I wonder why my front panels ( delivered to the UK ) has no hole for a power switch. I got the switches but nowhere to mount them.
mike
When I went to Modushop to buy that chassis, there was no mention of the ACA special so I bought the same one but with no drilling.
This meant that I've had to drill ALL the mounting holes, front and back, and drill and tap the holes to mount the pcb's to the heatsinks.
It just added to my " I made it myself satisfaction" and has allowed me to personalise it to a degree.
Thanks for the Redco recommendation! Never heard of this company before. I just ordered one of their $10 mystery boxes. We'll see what I get...
Mrudioguru that is exactly what I did. Make sure you get the names of what you get from the cables themselves and get the info about them (insulation, number of conductors, etc...) from Redco's website listings. I ordered two boxes microphone and instruments what did you get? They are also good, and cheaper, for the connectors like XLR, etc... These guys are pros serving the music/entertainement business, they emphasize function not the label of the stuff.
I ordered the mic/line level cable box. I have used Canare and Mogami many times, so I hope I at least get a little of those.
Thanks again for the heads up!
Mike, the kit was available in two 'flavors': with or without the front panel switch hole.
The parts delivered with both options are the same, you still get the front switch, but the chassis is not machined to hold it. You probably selected the 'no front switch' option when you purchased the kit?
Rafa.
OC11, mraudioguru, it's a shame this great divide the water between us affords, as none of the cables you mention ring any bells here.
If anyone here in the UK can suggest a translation it would be handy as I too believe in using the best cables as possible within reason and definitely screened signal cables within the amps environment, which don't seem to have been provided with the kit (or is it not necessary?)
If anyone here in the UK can suggest a translation it would be handy as I too believe in using the best cables as possible within reason and definitely screened signal cables within the amps environment, which don't seem to have been provided with the kit (or is it not necessary?)
This is just my opinion, I have no scientific basis other than function to say so. What you need to do is to find the websites of of cable and accessory suppliers to recording studios and the professional music business in the UK or EU. Once you find them you can find all kinds of descriptions and data on the cable they carry and the uses intended for this cable. The copper they use tend to be the ultra pure kind and many if not all the insulators are PFTE (teflon). Reading their descriptions you can form a good idea of what are the better professional cables in use in the UK and or EU. The names may be different but you can find what you need if you look for it. Of course there is nothing to stop you from slicing the cable up and use the conductors for your own purposes, or choose to use the full cable. You will find a large variety in the number of conductors within a cable, their gauge, and insulation. Have fun.
Semmyroundel, you can find Mogami and Canard cables here in EU too. For instance at Audiophonics.
Try people like 'studio spares' or 'canford audio' for cable by the metre.
EDIT: Semmyroundel, if you just want a foot or so of screened signal cable PM me your address and I'll chuck something suitable in the post for you. I certainly have a spool of Vandamme balanced install cable which is twin core and foil screen in a compact cable. I tend to use the two cores for sign and earth then just connect the screen to earth at the chassis end (be interested if anyone comments on this being good or bad practice?).
EDIT: Semmyroundel, if you just want a foot or so of screened signal cable PM me your address and I'll chuck something suitable in the post for you. I certainly have a spool of Vandamme balanced install cable which is twin core and foil screen in a compact cable. I tend to use the two cores for sign and earth then just connect the screen to earth at the chassis end (be interested if anyone comments on this being good or bad practice?).
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Blew it up it seems
Gents,
I have the strangest thing...
I built the ACA1.6, but since the kits are scarcely available, I built my own, designed single sided pcb's, bought the components and bought a similar case.
When finally finished, I connected all the wires, hooked up speakers and a source and voila, the room filled with music.
So, happy me, job welll done...
So then I proceeded to set the bias... The initial voltage was 6.4 volts, so I needed to adjust it to 10volts.
As soon as I turned the potentiometer, the sound stopped and the light on the psu died...
So I disconnected the power of the channel I was adjusting the bias of and voila... Music again, but obviously only on one channel.
So, I started to adjust the bias on the remaining channel and the exact same thing happened; I now am stuck with a giant paperweight, which short circuits as soon as I flip the power switch...
Anyone have any good ideas, i am stuck...
Thank you in advance,
Cheers,
Neel
Gents,
I have the strangest thing...
I built the ACA1.6, but since the kits are scarcely available, I built my own, designed single sided pcb's, bought the components and bought a similar case.
When finally finished, I connected all the wires, hooked up speakers and a source and voila, the room filled with music.
So, happy me, job welll done...
So then I proceeded to set the bias... The initial voltage was 6.4 volts, so I needed to adjust it to 10volts.
As soon as I turned the potentiometer, the sound stopped and the light on the psu died...
So I disconnected the power of the channel I was adjusting the bias of and voila... Music again, but obviously only on one channel.
So, I started to adjust the bias on the remaining channel and the exact same thing happened; I now am stuck with a giant paperweight, which short circuits as soon as I flip the power switch...
Anyone have any good ideas, i am stuck...
Thank you in advance,
Cheers,
Neel
I tend to use sommer cable for most things studio related, studiospares do this. Its relatively inexpensive too. If I want something fancy and I'm feeling flush I use the glasshouse pure silver solid wire from hifi collective. Apart from possibly silver litz for a tonearm, I'm not sure how a line level conductor could get much better than a solid piece of silver wire. It's certainly the limit of what I'm prepared to spend.
As for xlr connectors, neutrik everytime. Easy to solder and they are bomb proof.
As for xlr connectors, neutrik everytime. Easy to solder and they are bomb proof.
Neel, did you try returning the POT to its original position (before the adjustement)? Does that allow you to power the channel again?
Im sure someone else will come with lots of ideas, but most anyone will ask for pictures to examine the boards for shorts or other problems, so you may just post them in as well!
Start by making sure all the transistors / Fets are in the correct way round and the caps (+ to + and -ve to -ve). Check for obvious shorts in the wiring and Q1 and Q2 are not shorted to the heat sinks etc, also have a look at the resistance checks in the v1.6 build guide (you will have to match your layout to the Pass design) and as Rafa says post clear pictures.
Alan
Neel, I agree with Rafa. If it worked and made beautiful music, leave it as it was originally. You can measure the power you are getting and the level you have adjusted to. Otherwise, I would not find fault with success. If your rig is working at a lower voltage level then it will have less gain, but again as long as your speakers produce good deep music with a good soundstage, why should you care about it?
This was actually my first thought as well. If it worked at around 6.5V, maybe the PSU dies when more current is demanded of it.
Perhaps I should have said as much.
By the way, I would NOT recommend leaving the channels biased at anything but half the PSU voltage rating (19v or 24v). This was just a starting point to assess things.
Perhaps stating the PSUs ratings is the first step
Neel, did you try returning the POT to its original position (before the adjustement)? Does that allow you to power the channel again?
Im sure someone else will come with lots of ideas, but most anyone will ask for pictures to examine the boards for shorts or other problems, so you may just post them in as well!
If i return the pot to its original position the result is the same. The power supply is rated at 24 volts, 5 ampere, so it should be sufficient.
If i connect the amp to a lab power supply, the voltage drops to 1 ,4 volts and the current is 10 amps, the maximum the power supply can deliver, it limits the current at 10 ampere, so the amp is a clear short, my guess is I blew
If I look at the schematic, my guess is there has to be a design error in my pcb, since I can't explain a short otherwise, but I can't find it.
Should I measure the pcb accoring to the supplied overview with all components in place?