Aktiv Cards for Ninka

The first thing you need is another amp. The 2250 is a two channel amp. You need four channels of amplification for active biamplification of Ninkas (or six channels for active triamplification).

The second thing you will need are stereo Aktiv cards.

There are a variety of ways you can go Aktiv withn Ninkas. Here is the simplest with your set-up.

Buy another two channel Linn amp. Another 2250 would be good since you already have one. However, you could use an LK 85, or an LK 140 as well. Linn amps all have the same gain.

Then put a stereo bass Aktiv card in one amp and a stereo treble Aktiv card in the other amp.

Connect everything together and you're all set. Make sure that the speaker cable is connected to the correct speaker inputs on the Ninkas. Your owner's manual will show you how to connect on the back of the Ninka.

Instead of buying another 2250, you could sell it and buy an AV5125. Then put the stereo treble and bass Aktiv cards in the AV 5125, using four of the five channels of the AV5125 for your Aktiv set-up.

Or, you could keep the 2250, add an AV5125 and three Aktiv cards (one stereo treble card and two stereo bass cards). One goes in the 2250 and the other two go in the AV5125. Now you have a triamplified Aktiv system. Connect to the Ninka as diagrammed in its owner's manual.

There are other possiblities using non-Linn amps but this would involve purchasing a Linn tune-box to hold the Aktiv crossover cards. And then you would have to be careful to make sure that the gain of the other amps matches your 2250.

The simplest thing for you to do is to add another 2250 amp, put a stereo bass Aktiv card in one and a stereo treble Aktiv card in the other.

One other important point to note.

You can certainly go Aktiv using the new Chakra amps; however, the Aktiv cards for the new Chakra amps are not the same size as the Aktiv cards for the discontinued Linn amps. They're not interchangeable. So if you start to mix and match old and new Linn amps, you will have to get the right card for the amp you're going to put it in. When you go to purchase Aktiv cards, it is very important that you specify which amp the cards are for so that you buy the right ones.

As far as sound goes, it is not a small upgrade to go Aktiv. It is a huge upgrade. It will be particularly noticeable in dynamics. Since you mentioned that you listen to a classical music, it would be quite beneficial to go Aktiv since classical music is much more dynamic than other music.

Almaro:

There is no reason why you cannot use the 2250 and the LK 280 together, at least if you use the unbalanced connections on the back of the 2250. Because Linn encourage upgrading through multi-amplification, they make it easier by matching the gain on their amps so that they can be mixed and matched. However, things do change over time, and products change as you go up the chain. So sometimes you have to watch closely.

For example, the LK 280 has a voltage gain of 28.5 dB. If you use the unbalanced connections on the 2250, they have a gain of 28.3 dB. This is not a problem.

However, the balanced connections on the back of the 2250 have a gain of 22.3 dB. This is sufficiently different from the LK 280 that it may be a problem, i.e the drivers connected to the 2250 may sound less loud than the drivers connected to the LK 280, for a given volume setting. It may or may not be a problem. I would suggest sending an e-mail to Linn through their website on this point. They're pretty good in answering questions about their products, although it may take a few days for a response.

So, I see no problem using the unbalanced connections, but the balanced connections might be. See what Linn has to say.

The reason I suggested the LK 85, LK140, 2250, AV 5125, or even the Majik, is that they all have internal Aktiv card slots that will fit the old style Aktiv cards, i.e. the pre-Chakra cards. I do not think that any of the other Linn amps, such as the LK 280 have an internal Aktiv card slot. This means that if you wanted to go Aktiv, you would have to purchase a Tunebox to hold the Aktiv cards, which is an additional expense, on top of the additional cabling required.

Thus, you can passively biamp using the LK 280 and 2250 right now. However, Aktiv biamping would require a Tunebox as well as the Aktiv cards.

By the way, Linn recommend that when you biamp, the better amp should run the tweeters. In your case, use the 2250 for the tweeters and the LK 280 for the mid/bass drivers, although you can certainly switch them around and experiment.

When I went to passive biamplification, I noticed some improvements. First of all, the amps ran a bit cooler since each amp was only powering one set of drivers. I also noticed a slight increase in background detail and better dynamics. However, I did not find the change to be huge and I wondered whether it was worth the extra amplifer cost. On the other hand, when I went to Aktiv, the difference was huge. So you should not judge what you will get in Aktiv biamplification based upon what you get with passive biampflication. I think that passive should just be an intermediary step (probably for budgetary reasons) on the road to Aktiv, rather than a final destination in its own right.

Well since you asked, here are a few random thoughts.

First of all, run the Ninkas passively biamped with your 2250 and LK 280, just to hear what it sounds like to passively biamp. After you've played with this for a while, sell the LK 1 and LK 280/Spark to free up some funds.

Now the upgrade fun begins, as budget permits

I don't know if you are planning to be strictly two channel, or whether you are interested in eventually putting together a 5.1 home theatre for mixed move/music use. Since you have the AV 5103, and since your original post mentions your TV, I have been wondering if a home theatre is ultimately in your plans.

Here are two possibilities.

If you only want a two channel stereo, then add a second 2250 and Aktiv cards. Alternatively, sell your current 2250 (along with the LK 1 and LK 280/Spark) and buy an AV 5125 with Aktiv cards.

On the other hand, if you eventually want to expand into home theatre, here's one (of many) possible intriguing upgrade possibilites.

Sell the LK 1 and LK 280/Spark. Keep the 2250. Buy an AV 5125, and Ninka Aktiv cards. You now have seven channels of amplification. Put the Ninka Aktiv cards in the AV 5125, utilizing four channels. Use the fifth channel in the AV 5125 to power a center channel speaker (eg. a Trikan). Use the 2250 to power two surrounds (eg. Katans, Tukans or Kans). Now you have a 5.1 home theatre with Aktiv left and right front speakers. If you just want music, you use the Aktiv Ninkas. If you want 5.1 movies, you've got that covered too.

Scott, I'm not clear from your post what it is that you want to buy (Aktiv cards for your Ninkas?). Whatever it is, the best used market is right here on Audiogon.