you don't even need a circuit bd.. Something this simple doesn't require a board. Man- I've been brainwashed. I'll bet it sounds quite good even with regular resistors and caps too.
 
LM1875

planet10 said:
I too have a budget 1875 i'm gathering bits for... so far i have trafo, heatsinks, and chips for no cost... going to make it a charicature amp to go with my 50EH5 amp.

dave

It's only a charicature amp until you switch it on.:)

It's like picking a pair of old Philips fullrange drivers from an old radio, stickin' them on a box and...:eek:

Know the feeling?:cool:
 
Speaking of $20 LM1875 amps, I've got one too. The longer you are in the hobby the more parts you collect. Your first amp might be the most expensive one you build. The only parts I had to buy to "finish" this amp were the two switches and an LED.
 

Attachments

  • front right top backsm.jpg
    front right top backsm.jpg
    91.3 KB · Views: 269