Advice on going active

That sounds about right; you'll need a snaic4 to go between the two Hicaps as well I believe. 

The only question I'd have is whether you'd be better improving your source(s) instead of going active. Active SBLs are ruthlessly revealing and are a CD5 and an RP6 really up to the task? I'd suggest probably not. 

Stephen packer posted:

I'm planning to 'go active'.

My current system is:

- CD5 (Flatcap 2)
- Rega RP6 / Audiomods Series 5 / Ortofon 2M Black / Graham Slee Reflex M
- NAC202 (HICAP DR, NAPSC)
- NAP 200
- SBL Mark 1 (recent tweeters)

I've bought a second hand NAXO with power supply so I think all I need is duplicate runs for speaker cables and another NAP200.
I'll be buying second hand and would probably look to buy one of the same vintage as the one I have (give or take).  My existing NAP200 was serviced a couple of months back, so I'd get this one serviced once I buy it.

Am I missing anything?

Thank you.

I feel you Stephen, If an Active System will improve and CD555/552/Ovators 800s 

It should improve an CD5/202/SBLs?

I don't know, but what I do know is I've been Active with a full blown Linn System, and the reason I'm in Naimland, the quest for an Active Naim System!

Check out the following Video, Lawrence  Dickie, Speaker Engineer and founder of Vivid Audio. He prefers Active Speaker over Passive Speakers, but it's just not practical in todays Market.

Before you check out the Video, here are the basic advantages, and disadvantages of Active Systems:

https://www.youtube.com/watch?v=YB_Bp_rR-bk

""Disadvantages of passive systems

It is exactly this progression of the signal described above that causes the main problem of passive loudspeakers (compared to active):
 
• Generally, the high signal streams require massive components of the frequency- separating filters. These massive components inevitably cause distortions and phase shifts. To put it differently: Exactly because the original signal is being amplified before it reaches the crossover network, its components (resistors, spoolings, condensers, etc.) have to be quite voluminous to be capable to withstand the amperage. So, a strong signal hits strong resistances. Inescapably, this signal will be impaired and distorted.
 
• The most important specific deprivation caused by passive filters is the so-called ‘damping factor’. This factor indicates the precision with which an amplifier is able to control the movements of the membranes (of the drivers). A bad damping factor means that the amplifier is not capable of controlling (the vibrations of) the membrane(s) in an exact way. Distortions concerning the sound are inevitable. Up to date high-class amplifier achieve excellent damping factors – but the passive crossover network impairs this factor drastically. To put it simple: In passive loudspeakers, the frequency-separating filters are located in between the amplification and the driver units and necessarily cause a loss of precision with which the amp can control the drivers.
 
The best (and therefore quite expensive) crossover networks available today can reduce this impairment but never avoid it. Even the best ones diminish the damping factor drastically, on average down to five (yes, 5!) percent of the original value!
 
The benefits of an Active Sysrem are obvious, so what are the drawbacks?

Cost is the obvious first one. Given that other considerations such as better amplifiers, sources, etc could improve your system more, this tends to be an end step and therefore at the more expensive end with higher level power amplifiers. One really good power amplifier will sound better than two poorer ones!

Second is the expertise at the manufacturer. To do active properly a company has to be controlling both loudspeakers and amplifiers at a high performance level. There are very few manufacturers that are successful in both markets. 

Currently I think that only Linn and Naim promote active technology in the domestic hifi market, although it is common in pa/concert rigs. It will be interesting to watch developments as to whether the Focal/Naim merger leads to more or less active systems?

This very specialised expertise means that in practice few people will ever own an active system, even thought the rewards are great.""

Hope that information was helpful! 

Allante93! 

Hungryhalibut posted:

That sounds about right; you'll need a snaic4 to go between the two Hicaps as well I believe. 

The only question I'd have is whether you'd be better improving your source(s) instead of going active. Active SBLs are ruthlessly revealing and are a CD5 and an RP6 really up to the task? I'd suggest probably not. 

Thank you.

I guess maybe it would be best to listen to it with the second NAP200 (once I have it!) and decide on whether I go ahead or not.

It's all sounding pretty good (to my ears anyway- are there upgrades for 50 odd year old ears available?) at the moment, if 
going active unbalances it then maybe I can step back...

The CD5 will probably get changed 'in due course', not sure about the RP6, it's had a few mods and the arm's not Rega
anyway.  Maybe...

Allante93 posted:

<snip>

Hope that information was helpful! 

Allante93! 

It was, thank you.  Plenty to consider.

Well, it's all connected up and working.  I'm really quite happy, the 'sharp edges' when drums are hit etc. seem a lot sharper.  Female vocals sound a lot richer.  Of course, it could be that the SBL crossovers had seen better days, but in any case it works  well.

Surprising amount of cabling involved.  Cables everywhere, need to tidy things up a bit, but it's in my office so it's not a priority.

Since the second NAP 200 was second hand (and about 12 years old) it's off for a service shortly, so I'll go back to using the crossovers in the speakers for a couple of weeks shortly. 

Next improvement is probably sorting out a streamer/spotify interface (to replace the existing Sonos Connect unit).

Enjoy your active system. Getting rid of the passive crossover is a big step forward IMO and quite affordable with s/h NAPs. 

Hi,

I would swap out the  power amp SNAICs for two special 'active leads' which you can order from Naim.

With the 200 and below amps (unregulated) this is recommended.

Also having both power amps serviced at the 'same time' is another thing to consider.

From my experience with running a slim-line active system for over ten years i concluded that everything being as closely matched as possible was absolute key to the systems performance and this included the quality of all the solder joints on the four runs of NACA5 too.

Once everything was right though - WOW!!

Thanks, the NAP 200s are within 2 years of each other and one was serviced in February, the other's going to be off for service on Monday.  Regarding the 'active SNAICs' I wonder what the difference is, removing the +24v preamp feed I guess?

The solder joint quality is the same- I did the soldering... So not sure if that's good or bad... (actually it's fairly good)

In the case of the tweeters of the SBL (for which I have the data sheet as my speakers use the same tweeters) Lawrence  Dickie is actually wrong when accounting for the difference of Damping Factor between passive and active; the explanation he gives is only valid for specific (and very unusual) drive units that have extremely low DC resistance.  For most normal dynamic transducers, the crossover has comparatively little effect on inband signals.

Specifically for SBLs and most other speakers...

Scanspeak D2008/851100 have a DC resistance (R_e) of 5.7Ω (value taken from the Scanspeak data sheet).  At the crossover point the impedance of the high pass filter for a Baxandall crossover is at most 1/2 the nominal impedance i.e. 4Ω (and for a L-R crossover it's less, at 1/√2 of the nominal impedance), however this is 90° out of phase giving a vector addition of 2/1.414 in the real dimension.  As a result the effect of the real component on the damping factor is an increase of apparent resistance (rather than impedance) from 5.7 to 5.7 + 2/1.414; so it rises from 5.7Ω to 7.11Ω in the real dimension.  This is a decrease in damping factor of 25% rather than decreasing the damping factor to 5% of nominal (i.e. a 95% decrease).

The reason for the system damping factor being just 5% of the amplifier's damping factor has more to do with the internal resistance of the voice coils compared to the low output impedance of the amplifier, than it has with the crossover.  I.e. it's because of the 5.7Ω DC resistance (R_e) of the Scanspeak D2008/851100, not the crossover components.

Stephen packer posted: Regarding the 'active SNAICs' I wonder what the difference is, removing the +24v preamp feed I guess?

Well yes but the cables themselves are different too plus they're not shielded - AFAIK they're quite reasonably priced or they were.  Well worth enquiring about, it made for a much more stable performance when I used them.