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Old 04-07-2016, 02:02 PM   #1
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Default JL 7.7 vs 8.8

Has anyone listened to the 8.8 and to the 7.7's being driven by the same size amp?

The reason I ask is I have a JL 900/5 amp driving 4 7.7's and 2 10" subs, and was thinking about adding another 900/5 amp to max out the power to the same set of speakers. But in talking to a tech rep at JL, he told me that the 50 extra amps going to the 7.7's is barely going to be audibly noticeable for the amount of work involved in adding second amp. He suggested instead to replace the 7.7's with 8.8's, and keep same amp, saying this would give me a 6db gain in volume and would be very noticeable louder and better sounding.

I would like to hear from folks with experience with both speakers being driven by same amp as to whether this is true or is he just trying to sell me the bigger speakers instead of me using a second amp.

I also would need to see if I even have the depth to mount those monsters or not. Mounting depth 2" or so deeper.

Thanks.
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Old 04-07-2016, 02:10 PM   #2
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Our previous setup was 2 900/5's and a 600/4 running 8 7.7's. We wanted more output so we just swapped out all the 7.7's to 8.8's. Holy smokes batman what a difference. They are considerably louder than the 7.7's. If you can fit them by all means swap them out.
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Old 04-07-2016, 03:23 PM   #3
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You say being driven by the same size amp, I assume you mean same watts. In reality nobody would do that because the 8.8' can handle a lot more power. I have only one pair of 7.7's left in my boat and only because 8.8's won't fit where they are. They are either side of the helm, and I have 8.8's fore and aft. They are all getting a little more power than the continuous rating and the 8.8's drown out the 7.7's.

If 8.8's fit put them in you will not be disappointed.

Technically Bradv is correct the 7.7's are more efficient 91 dB @ 1 W / 1 m, vs 90.5 dB @ 1 W / 1 m for the 8.8's. Can you hear a .5 DB difference? Doesn't mean they are louder or sound better. IMO only reason to put 7.7's is because 8.8's don't fit, or budget issues.
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Old 04-07-2016, 03:48 PM   #4
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Don't get too hung up on the 0.5 dB efficiency difference. It's the sensitivity at 1 watt which is not at all an indication of how the speakers compare at 100 watts. Also, 0.5 dB is a difference that is below the audible threshold even in a whisper quiet setting.
As you apply more power to the 880 it will play much louder than the 770 and the 880 will give you more output and deeper extension on the bottom end. In that respect the JL Audio tech is correct.
I don't think you will get all the performance from the 880 that you would with more power, although the 100 watts per speaker from the 900/5 is definitely stronger than amplifiers with the same power rating.
The M770 (not the MX770) is just about as balanced and as musically accurate as you can get. And it has good midbass to mesh well with the subs. It's very hard for larger two-way speakers to ever sound as good as their smaller counterpart through the mid and high band even though they will play much louder and deeper. Some of the 880 bass extension won't be realized when used in the highpass mode, given that you have subs.
If more output is all you are looking for I guess it's worth considering the jump to the 880s.
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Old 04-07-2016, 06:54 PM   #5
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I have an M800 amp bridged powering two sets of M880's for 200 watts to each speaker. They are incredibly loud and clear at less that 1/2 volume and bass is very good at least in my application with the music I like ( classic rock) . When setting up and adjusting levels I played some rap music with a heavy beat and I was afraid I'd crack my gel coat. So base in my application is more than enough. My set up is a compromise due to space constraints ( not room for a sub) and was advised to go with the M880's. I'm happy with what I have. David makes a very good point about the 770 and since you have the sub the 880's may be overkill.
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Old 04-07-2016, 07:32 PM   #6
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Quote:
Originally Posted by pas View Post
You say being driven by the same size amp, I assume you mean same watts.
Yes, I mean that the current MHD900/5 amp that is currently driving the 7.7's would be driving the 8.8's if I changed them out.
So with no change in the amp or the watts it pumps out, the tech I spoke with today was saying for example that if I had the tunes cranking out at 70 watts output from the MHD900/5 using the 7.7's, then change them out to the 8.8's and played the same tunes at the same 70 watts from the same amp, the audio would be much louder to the human ear.

Does that sound right?
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Old 04-07-2016, 07:57 PM   #7
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bradv, David Analog, Rfrasc, pas -

Let me ask you guys this - in your opinions based on your experiences, would be worth the expense and work installing a second 900/5 amp, and via bridging increase the power to the 7.7's to their rated max 150 watts from the current potential 100 watts going into them, OR,

assuming I can fit the 8.8's, change out the 7.7's to 8.8's but running only one 900/5 amp as currently installed - would this give a worthwhile improvement? OR,

are the 8.8's only worthwhile if I also do the second amp and do some bridging to increase the power to their max?

If it's not a real noticeable improvement to keep the 7.7's and drive the power up to their rated 150 watts, I'll probably wait till this coming winter to make any changes.

Thanks
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Old 04-08-2016, 02:19 AM   #8
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I don't recall reading what 7.7's you have, mx or m's? I went from mx 7.7's to m8.8's. I noticed a difference using the same set up 8.8's were louder then the 7.7's. I then bridged my amp for more power to the 8.8's and that was a huge difference. If you can fit the 8.8's make sure you give them plenty of power other wise your wasting your $ in my opinion.
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Old 04-08-2016, 04:17 AM   #9
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Originally Posted by Buttapollock1010 View Post
I don't recall reading what 7.7's you have, mx or m's? I went from mx 7.7's to m8.8's. I noticed a difference using the same set up 8.8's were louder then the 7.7's. I then bridged my amp for more power to the 8.8's and that was a huge difference. If you can fit the 8.8's make sure you give them plenty of power other wise your wasting your $ in my opinion.

Sorry about that, they are M series.
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Old 04-08-2016, 06:26 AM   #10
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Quote:
Originally Posted by vc View Post
bradv, David Analog, Rfrasc, pas -

Let me ask you guys this - in your opinions based on your experiences, would be worth the expense and work installing a second 900/5 amp, and via bridging increase the power to the 7.7's to their rated max 150 watts from the current potential 100 watts going into them, OR,

assuming I can fit the 8.8's, change out the 7.7's to 8.8's but running only one 900/5 amp as currently installed - would this give a worthwhile improvement? OR,

are the 8.8's only worthwhile if I also do the second amp and do some bridging to increase the power to their max?

If it's not a real noticeable improvement to keep the 7.7's and drive the power up to their rated 150 watts, I'll probably wait till this coming winter to make any changes.

Thanks
if youre considering the expense of another amp, have you considered the SD6 from wet sounds? have replaced 900/5 with the SD6 on several boats and saw a noticeable improvement in volume at 180+ watts per channel. im not sure if the sd6 will run 2ohm mono though on channels 5/6 to get max power to your woofers, assuming theyre 4ohm. it would be worth a phone call to wet sounds tech, as the installation would be much simpler than adding a second amp. you could also sell your current 900/5 and cover a portion of the SD6...
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Old 04-08-2016, 07:39 AM   #11
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Originally Posted by mikeym View Post
if youre considering the expense of another amp, have you considered the SD6 from wet sounds? have replaced 900/5 with the SD6 on several boats and saw a noticeable improvement in volume at 180+ watts per channel. im not sure if the sd6 will run 2ohm mono though on channels 5/6 to get max power to your woofers, assuming theyre 4ohm. it would be worth a phone call to wet sounds tech, as the installation would be much simpler than adding a second amp. you could also sell your current 900/5 and cover a portion of the SD6...
interesting looking amp!
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Old 04-08-2016, 08:13 AM   #12
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Yes, the Wetsounds SD6 is an excellent amplifier and will deliver more power in many applications.
However, with the SD6 you cannot bridge into 2-ohms, and running stereo 4-ohms would not have adequate power to drive two M series IB subs. On the lowpass side it would not have near the power of what you have, especially given that the JL Audio amplifier is strictly regulated. Also, the JL Audio 900/5 has dual power supplies so the lowpass doesn't draw from the highpass supply. Sometimes you have to look a little deeper than just surface specs. I can find applications where I would prefer either one over the other, and good design should be application-driven first.
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Old 04-08-2016, 08:21 AM   #13
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vc,
If upgrading to the larger 8.8 then I would upgrade to the second amplifier. After the fact, it's not the most cost-effective way. For four 8.8s and dual 10 subs, an original combo of the MHD600/4 and MHD750/1 would have been perfect.
If not adding the second amplifier, I'm not sure that I would upgrade to the 8.8s....at least for now.
One concern is that you would be pouring money into something that may have inherent problems that have yet to be addressed. Perhaps like the speaker locations and layout, or system tuning. I would recommend that you first get with a JL Audio dealer that can survey the boat with your existing system. Someone who really knows audio and acoustics that can assess if your present system is living up to its potential.
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Old 04-08-2016, 09:20 AM   #14
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Old 04-08-2016, 01:05 PM   #15
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Quote:
Originally Posted by David Analog View Post
Yes, the Wetsounds SD6 is an excellent amplifier and will deliver more power in many applications.
However, with the SD6 you cannot bridge into 2-ohms, and running stereo 4-ohms would not have adequate power to drive two M series IB subs. On the lowpass side it would not have near the power of what you have, especially given that the JL Audio amplifier is strictly regulated. Also, the JL Audio 900/5 has dual power supplies so the lowpass doesn't draw from the highpass supply. Sometimes you have to look a little deeper than just surface specs. I can find applications where I would prefer either one over the other, and good design should be application-driven first.
I am running 4 10" JL IB subs, and 8 JL 8.8's off of one SD6, technically the subs are slightly underpowered getting only 145w each but they still shake the boat. I have run both subs and 8.8s one per channel in the past 185w each and really cannot tell the difference with the current setup. Also where the subs are located is barely able to contain the power of the subs as is. I had originally planned on adding an SD2 to power all 4 subs but I think it will be overkill in my case.
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Old 04-08-2016, 01:09 PM   #16
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Quote:
Originally Posted by vc View Post
bradv, David Analog, Rfrasc, pas -

Let me ask you guys this - in your opinions based on your experiences, would be worth the expense and work installing a second 900/5 amp, and via bridging increase the power to the 7.7's to their rated max 150 watts from the current potential 100 watts going into them, OR,

assuming I can fit the 8.8's, change out the 7.7's to 8.8's but running only one 900/5 amp as currently installed - would this give a worthwhile improvement? OR,

are the 8.8's only worthwhile if I also do the second amp and do some bridging to increase the power to their max?

If it's not a real noticeable improvement to keep the 7.7's and drive the power up to their rated 150 watts, I'll probably wait till this coming winter to make any changes.

Thanks
I think the SD6 is perfect for you. You have two ways to set it up.

one driver per channel subs and 8.8s all get 185w if you find that the subs need more power, then run each sub on a pair of bridged channels with the gain turned down more than usual, and run the 4 8.8's off the other two channels. Or do the same and change the 10" subs for the new 12" subs and it would be killer!
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Old 04-09-2016, 08:34 AM   #17
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Originally Posted by pas View Post
I think the SD6 is perfect for you. You have two ways to set it up.

one driver per channel subs and 8.8s all get 185w if you find that the subs need more power, then run each sub on a pair of bridged channels with the gain turned down more than usual, and run the 4 8.8's off the other two channels. Or do the same and change the 10" subs for the new 12" subs and it would be killer!
I definitely don't have space for the 12" - that's a monster!
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Old 04-09-2016, 08:35 AM   #18
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Quote:
Originally Posted by David Analog View Post
vc,
If upgrading to the larger 8.8 then I would upgrade to the second amplifier. After the fact, it's not the most cost-effective way. For four 8.8s and dual 10 subs, an original combo of the MHD600/4 and MHD750/1 would have been perfect.
If not adding the second amplifier, I'm not sure that I would upgrade to the 8.8s....at least for now.
One concern is that you would be pouring money into something that may have inherent problems that have yet to be addressed. Perhaps like the speaker locations and layout, or system tuning. I would recommend that you first get with a JL Audio dealer that can survey the boat with your existing system. Someone who really knows audio and acoustics that can assess if your present system is living up to its potential.
Probably makes the most sense - to find a audio guy real familiar with boat set ups and let them survey the situation.
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Old 04-09-2016, 08:52 AM   #19
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Originally Posted by vc View Post
Probably makes the most sense - to find a audio guy real familiar with boat set ups and let them survey the situation.
Your JL Audio dealer should be filling that role. However, if he is not the right guy, call JL Audio technical services. They should know who the best candidates are as a marine audio specialist and who is local to you.
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