Don’t know if i have the same, they had metal dustcaps that gave them a significant screech — i removed them. In th egive away pile (if i can find them) but not well matched.
dave
Given the highish output impedance of the ACA you want to look for a loudspeaker that has a fairly flat impedance curve or like the Fostex FExx6 and FExx8e∑ that are designed specifically for use with highish output impedance amps.
FRs are a good choice due to their often flattish impedance (except at resonance. XOs all too often cause wild impedance curves — for instance Klipsch are often suggested because of their high sensitivity (althou specs typicall some 3dB higher than reality), due to no care with impedance, the XO causes horrific impedance spikes and are not suitable.
Once you sort the impedanc efficiency is not as critical as you might think. I used one of the 1st 5w ACA for a lonng time on my 87 dB speakers with no issues except the rare times i wanted to turn them up. The 18w from the SIT-3 i now have is more than suffieneny, but bridged ACA (with 2x the output impedance) had issues with bass control, i expect, but untried, that parallel would be better for more power.
dave
FRs are a good choice due to their often flattish impedance (except at resonance. XOs all too often cause wild impedance curves — for instance Klipsch are often suggested because of their high sensitivity (althou specs typicall some 3dB higher than reality), due to no care with impedance, the XO causes horrific impedance spikes and are not suitable.
Once you sort the impedanc efficiency is not as critical as you might think. I used one of the 1st 5w ACA for a lonng time on my 87 dB speakers with no issues except the rare times i wanted to turn them up. The 18w from the SIT-3 i now have is more than suffieneny, but bridged ACA (with 2x the output impedance) had issues with bass control, i expect, but untried, that parallel would be better for more power.
dave
The ACA itself doesn’t vibrate, but it may be closer to the speakers than a separate preamp. It also needs ventilation and cooling slots in the top and bottom plates. The B1 Korg is best enclosed in a heavy solid aluminum chassis with no ventilation holes. It also needs to be suspended by vibration absorbing materials. I housed mine in a Naim NAC 62, powered by a separate HiCap PSU. Mine had no problems with oscillation.
I have several pairs of smaller Klipsch bookshelf speakers that work and sound wonderful with my single ACA, so that's simply not true of all Klipsch speakers...
Apologies if this is a repeat but for fun, I plugged the bill of materials published in Nelson's article into Octopart.
And the attached is an export (just change the file extension to .csv and you're good to go).
All of Nelson’s original components appear to be available from what I can see, except for C1. However, Digikey list various substitutes:
P6596-ND
So, you shouldn’t have an issue. At least you can confirm all the specs and dimensions, including PCB pitch.
Enjoy ..
And the attached is an export (just change the file extension to .csv and you're good to go).
All of Nelson’s original components appear to be available from what I can see, except for C1. However, Digikey list various substitutes:
P6596-ND
So, you shouldn’t have an issue. At least you can confirm all the specs and dimensions, including PCB pitch.
Enjoy ..
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ACA with Korg B1
Its not too much of a squeeze, most challenging issue is fitting the volume pot to a 10mm thick front panel. It does make a very neat integrated and I haven't experienced any heart or vibration problems. I do use separate power supplies for
the Kong and the ACA, mainly so that I can turn the ACA off and leave the Kong on constantly. In my case a single source amp is fine...tried to attach images but failed miserably. It all fits in a 2U ACA Dissipante chassis
Its not too much of a squeeze, most challenging issue is fitting the volume pot to a 10mm thick front panel. It does make a very neat integrated and I haven't experienced any heart or vibration problems. I do use separate power supplies for
the Kong and the ACA, mainly so that I can turn the ACA off and leave the Kong on constantly. In my case a single source amp is fine...tried to attach images but failed miserably. It all fits in a 2U ACA Dissipante chassis
Keratherm Brown
I purchased some Keratherm Brown insulating pads as they were readily available in the UK. However, they are not easy to use because they are so, so thin (overall thickness 0.27mm with the plastic protective sheet being 0.02mm thick). I just can't seem to peel the sheet off.
Looking further into this product, it is also inferior regarding its' thermal conductivity, only 1.4 W/mK compared the the Keratherm Red 6.5.
Wondering if anyone has successfully used the brown or whether it would be best for me to get some mica and paste instead?
Graham
I purchased some Keratherm Brown insulating pads as they were readily available in the UK. However, they are not easy to use because they are so, so thin (overall thickness 0.27mm with the plastic protective sheet being 0.02mm thick). I just can't seem to peel the sheet off.
Looking further into this product, it is also inferior regarding its' thermal conductivity, only 1.4 W/mK compared the the Keratherm Red 6.5.
Wondering if anyone has successfully used the brown or whether it would be best for me to get some mica and paste instead?
Graham
Here's an idea; Since Keratherm is so thin, it may help to prepare the mating surfaces by making sure there are no sharp edges or protrusions. Light sanding with very fine sandpaper on a flat surface may be all that's needed to prevent pinched spots.
Edit: And I agree with ZM. Mica is perfect for ACA. That is what I used in my ACA.
Edit: And I agree with ZM. Mica is perfect for ACA. That is what I used in my ACA.
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Thanks guys,
Mica will work for me.
Found a TO-3PL package size (29 x 22mm) that should do the job but I am confused by the description 'mica insulation sheet.....) then down the page, Material-plastic. ???
Thought it best to ask as I don't want to get it wrong again.
Also any special requirements regarding the type of insulating compound?
This all new to me.
Graham
Mica will work for me.
Found a TO-3PL package size (29 x 22mm) that should do the job but I am confused by the description 'mica insulation sheet.....) then down the page, Material-plastic. ???
Thought it best to ask as I don't want to get it wrong again.
Also any special requirements regarding the type of insulating compound?
This all new to me.
Graham