Mike Hanson
Trying to understand...
Start with replacing the boards in your 180 to guage the improvement, then go from there. You can always swap things back, etc.
Adding front-end regulation "later" isn't typically an option, as you need a second transformer and Cap6 module, and usually means you're building mono amps or have a very large case. It doesn't apply if you're upgrading Naim boxes.
The cap6 isn't a regulator board, it just replaces the existing rectifier/capacitor pcb in the 180. This is the facebook post you are referring to I think. That's basically just gone dual mono with the power supply.Thanks for the clarification Mike, I'm confused then, there is a clear photo of the innards of a 180 with two of the minicap modules replacing the original regulator board and a pair of NCC200 modules on the AA Facebook channel, it was in 2016 mind you so it's well old and may not be suitable for the NCC220 boards ?. It's a 180 I am thinking of modifying so it is a full width Naim box right enough.
The cap6 isn't a regulator board, it just replaces the existing rectifier/capacitor pcb in the 180. This is the facebook post you are referring to I think. That's basically just gone dual mono with the power supply.
I understand your confusion. Perhaps I can help a bit:Thanks for the clarification Mike, I'm confused then, there is a clear photo of the innards of a 180 with two of the minicap modules replacing the original regulator board and a pair of NCC200 modules on the AA Facebook channel, it was in 2016 mind you so it's well old and may not be suitable for the NCC220 boards ?. It's a 180 I am thinking of modifying so it is a full width Naim box right enough.
Actually, in the 180, each NAPA board has its own supply. The 180 transformer has two sets of output windings feeding two pairs of reservoir capacitors, one for each NAPA (the preamp supply is separately rectified and smoothed from one of the windings).The NAP180 has a single power supply, which supplies both NAPA boards.
The 180 doesn't really have the voltage overhead to do this without a transformer change. The 250 has secondaries giving 56v dc which is then regulated down to ~40v. The 180 has secondary rails at ~38v which doesn't give a lot of room for regulation.If you're making a NAP180 into a mono, then you can add a regulation module (like the HCR200). (The NAP250 already has that equivalent.)
Thanks, I wasn't aware of that.The above gives a good overview but there are a couple of points that should be clarified.
Actually, in the 180, each NAPA board has its own supply. The 180 transformer has two sets of output windings feeding two pairs of reservoir capacitors, one for each NAPA (the preamp supply is separately rectified and smoothed from one of the windings).
FWIW, you can run the NAPA boards are much lower voltage. For example, I have my old NAP110 boards running in an amp with ±28VDC rails.The 180 doesn't really have the voltage overhead to do this without a transformer change. The 250 has secondaries giving 56v dc which is then regulated down to ~40v. The 180 has secondary rails at ~38v which doesn't give a lot of room for regulation.
There's one point/clarification worth making: I once considered using a separate "smoothed" supply (transformer+recitifier+caps) to directly supply the front end of an NCC2x0 module. I was told that it wasn't worth the cost/trouble, if I didn't also add some type of regulation.If you are going down the monoblock route with a 180 and Avondale boards, running the front end from one 180 supply and the back end from the other 180 supply as mentioned above is a good solution. This can be done with the original supply or two CAP6s as suggested above.
I once considered using a separate "smoothed" supply (transformer+recitifier+caps) to directly supply the front end of an NCC2x0 module. I was told that it wasn't worth the cost/trouble, if I didn't also add some type of regulation.
That's what I getting at, my 180 is standard and unserviced at present, so potentially without the power supply regulation it may be a little more 'exciting' than the 250. So I am left wondering about what to do with regard to upgrade path one the 180, my worry is that I will potentially lose that excitement if I mess around too much with the power supplies, maybe better to just replace the existing boards with NC200/220s and leave the rest as it is ? I have two 250s with less than 200 hours on since they were last serviced in around 2006 so well overdue for servicing too, and since they already have the regulation it may prove better VFM and improvement in sound to replace the regulation with some HRC200s and a Cap6 and maybe upgrade the amps with NCC220s.
I have been looking at Avondale replacement modules for years now and never had the nerve (or time and the money) to do anything about it, so I am keen to make the right decisions this time. I have the offer of some used NCC200s, HCR200s and a Cap 6 hence my thinking about where best to utilise them in my systems. Got to admit I am also seriously considering some of AA's other offerings, would love to try a Grad1 pre-amp sometime, or some of Les's passive SBL crossovers (I'm also left wondering if he can improve a NAXO 2-4) for an active option.
Lastly, you mentioned the 140 (my first ever Naim amp), what is the best upgrade for that, I'm asking because I may be in the position to help out a fellow Naim owner in Thailand (I introduced him to it over 10 years back) who has no technical savvy and has difficulty with servicing etc for his gear. If I could get the modules before I go out to Thailand this year (April) I could fit them for him and so upgrade and service all in one.
Please keep coming with the information, it's great to be able to take advantage of experience by others who have already dipped their toes in the AA pool.
The point I was making that it needs to be both separate *and* clean. If you're just using a separate supply comprised of smoothing caps, then you might get a slight benefit, but not worth the expense and trouble of that supply. However, if you then regulate it with an Avondale HCR200, VBE, or equivalent, then you see a worthwhile benefit. That's why there are so many Voyagers out there, using the NCC2x0 modules.You might well be right - the NCCs already have filtering and diode isolation from the main power supply so a separate one might not add that much more.
For the NAPAs which don't, I found it had a large impact.
I purchased a s/h NAP250 with NCC220/HCR200 boards to compare to my standard NAP250. The Avondale equipped unit is significantly better in every way!
I’ve also got Avondale crossovers on my SBL’s, a Grad 1 preamp, and TPX2 power supply. All of the avondale kit is an immediate and obvious improvement over the Naim equipment (72/hicap/250) that it replaced!