Passive preamps

I’ve recently discovered passive preamps! Ended up replacing my NAC N172XS with an Icon Audio and Bluesound Node - was meant to be temporary but … complicated story! Would be glad of any thoughts /pros and cons re passive v active from community members.

I don’t have any experience of passive claims, but if you only have digital sources, with a high output, then it would seem to make a lot of sense. A lot of people seem to struggle with Naim preamps trying to control sound level over a very small amount of the volume control rotation, and with shifts in balance when the volume control is close to zero.

The NACs would seem to be the source of the fabled “Naim sound“, so if that is important to you then a passive would lose it (though from my reading of this forum over several years It seems that the “Naim Sound” was more prominent in the earlier preamps, and as the time advanced with higher level ones improving on aspects additional to the primary focus on timing the characteristic sound may have reduced). Also Naim say their power apps are intended to be used only with their pre-empts, so how will that would work with a passive preamp I have no idea. In my case my DAC (Chord Dave, and before ot Chord Hugo) Has a variable level output, well capable of driving a car and direct, so I do it that way, cutting out the “middleman” of a preamp, not having any non-digital sources.

I was always lead to believe that, to attain the true NAIM sound, you needed pre and power to be NAIM: One complements and re-enforces the other. Which, to me, infers any weakness in one part is ‘fixed’ by the other so, combined, they create a whole.

Interesting response, thanks, including re ‘Naim sound’. I’m actually feeling a bit of an impostor on this forum at the moment, as the NAC 172 was the only bit of Naim gear I had! - feeding Musical Fidelity XA50 monoblocks (long since modified by ex Mus Fid amplifier guru Jez Arkless, another story) into IPL floorstanders. As well as the Node, the passive is fed by my Linn Linto phonostage. Both sources sound excellent. Whilst the NAC172 always sounded great, the passive seemed to expose a slightly forward/ringing colouration from the NAC. As it happens, I have just replaced the Icon with a £150 unit from China that uses the same Alps Blue volume pot, sounds pretty much the same but with the convenience of a remote that provides input selection. Actually I don’t care what it has inside when it sounds as good as it does! A mate has just tried my Icon in his system and discovered he prefers it to his Linn Klimax Kontrol. This is all making me wonder why passives aren’t more widely available/mentioned in the hifi press/included in the catalogues of mainstream manufacturers? Are ‘active’ preamps actually unnecessary for many people?

I suspect actives - as in pre-amplifiers are unnecessary for many people - however I suppose it depends what the passive “preamp” is and does. To suit the majority of digital or other high level sources there should be buffered input and output stages, with appropriate input and output impedances as well as input switching and a volume (and possibly balance control), but with unity gain attenuatable to zero (i.e. no amplification) - and not just be a fancy attenuator. I seem to in the early days of CD some “passive preamps” that were no more than input switches and attenuator, but they might not maximise the sound quality of all sources.

Interesting to see someone with IPLs!

I’ve recently started looking at these myself, can I ask which model you went for?


Plenty written on the forum over the years about passive vs. Active preamps used with Naim power amps.

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Thanks - sorry, hadn’t noticed, probably because I’d never become interested in them until now!

Sorry David, I should have been clearer, what model of the Icon have you been trying out

Not sure if your post with the link will be allowed to remain under forum rules

Ah, yes, my IPLs! Wonderful transmission lines with ribbon tweeters. Kits of course. What a bargain for such great sound - deep but tight bass, lovely clean top end. Ivan (Ivan P Leslie!) recently retired alas.

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Sorry, it’s the only passive preamp that Icon Audio make - available with or without remote volume control. And sorry again - didn’t realise I wasn’t allowed to load a link! Was about to load an Icon Audio one! Do the Google and you’ll find it!

Please do not post links to commercial sales sites here. Thanks.

Ok Richard thanks, sorry, wasn’t aware.

Please read through the forum rules. Thanks.

Yes, I was aware of IPL, and of their demise due to retirement (always sad when that happens). Having been hooked on TL speakers since the mid 1970s I looked at them from time to time, and had they made a bigger one I’d have been tempted to buy a kit (actually I considered at one point).

Hi Richard. Thanks for your forebearance. I did skip through them before posting but have just looked again and apologise for missing that one. Have also been looking with interest at previous posts re passive preamps. Can’t pretend to understand the technicalities, but it seems I may have been fortunate to gain such good results in my system without first understanding them! To return to a question in my original post I am wondering whether you might have any comment as to why Naim, along with other highly regarded manufacturers, do not offer passive preamps as a simple alternative to their active ones?

I used a Townshend Allegri Plus for a while after hearing positive reports of it being used in a Naim system. It didn’t sound great to me, so I got rid of it. I now use the digital preamp in my DAC direct into a power amp, but in a Naim system a Naim preamp is what worked best for me.

Coming into this a bit late.
I have been using a Music First Audio Baby Reference TVC passive amplifier for a number of years. My main sources are vinyl (Avid Acutus) and streamer (Naim NDX2). My current power amplifier is PS Audio BHK250 but I have previously used Chord Electronics SPM 1200E, Naim Nap300 with absolutely no issues at all. Being Transformer Volume Controlled (TVC) the amp does not suffer from the same issues of soft bass and compression that can be levelled at some passive amps.

I love my MUsic First Pre and would not swap it for any active pre. It adds nothing and takes away nothing from the signal coming from the source components.

The other passive amp often being used with Naim amps and raved about by some reviewers, is the Townshend Allegri Reference. I have listens to this amp and like it but prefer my Music First audio pre

My experience of passive pre-amps with Naim power amps was generally poor and lacking in life and engagement. Naim power amps are designed to work with their active pre-amps, so I guess my experience was not surprising.

Passive pre-amps really need a power amp that has been designed to work with them. I have an old Sondex pre/power where the pre-amp is passive and the power amp specifically designed to partner it. The combination sounds very good - superb for their time - but try partnering the power amp with a different active pre-amp and it’s noisy and sounds not so great; different horses for different courses…

Of course there are also transformer based pre-amps, which are something else again, and can work rather well…

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