Hello all,

I thought some of you might be interested in this. A few of us in the UK run Alpine 9887R head units which have the self contained Imprint facility. Unfortunately, in order to use it, you need the KTX-100EQ Imprint kit, which costs extra.

As I have one of these kits, I thought it would be good to share its facilities with the other guys, in order to improve their sound. Everyon who's heard Imprint in operation in my car has been mightily impressed with the positive difference Imprint has made (see my sig for details of my kit).

Anyway, we had a mini-meet today to setup the Imprint in 4 cars and I've posted the graphical results below, as they are quite interesting and may help others with tuning their systems.

Mine



Next up, PaulF who has only upgraded the head unit and is running stock components in his MY02 car



and Paper Lawyer with his 2 channel Genesis amp and Boston Components



We then tried to see if we could load up a "roof open" and "roof closed" setting for unclefester's car. Sadly this didn't work, but here are the two sets of measurements:

Roof open



and roof closed



As you can see, there are a few common peaks and troughs. A trough at around 500Hz, a peak at around 1 - 1.2Khz, and then a sharp peak at around 1.8 - 2Khz. There is a general brightness to the higher frequencies (probably caused by the tweeters firing straight at the windows).

This may help some with tuning their systems if they have parametric EQs.

Of course, what these graphs don't really show is the massive improvement in soundstage and, very usefully, the ability to play music seemingly louder, which is helpful in an open topped car.

We also found that the "Reference" curve worked best with roof and windows up, and the "Reference with Mid-Range Comp" gave a nice boost to the mid-high frequencies and worked very well with roof and windows down. The Windows, in particular have a significant effect on frequency response.

I hope some of you find this of interest

 

interesting to see where our stereo dips and jumps. thanks for posting!

 

I know it is kinda old, but I have been very busy in the past few months. Is it possible to send me these screen captures? I'd like to come up with a general tuning guide for S2ks by studying the common peaks and dips of these measurements

My experience with Imprint so far is that it helps tremendously with mainstream and compressed music(my mp3 sounds amazing now even without a sub!), but it distorts the sound stage "VERY BADLY" when fed with very well recorded material. I think it would be beneficial to all alpine owners if we can come up with one general manual setting for well recorded music

 

claus, I was going to link this thread to your latest post in the "systems" thread.

You're probably best off just downloading the images direct from the links here, i'm not sure the "originals" will be any better, but feel free to PM me if you want them in some other way.

Simon

PS we're going to be doing it again on the 21st as we're installing components and a sub into PaulF's car, and unclefester has finished system too, so that'll need redoing.

Will add the screen grabs for your database.

 

np I'll just d/l what you have

 

No worries, I'll get the new screendumps up next week.

I'll be interested to hear your thoughts.

 

somewhat related question: i have this deck with an Alpine MRP-M650 and 10" Type R sub but stock speakers. would it be worth it to get this done now by a professional or should i wait until i've upgraded and amplified the speakers?

 

Hi Matt,

If you're having to pay for the Imprint runs to be done, then wait until all the kit is installed for the best results. It does depend on what the time frame for the new amp and speakers is. If it's over a year, then it may be worth it, but if you're going to do it in a few months' time, just do a manual tune up using the time alignment and parametric EQ that are already on-board the 9887.

claus, due to there being some snow and lots of ice everywhere, our mini meet has been postponed for the time being. I'll post up the results when we eventually get the install done.

 

So it looks like the imprint really works!

I don't know how the programming works, can the head be set for three different curves (open windows down, windows up and top up) with an imprinter and then it can be removed? Or do you have to have the imprinter hooked up all the time?

Thanks!

 

UPDATE: Next meet is 28th Feb, more curves to come!