Problem Solvers Needed-Got my New XOs installed and am worried....

I think I made a big mistake. I loved the sound of my 1988 Tannoy FSM Dual concentric 15'
speakers. So I thought an expert could analyze the existing XOs and make improvements.
I installed the new XOs expecting a 300-400 hour burn in period. Herein lies the problem.

After 30 hours or so the initial sound has no high end to it. I expected to initially hear sound as good as I had
which would continue to improve as the burn in continued. But no. 

I am tempted to reinstall the old XO and kiss off the $2k invested. 

I am very open to some suggestions from anyone who has been down this road.

You forgot the golden rule:  always do a trial of proposed purchases in your own system.  Preferably a long term trial.  Don't buy until you are convinced you like the change.

Amazing how many people read the hype and go out and buy.  One man's meat can often be another's poison.
I sure would like to see a side by side of the two crossovers, (old and new)THAT would tell me a lot.. Any chance you could post a couple of pic in your "details"? If it's lost the highs its a resistor of some type in the HF path.

I'd look where it was hooked to the Highs and see if an inductor or resistor value was added and its GREATER than the original, or as simple as getting the decimal point in the wrong place.

If the HF driver wire was hooked up at the beginning of the HF circuit VS the end of the circuit? That would cause the bass to still be going through the HF side.

A series XO always coming off the + side and on to the next frequency is pretty easy to see the resistance in the path.

Here is the issue I could see in my minds eye. A resistor at the driver that is NOT on the XO. BUT because the resistor was left on or in the HF path the ADDED (but normal) resistor on the new XO doubled the resistance and of course cut the HF signal from getting through.

I would look to see if there is a component that you didn't see or were even looking for. Look at the HF driver terminals and make sure there is nothing in the path and if any type of wiring is going to the Negative side of the driver wire all the way to the new XO.  Just a thought..

If I was the builder though, I would have wondered WHY I had to add the greater value from the old? The light bulb should have gone off.. WHY?
And know a Tannoy XO is not going to be that far off.. IF AT ALL!!

Yet the only customer complaint is "It's Old".  NOT broke.. old...

All I got for no cost. I woke up at 3:30 thinking about that.. And of course it's time to feed the rabbit.. Junior. :-)

Give it 500 hours before drawing any conclusions. Your impressions will continually change during that time.

Play them as much as you can
No worries. If the drivers are OK just go back to the origin values. I would upgrade to better components since you have to do a break in. Did you ask if you have Teflon caps. Maybe they need more time. No permanent damage done just go back to original. Call the person who did the upgrade. If they did require a speacial upgrade he should have told you like Oldhvymec said he had to do on his. I could see why a manufacturer would not put in the Teflon caps. Audiophiles have very little patience. I am a stickler for break in especially on expensive things like audio gear, cars, and motorcycles. It makes a huge difference down the road. We took a road trip and we’re getting 40 mpg in a 2020 CRV touring on the highway. This is not a hybrid. Amazing!
So, about upgrading XOs...

Yes, if you are doing a part swap, then keep the original values. However! DCR in coils and ESR in caps must be maintained, especially in those devices which go to ground, often via a resistor. If you can’t measure that, but only know the uH or uF you are in danger of altering the design. Reducing the DCR or ESR of a part can significantly alter the sound and not for the better. These values are taken into account at design time.

You can’t substitute a generic crossover for a previous crossover. The electro-mechanical properties of the speaker and drivers function as a unit.

There are times when a speaker’s crossover justifies a complete rethink. I’ve seen this in some Focal and Genesis speakers where impedance drops really did justify a reworking here. I’ve also seen actual speaker designer Troels Gravesen post some really interesting write ups on vintage B&W and Yamaha speakers as well. Go take a look there if you want to know how actual speaker designers think about crossovers:

You should be well versed in speaker analysis and crossover design before you attempt this, and even then you must ask yourself, if I’m rethinking this crossover shouldn’t I just build new?

And then... well, if you are building new... lots of outstanding kits out there, not to mention speaker drivers waiting to be assembled into a dream setup.

As always, I encourage DIY and learning about speaker making.  Please do so! Just don't assume things are simpler than they are. :)