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Crossover mods and speaker efficiancy?

I was just wondering if anyone can tell me if it makes sense that with complete crossover mods(caps, coils, resistors, and internal cabling)that the speakers would draw more current from my amp? My speakers are Hales T5's with totally upgraded crossovers. I am using Dynamicaps for the tweeter section, Dynamicap,Audiocap and auricaps for the midsection and Solen/Axon for the bass area. My coils were replaced with Solo foill coils(16guage for tweeter, 14 guage for mid and 12 guage for bass). Finally as well the internal cabling was replaced with cardas chasis wire of three guages for the three drivers.
My question is that should these changes make my speakers less efficient or draw more current from my amp. I have a Pass X250 which has a meter on it which indicates how much current is being drawn and when the amp is going out of A mode. When the needle moves at all it's out of A mode and into AB mode. What I have noticed with the crossover mod is that the meter is reading that the speakers are taking very much more current than before the mods. The needle bounces to around the 2 or 3 O'clock point on loud passages where as before the mods the needle rarely passed 12 or 1 O'clock. The sound is way bigger sounding and I suppose the bigger sound is due to the larger current draw but I'm not sure. Would this type of crossover mod make my speakers less efficient in that my amp is obviously working much harder than before but the sound is much bigger than before. Any opinions would be greatly appreciated. I should note that I can listen to louder levels of volume of the music as the sound is clean and doesn't sound "loud" as the speakers now tend to have less distortion and I can play loud without being annoyed. The needle on the X250 meter now tends to bounce around alot where as before it just wiggled.
128x128mitchb
sean
6,231 posts
 
The amplifier is actually loading into the speaker better than it was before. The better it loads up, the more power transfer and control that you'll have. After all, the amp can't control the speaker if it can't load power into it in both a timely and efficient manner. The fact that the sound is cleaner even though you are passing more power tells you that the speaker mods were quite worth-while.

As a side note, you're probably experiencing much of what i've been talking about now for several years. That is, the liquid and effortless reproduction at high volumes that one experiences with a true "high power / high dynamic headroom" system. With such a system, the sound doesn't appear to be near as loud as it really is, so you can listen longer with far less fatigue. That's because distortion adds a LOT of "apparent volume" and is very fatiguing. You've taken steps to reduce those distortions via improving power transfer and now you're reaping the benefits. Sean
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trelja
3,223 posts
 
It's great to hear the mods have made such a positive impact in the sound, Mitch!

These mods should definitely make your speakers more efficient. Especially, the inductors and resistors. But, I think the DynamiCaps do this as well, which is why they sound so much bigger and more explosive than just about any other cap out there. TRT goes into some discussion about this on their website, and Peter also will talk about it on the phone a bit.

In my opinion, it just so happens that because your system has improved so much, you are listening at louder, more realistic volumes. This is strictly my own point of view, but I rarely encounter an audiophile who listens anwhere near the volume that I begin to "feel the music". The other day, I was walking during lunch, and a band was playing in the courtyard of a high rise across the street. Even from where I was, the sound was a good deal louder than what most people listen to, and this definitely got me thinking about the high end in general.

I think the increased smoothness, refinement, and dynamics of the modifications have drawn you into the music more, and you are now listening at a higher volume. I think that a good sounding system is much easier to listen to loud, and was one of my major reasons for getting into the high end in the first place.

Incidentally, do you have an SPL meter? If so, set the volume to what you used to listen to, and I wouldn't be at all surprised if your amp reads lower than it used to.
herman
2,259 posts
 
If the speakers are drawing more current (=using more power) to produce the same volume, then by definition they are less efficient. This could be because your mods changed the impedance of the crossover network and more current is bypassing the drivers. The impedance will change unless the new components are exactly the same value as the ones they replaced, and since caps and coils are notorious for having actual values that are quite a bit different from the stated value, this is highly likely. Plus or minus 20% is not unusual. If this is the case, you most certainly changed the crossover frequencies and the resulting increase or decrease in volume at certain frequencies around the crossover points may be what you perceive as being an improvement in the sound.

All crossovers waste a certain amount of power, and your new crossovers may waste more than the originals due to the change in impedance. This is not neccesarily bad if they sound better and the amp has enough oomph to provide the extra current.

The other explanation is as above, you are listening at louder levels without realizing it. This would explain why the sound is "bigger." It's louder so it sounds bigger.

Unless you took measurements before and after the mods you'll never know for sure which it is.
mitchb's avatar
mitchb OP
336 posts
 
Thanks for your responses. This morning at 6 am I decided to listen to music but had to keep the volume down as my wife and daughter were still sleeping and I realised that in fact I am listening at louder volumes than I used to when it doesn't disturb anyone in the house. There is a lot less distortion and the sound in general is bigger. I have been playing my revised Hales now for 90 hours 24/7 and I'm blown away on just how good the system sounds. It truly was like investing in a brand new pair of speakers without taking the loss on my Hales if I sold them. I never thought my system could sound the way it does regardless of tweeks and mods. I am happy and would reccommend this type of mod to anyone but would beware that it could be a gamble and not everyone is happy with crossover mod results. I got lucky!
jond's avatar
jond
5,849 posts
 
Mitch,
Who performed these mods and how much was it? It sounds like a very worthwhile investment and since my Alon's use outboard crossovers it would probably not be difficult to access them, but I'm completely non-handy so I would need someone to do it for me. Of course if you did it yourself I guess I'm out of luck.
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