Aktiv Cards for Ninka

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.

Markphd:

Once again I am in your debt for a very informative and helpful response - thank you so much. When I take into consideration the various options you have suggested, including now the mixing of the 2250 and LK 280, I find I am leaning more toward the simplest solution as originally proposed i.e an additional 2250 or .......

As you have indicated, I could use the 280, (provided I pay careful attention to the different voltage gains of each amp), but from your other observations, I tend to see it a compromise, albeit a respectable one and I suspect I would have to eventually move on to somethng more in line with the more simple suggestion above. With this in mind, I think it might better serve my purpose to sell my 280/Spark - I also have the LK1 preamp - to offset the expense of another 2250 - or also sell my 2250 and buy the AV 5125, Activ cards et.al.......(Now if only I had a paper clip I could trade for a new house...!!!!). You have been so very helpful (and patient) and if it's not too presumptive, I would be most apprecitive of any comments or additional thoughts you might have. Thanks again so very much.

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.

Thanks again. I am and will in all probabilty, remain so for the forseeable future, a two channel man, although I may be persuaded sometime to include a centre speaker in my system. So of the various possibilities suggested, the selloff of the LK280 Spark and LK1 together with the 2250 to enable me to purchase the AV 5125 with Aktive cards, would seem to be the best alternative. You have been extremely helpful and I remain so very grateful for the time and effort afforded me. (Note that this thread, once eliminated, was reactivated successfully at my request - thanks Audiogon!)

FYI and interest:
With your 2250 and your LK280 there should be no issue bi-wiring your speakers.

Both of these units have similar plugs for output. Generally speaking,for the sake of uniformity, I would not be quick to mix balanced and unbalanced connections in the same system.

In this case, both units have unbalanced outputs, the LK28 would use banana to banana and the 2250 would use compliance plugs to banana.

This would be uniform and there should be no issues with this match.