New Sequel II owner

Hi,

I have happily been confirmed as human on the 2nd attempt, though using an explanetory email in between.

I have just got a set of Sequel II's, which is the most revealing speakers I have ever heard!

I have found though that one speaker (R in my case) is "duller" than the other. My first action was to bypass the crossover and run full active, as I bi-amp anyway, whith a processor. That brought the speaker back in line.

I then found there is something lacking in their performance, so running my mid-sweeping EQ (I use a 24ch mixing desk as pre-amp) I found that a slight boost arround 3-400Hz improves thbings no end. I then changed my crosover point from stock 250Hz to 300Hz, which made a great improvement.

I have now bypassed speaker 2, (L in my case) as well and crossing at 300Hz, now L is again most prominent, with R getting 3-6dB more than L, for an almost similar responce. I am yet to figure out where the problem lies, though I will soon build a voltage divider to check the HT on both, to see if ther either is higher voltage, as that is the only thing I can think of, but I have not found the schematic of the HT yet, or something else is wrong.

I am feeding them with a 4 ch, 300W/Ch amp.

Regards,
Peet

Have you vacuumed the panels? Showering them might be in order as well.. Those are old speakers and the panels will eventually need to be replaced or rebuilt..

Hi Tom,

my stat panels are SS3UB772(L), & SS3UB773, so I gather they are replacement panels from 2009.

I also understand that they have been re-done (New membranes by a local ML agent) about 3 years or less ago.

So all info available to me indicates that the membranes should be fine, I am not sure how I can check them?

The other puzzle to me is that one is so much less responsive than the other and requires much more power for a similar responce, hence my suspecting the HT supply rather than the membranes.

I will vacuum them, that is one thing on my to do list, so far I have been focussing on the sound and listening!

I have now bypassed the 2nd crossover and running L on 300Hz crossover as well, the difference is huge! My hope/thought that the one had worse caps in it's crossover than the other has now been proven wrong, so to find the next!

Regards,
Peet

Definitely it's the electronics, then. You're on the right path.

Hola. The first thing you have to do to confirm it's not the speaker, is to swap them. If the same speakers now placed at the left channel is dull, then you do know it is. If you had changed the panels, in 2009, still you could have a bad panel. Now you have to swap panels and listen. Put a little piece of masking tape to the suspected panel, because you can get confused. If the suspected panel is found, do the washing procedure.

Many dead or dull panels comes back alive with this procedure. If you have a bad PSU, usually the whole stat panel does not work, and there is no sound at all. The panel does not sing at all.

In a very rare occasions, you might have a very weak PSU and it could polarized a little bit ( charge the panel ) and of course, the problem is a dull or very weak sound.

Happy listening!

Swap the panels to see if the panel is the issue if not then swap the HT supplies to see if that is the problem, even then passive crossover and step-up transformer remains?

OK, so I have now swapped channels, I use Speakon connectors, so I could simply swap them around in my rack, rather than physically moving them across the room. I am though more confused, as I cannot decide which one is more lively, it also depends on the music, as I found more base heavy music to be fine, but lighter classical is where I most noticed it. Tonight everything sounds great, so I will leave and enjoy untill I find an anoyence, then try again.

I have completely removed the passive crossover from the signal path, so my low amps go straight in to the woofers, my high amps go straight in to the transformers. The amp should be fine with the inductive load, I may add some resistors at a later stage, if I change amps to something less capable.

The only original items I would like to look to upgrade is the transformers - anyone know the correct ratios, or a recommended upgrade?

One big snag is I am unable to listen to any of my records unless I have washed them! My previous system still played them fine with just a good brushing, so my collection is receiving som impromptu cleaning.

You might want to play some test signals such as sine wave from 1kHz up or pink noise to more easily identify any SPL or THD differences between speakers.

I often wish I had a SPL meter available. I sometimes considder a cheap one, just to at least have an indication. I suppose I could listen to a sweep, but it would not be a definitive.

One interesting thing could be to run a sweep, with one channel inverted to hear where the peaks are.

If I had my old scopemeter I could run a FFT on pink noise, to get relative responce - done that a few times, but alas I no longer have acces to it.

I would recommend you to invest ~$100 ( or more ) for a soundcard and measurement mic. Download REW and few minutes later you can make meaningful measurements and get more than enough data for analysis if in doubt REW has great help file for reference.