Hi, I know that this kit isn’t exactly for beginners but I have never put toether an amp before. I’ve completed the kit and am currently sorting out a power supply. However does anyone have any ideas as to what kind of speakers would be best? I’ve heard that you need to get a speaker that can handle the RMS output of the amplifier which will only be 70w at 8ohms(most speakers these days are 8ohms) however would it be better to say get two 35/40w speakers or one 70/80w speaker? I know that I need to have a pre-amp as the guitar is very low gain but I already have a tube pre amp that I will be using for that. Any help on speakers would be much appreciated.
Mat
ps if anyone can find a link to some cheap speakers that would do the job on ebay etc that would be awesome!
It all depends what sort of cabinet you want to make, sealed or vented? The speaker ahould be able to handle more than the amp can pump out to be on the safe side. If you go for the exact amp power you might fry it if any of the subsonic frequencies pass through your amp and clip! Good place to start is Eminence or Celestion, if you go for 2 of these you can connect them to give you 4Ohm eminence-speaker.com/guitar_ … B_CAT_ID=4.
Hi ,
The problem with speakers is that you never can see from the outerside how the condition of the coil is.
I had bought 2 Philips power speakers at the “radiomarket” and there they played very wel.
At home I connected them parallel (8 Ohm + on 8 Ohm + and - to - = 4 Ohm) so I had a combination of 140 Watts.
After screwing up the volume of the CD player and the amplifire , one of the speakers was to tired to play on.
From the outside it looked brandnew.Happily this speaker did cost just 10 euro.The other speaker is still one of the finest I ever had.So be carefull by buying from “somebody” buy a New one and at least some more watts stronger than the amplifire can deliver.You only can give out your money once.:FerdiL
Cheers for the replys. I ended up going for a 90w speaker at 8 ohms for £20 which I didn’t think was too bad. Have finally finished the kit with the transformer fitted. I’ve done as the kit suggests and put a 60w light bulb in series with the transformer to check everything is connected up properly. However the light remains on. I’ve checked all the wiring to and from the transformer and the transformer is brand new so it must be my dodgy soldering. Does anyone know what generally causes the bulb to stay on? I’m guessing that the amp isn’t powering up.
Thanks
Mat
Nowhere on the internet or with the transformer does it tell me what the polarity of the wires out are. The colours are RED, YELLOW, GREY, BLACK. I’ve put Yellow and Black to 30v and Red and Grey to 0v and this produces the lowest amount of humming from the transformer. The red LED is on but only very dimmly. Does that mean I’ve blown a diode or two?
Thanks
Mat
Hi Erickphilips,
I think you didn’t use a magnifying glass to look at the solderingside of the PCB.
If you look very well, you’ll see somepoints of solder that has been splashing.
The best thing you can do is to take a medium hard brush and brush the whole soldering side of the PCB.
After that you try to resolder the connections again and remove the fat soldered points and take time to solder these points again but very properly with a little bit of solder.
Remove directly the splashed flux and look well through the magnifying glass if there is no connection between two points witch dont have to.
Proberly there are one or more diodes defect so that could be a reason why you can hear the transformer.
Test these dam…Sorry things and if you don’t thrust them replase them all by an bridge cell. ( B 80 C5000 or something like that) keep in touch.
Thanks a load for the reply, I finally got it all working. It was a diode in the end.
I’m so impressed of the sound this thing is kicking out. I’m using it with an art tube pre amp at the moment but at some point I’d like to hook up my own pre-amp preferably something with speaker protection or something to stop all the spikes you get from turning your effects pedal/pre amp on and off. Anyone any idea which velleman kit would provide the best solution?
I’ve had a look at some but I’m not sure really what I’m looking for. I’d prefer something without op-amps as apparently that’s why the k8060 works so well also something with massive capacitors to iron out any electrical spikes that might blow my speaker up.
Thanks guys. Everyone is being super helpful.
Mat
In fact is there anything I can do straight away to make it better. Can I just put a large electrolytic capacitor in series with both the positive and neutral audio inputs?
Cheers.
Mat
I think the question you are asking requires quite an involved response so people aren’t bothering.
If it’s any help I am using a K8060 as a guitar amp. I am actually using it with a Celestion guitar speaker and an Boss GT8 effects pedal. On their own it wasn’t loud enough for gigs so I added a simple opamp preamp and it really belts out the volume. All the clever sound shaping is done with the GT8.
Unfortunately, I have tried to add another K8060 to the same chassis and that is where the problems have started!!
Hi ,