Just how comfortable someone we assume to be a DIY newbie might be with the collection of parts and chassis bashing that even the most comprehensive PCB “kits” might entail is I think at least as salient a question as “how much power do you really / think you need”, and “budget?”
The ACA and Neurochrome Modulus 286 kits were a breeze to assemble - the old Bottlehead Foreplay & Paramours, EL 84 mono-blocks, EL84 El Cheapo, and rebuild of Eddie Vaughn EL34 SE, to name a few - not so much.
The ACA and Neurochrome Modulus 286 kits were a breeze to assemble - the old Bottlehead Foreplay & Paramours, EL 84 mono-blocks, EL84 El Cheapo, and rebuild of Eddie Vaughn EL34 SE, to name a few - not so much.
From what I can tell, the ACA is jut an amp. How do you control the volume? I assume you need a pre-amp with this? What is the popular diy option?
ACP+ will be interesting when it hits. The Pass B1. Elekit TU-8200. Shitt has a couple.
I was going to mention that a 5W ACA (ie 1v0) can be made into an 8w ACA with the addiiton of a bug-style R, and 24 V supplies.
dave
I was going to mention that a 5W ACA (ie 1v0) can be made into an 8w ACA with the addiiton of a bug-style R, and 24 V supplies.
dave
I am going to say that there is nothing much simpler than the ACA kits. I built one and liked the sound so much I built a second and now run them as bridged monoblocks. DIY Audio did a great job sourcing parts and the 6L6 videos are unbeatable. And the choice of using a “brick” power supply was brilliant. I would not advise a newbie to build a power supply. I assembled a few little Velleman projects to brush up my soldering before starting the ACA.
But once you get into preamps the number of wiring connections increases dramatically, and if you go balanced the complexity jumps again. Since the OP is looking for desktop, why not just go with the computer’s music source for volume control. And I overlooked the near field listening when I recommended the Dayton Audio driver and Parts Express enclosures earlier. They make a sizable bookshelf speaker, and something in the “mini monitor” size might be more appropriate. But I’d stick with a full range driver.
But once you get into preamps the number of wiring connections increases dramatically, and if you go balanced the complexity jumps again. Since the OP is looking for desktop, why not just go with the computer’s music source for volume control. And I overlooked the near field listening when I recommended the Dayton Audio driver and Parts Express enclosures earlier. They make a sizable bookshelf speaker, and something in the “mini monitor” size might be more appropriate. But I’d stick with a full range driver.
I just bought a used OmniMic with software from a guy locally and will test the drivers. No stuffing surprised me , and I’ll try to let you know what the response measurements show.
What speakers. ACA bridged has ~5Ω output impedance and that is getting into the territory of current amps (particualrily with 4Ω speakers) and th espeakers impedance will start having an effect on the FR.
ACA is wonderful, careful speaker choice gets the most out of them.
1/ pr-built supply means the kit is simplier, and 2/ someone else pays for the CSA/UL/(euro standards) testing.
I have not been a fan og the PE boxes since they discontinued the curved side ones. Almost more work to retrofit the rectangles than to start from scratch. Dayton is PRE’s house brand, and range from quite decent to cheap drek.
Lots of nice 3-4” FRs that make good use for the desktop. Jeff mentioned Alpair 7.3 (he bought sufficient raffle tickets to win those that he probably paid for them. He also has a smaller pair with Alpair 6PeN. FF85/105wk, Alpair 5.2/3, A6.2m, lots of TBs (my experience has been mixed), Daytons, HiVi, Aura (now easiest sourced as a Dayton branded driver), Visaton, Faital (the 16Ω Neo 3” is good and looks to have potential).
dave
Tx. for the advice jfuquay.
Actually, I am not looking for a desktop system, something for my small room, 14 x 14' or so. I think I could put together the ACA, but then I need a pre amp. Do I buy one or try another DIY, like I guess the KORG NUTUBE B1 PREAMPLIFIER. But this may be more of a problem to build and not as well tested. So then I start saying, just keep it simple - get a NAD C 316BEE v2 and be done with it and not worry that something will go wrong with my build.
If you don’t want to build a pre i think this is interesting.
Schiit Audio: Audio Products Designed and Built in California
There is also a cheaper SS only one. Either a passive Pre or with gain from the tube. The active circuit in the less expensive SS verion i am guessing is much like a B1. They also have remote control and a stepped resistor attenuator which is hard to find in a diy project… it is really nice to have a volume remote, and outside of exotic, a switched R attenuator is amounst the best and eliminates potentiometer mistracking.
It should be noted that the ACA does not need a balanced pre to be used in bridged mode.
dave
Schiit Audio: Audio Products Designed and Built in California
There is also a cheaper SS only one. Either a passive Pre or with gain from the tube. The active circuit in the less expensive SS verion i am guessing is much like a B1. They also have remote control and a stepped resistor attenuator which is hard to find in a diy project… it is really nice to have a volume remote, and outside of exotic, a switched R attenuator is amounst the best and eliminates potentiometer mistracking.
It should be noted that the ACA does not need a balanced pre to be used in bridged mode.
dave
The speakers Jeff is holding in photo above are Alpair 7.3 in Carmelized Bamboo plywood Marken enclosures. Seen on the right hand side is similar enclosure with Fostex FF125WK.
I’ll repeat my comment above that for a near-field/computer desktop system the compact form factor class D amps should be considered as well. I’ve used both Topping with USB input - the DAC is not at all hurtful, and certainly better than the sound card in my current Windows PC, and possibly even than my long dead iMac- as well as higher powered YJ.
Dave has spent far more time with the ACAs, as well as a First Watt SIT3 to be able to comment on their merits as well as special considerations. IINM, he’s currently using a Schitt DAC and Rotel pre-amp with his SIT3.
The NAD would be a solid choice for a relatively affordable and quite competent basic integrated, if you don’t currently have/ foresee the need for pre-amp line out or digital input(s). The C328 looks like a great piece, but at a much higher cost.
Decisions, decisions
I’ll repeat my comment above that for a near-field/computer desktop system the compact form factor class D amps should be considered as well. I’ve used both Topping with USB input - the DAC is not at all hurtful, and certainly better than the sound card in my current Windows PC, and possibly even than my long dead iMac- as well as higher powered YJ.
Dave has spent far more time with the ACAs, as well as a First Watt SIT3 to be able to comment on their merits as well as special considerations. IINM, he’s currently using a Schitt DAC and Rotel pre-amp with his SIT3.
The NAD would be a solid choice for a relatively affordable and quite competent basic integrated, if you don’t currently have/ foresee the need for pre-amp line out or digital input(s). The C328 looks like a great piece, but at a much higher cost.
Decisions, decisions
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And you can often find used ones cheap. I have not seen an NAD without pre-out/power in, but some of the newer ones may be deficient. With the jumper one has a pre-amp and a power amp in the same boxes.
After the fact, when i worked his, NAD 3020 owners would come in and buy an active XO and either a Quad 33/PS Audio (their 40w amp) or a DH200 (kits, chris built a billion of them for those that wanted a ready to run one).
one could start there, the amp will be good for bass, and add something like an ACA or a small tube amp to extend the system to WAW.
dave
Not a billion, but certainly several hundred, along with dozens of various model of Hafler pre-amps.
Whew, that was a whole lifetime ago -talk about your mid 80’s flashback.
Whew, that was a whole lifetime ago -talk about your mid 80’s flashback.
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The speakers Jeff is holding in photo above are Alpair 7.3 in Carmelized Bamboo plywood Marken enclosures. Seen on the right hand side is similar enclosure with Fostex FF125WK.
I’ll repeat my comment above that for a near-field/computer desktop system the compact form factor class D amps should be considered as well. I’ve used both Topping with USB input - the DAC is not at all hurtful, and certainly better than the sound card in my current Windows PC, and possibly even than my long dead iMac- as well as higher powered YJ.
Dave has spent far more time with the ACAs, as well as a First Watt SIT3 to be able to comment on their merits as well as special considerations. IINM, he’s currently using a Schitt DAC and Rotel pre-amp with his SIT3.
The NAD would be a solid choice for a relatively affordable and quite competent basic integrated, if you don’t currently have/ foresee the need for pre-amp line out or digital input(s). The C328 looks like a great piece, but at a much higher cost.
Decisions, decisions
Yup, the potential options are endless, and hence my paralysis. Probably the best thing for me to do is build my speakers, get a decent integrated amp and see how I like it. Would love to know how good the quality of the ACA is compared to entry level integrated amps like the NAD. If it is much better, then maybe I should give it a try.
Thanks for all the info.
Schiit has a passive amp called the SYS ($49) that is a volume control and 2-way input switch. This seems like this could be a nice fit for the ACA.
No you don't. You simply install a volume POT (potentiometer) on the inputs.
If you have more than one input you can easily add a switch to switch inputs, as well.
Dead simple stuff to add to an ACA, really - and cheap.
On the other hand, I have never regretted buying my pre-amp (HLLY AMK-II) - although I did modify it heavily to meet my needs.
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Late 70s i was working at Victoria’s leadinh hifi shop, while Chris had been working at other ones for longer than me. In the late 70s lots of Dyna, Hafler kits went out the door pre-built for clients (many by Chris).
dave
No you don't. You simply install a volume POT (potentiometer) on the inputs.
If you have more than one input you can easily add a switch to switch inputs, as well.
Dead simple stuff to add to an ACA, really - and cheap.
On the other hand, I have never regretted buying my pre-amp (HLLY AMK-II) - although I did modify it heavily to meet my needs.
This is not a good advice. It will work, but not well. Volume pot on input messes up the feedback in aca. There is reason the pot is not there. You need buffer before aca.
Matt; no uppers, but it was not uncommon to find a cloud of purple haze in the back parking lot at 1532 Pandora Avenue during a Friday evening listening session - always to my mind a more reliable and affordable if only temporary tweak than anything from the Mitch Cotter/Bruce Brisson catalogues- followed by Mexican at El Rancho on Bay St, and whatever adult beverage I was frequenting at home. Ah, the resiliency of youth. 😀
Either way, built quite a few Haflers during that decade or so, which was what that was about. The 500 power amp was a bitch to manipulate.
yatr98; If trepidatious over the prospect of choosing and building the “right” amp/pre at the start of your DIY journey, I’d be inclined to err on the side of caution and pick a competent piece from a known maker with the minimal required feature set. For a desktop scenario, even the lower real world de-rated power levels of around 10watts that most of the budget class D amps offer would be quite sufficient.
For a greater listening distance, the 20 or so watts that something like NAD’s legendary giant killer 3020 amp/7020 receiver would be a good starting point, and the 316BEE offers at twice that, plus an RIAA input, but no streaming / digital inputs.
It hopefully comes as no surprise that there is no “best” - be it source component, amp topology or power level, or speaker driver type/enclosure configuration. System design is all about the balance / compromise of features/performance maxima and real world practicalities, not the least of which are budget and space limitations.
Either way, built quite a few Haflers during that decade or so, which was what that was about. The 500 power amp was a bitch to manipulate.
yatr98; If trepidatious over the prospect of choosing and building the “right” amp/pre at the start of your DIY journey, I’d be inclined to err on the side of caution and pick a competent piece from a known maker with the minimal required feature set. For a desktop scenario, even the lower real world de-rated power levels of around 10watts that most of the budget class D amps offer would be quite sufficient.
For a greater listening distance, the 20 or so watts that something like NAD’s legendary giant killer 3020 amp/7020 receiver would be a good starting point, and the 316BEE offers at twice that, plus an RIAA input, but no streaming / digital inputs.
It hopefully comes as no surprise that there is no “best” - be it source component, amp topology or power level, or speaker driver type/enclosure configuration. System design is all about the balance / compromise of features/performance maxima and real world practicalities, not the least of which are budget and space limitations.