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agarabaghi
05-06-2011, 02:47 PM
So everytime i try to order an amp, its either the wrong one or its not in stock. Probably a good thing that the Pyle 6ch marine amp was not in stock, but now im looking for something to power my tower speakers.

Ive decided i need a marine amp as my JL j2 did not last very long.

So sugguestion on a decently priced amp which will do 300 - 600w / rms x 1 @ 4ohm (full range for tower speakers)...

Or possibly an amp that can do 50 - 100w x 4 @ 4ohm and have a bridgeable channel for the tower speakers to get around 300~ w/rms x1 to the tower speakers...

I saw the syn6 from wetsound but it is slightly over my budget right now

EarmarkMarine
05-06-2011, 03:29 PM
Not exactly sure about your application but if you want a marine fullrange tower amplifier the JL Audio MHD750/1 would make an excellent choice.
A strictly regulated, conservative 750 watts at any voltage down to 11 volts and into a broad impedance range. That's going to be equivalent to an unregulated 1000 watt amplifier when sitting at rest.
60 percent more efficient than a Class AB amplifier so it just sips current by comparison.
This will run four tower JL 7.7s to their full potential and be enough to drive four HLCDs if you ever change over.

David
Earmark Marine

Starshack
05-06-2011, 04:16 PM
JL makes good stuff but my guess is would run you $800+. BTW I think Earmark Marine has being giving very "sound" advice on the forum. I installed a Kicker 5 channel/700 watt marine version over the winter. Sounds great but I don't have any data on durability. You can get them from the discount online stores for under $400. It looking around it seemed to be the most bang for the buck. I am driving 6 Polk speakers plus a Kicker sub.

http://www.onlinecarstereo.com/CarAudio/p_26103_Kicker_10ZXM7005.aspx

agarabaghi
05-06-2011, 04:24 PM
just ordered

http://www.wetsounds.com/pages/products/SYN6_spec.html

Starshack
05-06-2011, 04:31 PM
Nice choice - I am sure you will be satisfied.

rgardjr1
05-06-2011, 04:35 PM
just ordered

http://www.wetsounds.com/pages/products/SYN6_spec.html

I've got the Arc Audio version driving my 4 in boats and sub. I've been real happy with this amp.

agarabaghi
05-06-2011, 04:36 PM
THAT WHAT IT REMINDS ME OF!

Are they same amps?

agarabaghi
05-06-2011, 04:37 PM
I plan on running the 4 speakers with 60 each and the tower with 600 ... thats what the guy from wetsounds said...

Forrest-X45
05-06-2011, 05:03 PM
Not exactly sure about your application but if you want a marine fullrange tower amplifier the JL Audio MHD750/1 would make an excellent choice.
A strictly regulated, conservative 750 watts at any voltage down to 11 volts and into a broad impedance range. That's going to be equivalent to an unregulated 1000 watt amplifier when sitting at rest.
60 percent more efficient than a Class AB amplifier so it just sips current by comparison.
This will run four tower JL 7.7s to their full potential and be enough to drive four HLCDs if you ever change over.

David
Earmark Marine

David - what's the advantage of running 4 tower speakers with a one channel mono block amp versus a 4 channel amp? I am looking to upgrade my tower speaker amp as well. I currently have 4 JL tower speakers and would like to try a more powerful amp before jumping to new tower speakers.

brucemac
05-06-2011, 05:52 PM
just ordered

http://www.wetsounds.com/pages/products/SYN6_spec.html

i have this and am quite happy with it, but a little bummed at my choice now with the intro of the new Rev series 8's and 10's. i am running a pair of Pro80's off of channels 1-4 bridged and then my sub off of 5&6. then a Syn4 to my inboats.

the new Rev 10 (which is the same form factor as the current Pro80) is rated at 400W RMS, so with that said, the only way i could upgrade to the Rev 10's is by running them off the Syn4 and moving my inboats to channels 1-4 of the Syn 6 (not a great option because it would only be 60-70W and my Polk MM's are rated at 125W, OR sell my Syn6 and buy a Syn 4 for the Rev 10's AND a Syn2 or Syn1 for my sub. not crazy about either of those ideas really.

guess i should hook up the inboats to the Syn6 and see how they sound before i beat myself up about it though.

rgardjr1
05-06-2011, 06:09 PM
guess i should hook up the inboats to the Syn6 and see how they sound before i beat myself up about it though.

Do you have 2 pairs of MMs? Maybe run them parallel to the Syn6 bridged. Specs say the Syn6 can do Stereo @ 2 Ohms 305 x 2 watts RMS

brucemac
05-06-2011, 06:18 PM
Do you have 2 pairs of MMs? Maybe run them parallel to the Syn6 bridged. Specs say the Syn6 can do Stereo @ 2 Ohms 305 x 2 watts RMS

i do, but the darn polks are 3.7Ohms :rolleyes: not sure if the Syn6 will handle that. my guess is not. i was going to see if i could catch Tim sometime next week maybe and figure out exactly what my options are.

Jeff d
05-06-2011, 08:13 PM
David - what's the advantage of running 4 tower speakers with a one channel mono block amp versus a 4 channel amp? I am looking to upgrade my tower speaker amp as well. I currently have 4 JL tower speakers and would like to try a more powerful amp before jumping to new tower speakers.

I'm not David and I'm sure my response won't be as detailed and accurate but when you run a 4 channel amp and 4 speakers (Assuming 4 ohms each) the amp will "see" a 16 ohm load. So, it will be pushing about 1/4 of the power that it would if there was just a 4 ohm mono load.

In a tower speaker scenario stereo isn't really important because you're 65-80' from a set of speakers that are only 3-5' apart. There's no way you'd be able to distinguish between the left and right channels. It could actually be a disadvantage depending on how it's setup because if you were out on one side or the other you'd potentially hear one channel noticeably louder than the other if the speakers were angled out towards the flats.

So, if you setup the amp in a bridged configuration with each pair of 4 ohm speakers wired in series (8 ohm load per pair) then wire the two pairs in parallel then the amp will "see" a 4 ohm load and put out much more power (i.e. louder) vs. the 4 channel, 16 ohm configuration.

j.mccreight@hotmail.com
05-06-2011, 09:12 PM
[QUOTE=Jeff d;750709]I'm not David and I'm sure my response won't be as detailed and accurate but when you run a 4 channel amp and 4 speakers (Assuming 4 ohms each) the amp will "see" a 16 ohm load. So, it will be pushing about 1/4 of the power that it would if there was just a 4 ohm mono load.

When you add a "load" ie another speaker the ohm value gets cut in half not added. so if running 4 speakers and each had 4 ohms than the new value will be .5 ohm if all speakers are used on 1 channel very few amps will handle that type of load, my JL M400/4 is 1 ohm stable but i would think running less than 1 ohm would definatly cause thermal overload and cause amp to shut down. also running less ohms will cause more watts to each speaker ie parrallel 2 speakers in one channel equals more watts than 1 speaker on same channel. Less ohms equals more watts. the JL amp that was recommended is Monoblock Class-D Full-Range Amplifier. 750 Watts @ 1.5-4 ohms My JL Audio M400/4 is 75W RMS x 4 @ 4 ohms or 100W RMS x 4 @ 2 ohms or if its bridged 200W RMS x 2 @ 4 ohms

JimN
05-06-2011, 09:35 PM
i do, but the darn polks are 3.7Ohms :rolleyes: not sure if the Syn6 will handle that. my guess is not. i was going to see if i could catch Tim sometime next week maybe and figure out exactly what my options are.

Did you measure the Polks to get that 3.7 Ohm number, or is that how they're rated? 3.7 Ohms is a common DC resistance reading but there's no such think as a speaker that has a constant impedance, which is defined as 'resistance to alternating current" and is different at various frequencies.

JimN
05-06-2011, 09:39 PM
I'm not David and I'm sure my response won't be as detailed and accurate but when you run a 4 channel amp and 4 speakers (Assuming 4 ohms each) the amp will "see" a 16 ohm load. So, it will be pushing about 1/4 of the power that it would if there was just a 4 ohm mono load.

In a tower speaker scenario stereo isn't really important because you're 65-80' from a set of speakers that are only 3-5' apart. There's no way you'd be able to distinguish between the left and right channels. It could actually be a disadvantage depending on how it's setup because if you were out on one side or the other you'd potentially hear one channel noticeably louder than the other if the speakers were angled out towards the flats.

So, if you setup the amp in a bridged configuration with each pair of 4 ohm speakers wired in series (8 ohm load per pair) then wire the two pairs in parallel then the amp will "see" a 4 ohm load and put out much more power (i.e. louder) vs. the 4 channel, 16 ohm configuration.

If stereo isn't necessary, how do you propose to hear the signal from both channels, which have different content in a stereo mix, when you're skiing or 'boarding? Do you like to listen to only one channel? Speakers reproducing two channels of audio are effectively mono when they're very close together.

I didn't think so.

fentong
05-07-2011, 09:14 AM
This is a great thread, I wished you had started this back in January. I have a JL MHD600/4 and I just bought two more Bullet 7.7. HLCD cans from David at Earmark and I plan to use the MHD600/4 to drive each of the four speakers at 150 W RMS @ 4 Ohm each and still maintain stereo. I never considered the monoblock option. I haven't hooked it up yet so I can't comment on how it sounds.

Jeff d
05-07-2011, 09:18 AM
When you add a "load" ie another speaker the ohm value gets cut in half not added. so if running 4 speakers and each had 4 ohms than the new value will be .5 ohm if all speakers are used on 1 channel

Not totally true. If you add a load in series the impedance is added (i.e. 4+4+4+4=16). If you wired them all in parallel then you would get a 1 ohm load as you stated but there's no rule that says you can't mix parallel and series loads. So, you wire a pair of speakers (4 ohm each) in series and get an 8 ohm load for that pair. Do the same for the other pair and get another 8 ohm load. Wire those two 8 ohm loads up in parallel and you're back at a 4 ohm load which is perfect for most bridgeable 2 channel amps or a mono amp. This is exactly how I have mine setup right now and it works fine.

Jeff d
05-07-2011, 09:22 AM
If stereo isn't necessary, how do you propose to hear the signal from both channels, which have different content in a stereo mix, when you're skiing or 'boarding? Do you like to listen to only one channel? Speakers reproducing two channels of audio are effectively mono when they're very close together.

I didn't think so.

If you use a mono block amp (Like you'd typically use for a subwoofer) it combines the left and right channels automatically. If you use a bridgeable 2 channel amp you grab the + from one channel and the - from the other channel which will put the amp into mono mode. Either way all of the speakers will play the audio from both stereo channels.

Think about a subwoofer that's either on a mono amp, a bridged 2 channel amp or on the subwoofer channel of a 5/6 channel amp. It's not only playing the low frequencies from one channel, the amp is combining them.

JimN
05-07-2011, 10:57 AM
If you use a mono block amp (Like you'd typically use for a subwoofer) it combines the left and right channels automatically. If you use a bridgeable 2 channel amp you grab the + from one channel and the - from the other channel which will put the amp into mono mode. Either way all of the speakers will play the audio from both stereo channels.

Think about a subwoofer that's either on a mono amp, a bridged 2 channel amp or on the subwoofer channel of a 5/6 channel amp. It's not only playing the low frequencies from one channel, the amp is combining them.

I know what a mono block amp is but many only have one input. Also, there's more to bridging an amp that just using the L+ and R- speaker terminals. At the input, one channel needs to be inverted, which is why amplifiers have a switch for that function.

JimN
05-07-2011, 11:01 AM
Not totally true. If you add a load in series the impedance is added (i.e. 4+4+4+4=16). If you wired them all in parallel then you would get a 1 ohm load as you stated but there's no rule that says you can't mix parallel and series loads. So, you wire a pair of speakers (4 ohm each) in series and get an 8 ohm load for that pair. Do the same for the other pair and get another 8 ohm load. Wire those two 8 ohm loads up in parallel and you're back at a 4 ohm load which is perfect for most bridgeable 2 channel amps or a mono amp. This is exactly how I have mine setup right now and it works fine.

Series/parallel can be a problem for the crossover points. You can't place a complex crossover in series with another and get the intended results. If the woofers have a low pass filter, the series resistance and inductance of the coils and drivers will cause the F3 to change radically and the sound will never be what it should.

j.mccreight@hotmail.com
05-07-2011, 11:04 AM
Not totally true. If you add a load in series the impedance is added (i.e. 4+4+4+4=16). If you wired them all in parallel then you would get a 1 ohm load as you stated but there's no rule that says you can't mix parallel and series loads. So, you wire a pair of speakers (4 ohm each) in series and get an 8 ohm load for that pair. Do the same for the other pair and get another 8 ohm load. Wire those two 8 ohm loads up in parallel and you're back at a 4 ohm load which is perfect for most bridgeable 2 channel amps or a mono amp. This is exactly how I have mine setup right now and it works fine.

That configuration is not common in car or marine audio. This is a lot more common in musical instrument (guitar and bass guitar) speaker cabinets, being series and parallel, the only problem I have with that is you need to pay extra attention when hooking everything up and be prepared to do more math:rolleyes:

Jeff d
05-07-2011, 04:53 PM
Also, there's more to bridging an amp that just using the L+ and R- speaker terminals. At the input, one channel needs to be inverted, which is why amplifiers have a switch for that function.

At least in my particular case with an older HiFonics Zeus 2 channel (i.e. low end) that is all it takes. I went out and looked at my amp to make sure I wasn't crazy. No switch, just some labeling near the speaker terminals that indicates which + and - to use to bridge it.

I'm not that into car/boat audio anymore but I was to some extent in high school. I seem to recall most amps that I dealt with were similar to my Zeus amp when "bridging" them. I haven't dealt with any of the crazy expensive high end stuff that a lot of people have these days though.

I don't have any crossovers. Just 4 coaxial speakers in my tower cans and I'm using the high pass filter built into the amp. A really simple system by today's standards.

EarmarkMarine
05-07-2011, 06:04 PM
Brucemac,
As stated above a 3.7 ohm DC resistance or even a bit lower is very common on a 4-ohm nominal impedance speaker. That can be representative of the lowest point on the AC impedance curve but all speakers have a non-linear impedance. If that is what it measures with a basic multimeter then consider it a 4-ohm speaker with nothing to worry about.
Forrest,
The advantage of a fullrange monoblock in this case is that you get 25 percent more power for $100 less versus the same series 4-channel amplifier. Most Class D or other monoblocks are limited to lowpass operation. The JL Audio HD or MHD750/1 is the exception in that it is fullrange, highpass or lowpass with a true 20 to 20kHZ bandwidth. When using separate left and right inputs it mixes to mono so there is no missed program material. It has dual output terminals that parallel the speakers to the amplifier's outputs when both are used. There are endless wiring configurations to achieve a safe load for almost any speaker combination.
Stereo on the tower is a non-issue for me. There are several kinds of stereo. One is like an old Beatles album where you have distinct left and right material. That type of recording is rather rare. The second is that ideal scenerio where the speakers and listener form a symmetrical triangle so the psychoacoustical effect is intended to create a percieved bridge between the left and right speakers. The third would be an esoteric recording on an esoteric playback system where you could identify artist placement, a sense of depth and a sense of the original recording environment and its surroundings, but only when seated in the sweet spot. Anyone ever experienced any of these examples from any tower system? From HLCDs period? Didn't think so. There is no sweet spot. The tower speakers are as 'one' at the end of a rope. A horizontal array across a tower completely destroys any chance for a stereo image. The ambient noise masks any channel separation. In fact, installers of really big systems in cruisers usually run fullrange cockpit arrays on the same side of the boat that alternate left and right. True stereo imaging is dead just like home two-channel Hi-Fi. There are few enthusiusts left. Most have never even experienced it...certainly not from an ipod or from home theater which is a different effect. Bottom line: Don't sweat stereo. Sorry for killing the point. Its something that we've reflected on before now.

David
Earmark Marine

JimN
05-07-2011, 07:37 PM
At least in my particular case with an older HiFonics Zeus 2 channel (i.e. low end) that is all it takes. I went out and looked at my amp to make sure I wasn't crazy. No switch, just some labeling near the speaker terminals that indicates which + and - to use to bridge it.

I'm not that into car/boat audio anymore but I was to some extent in high school. I seem to recall most amps that I dealt with were similar to my Zeus amp when "bridging" them. I haven't dealt with any of the crazy expensive high end stuff that a lot of people have these days though.

I don't have any crossovers. Just 4 coaxial speakers in my tower cans and I'm using the high pass filter built into the amp. A really simple system by today's standards.

Is the Zeus about 3" x 4" x 8"? I think I have one around here, somewhere. I don't think I ever worked with any HiFonics stuff but if their amps don't need an inverted input signal, that makes them pretty unique.

JimN
05-07-2011, 07:44 PM
Brucemac,
As stated above a 3.7 ohm DC resistance or even a bit lower is very common on a 4-ohm nominal impedance speaker. That can be representative of the lowest point on the AC impedance curve but all speakers have a non-linear impedance. If that is what it measures with a basic multimeter then consider it a 4-ohm speaker with nothing to worry about.
Forrest,
The advantage of a fullrange monoblock in this case is that you get 25 percent more power for $100 less versus the same series 4-channel amplifier. Most Class D or other monoblocks are limited to lowpass operation. The JL Audio HD or MHD750/1 is the exception in that it is fullrange, highpass or lowpass with a true 20 to 20kHZ bandwidth. When using separate left and right inputs it mixes to mono so there is no missed program material. It has dual output terminals that parallel the speakers to the amplifier's outputs when both are used. There are endless wiring configurations to achieve a safe load for almost any speaker combination.
Stereo on the tower is a non-issue for me. There are several kinds of stereo. One is like an old Beatles album where you have distinct left and right material. That type of recording is rather rare. The second is that ideal scenerio where the speakers and listener form a symmetrical triangle so the psychoacoustical effect is intended to create a percieved bridge between the left and right speakers. The third would be an esoteric recording on an esoteric playback system where you could identify artist placement, a sense of depth and a sense of the original recording environment and its surroundings, but only when seated in the sweet spot. Anyone ever experienced any of these examples from any tower system? From HLCDs period? Didn't think so. There is no sweet spot. The tower speakers are as 'one' at the end of a rope. A horizontal array across a tower completely destroys any chance for a stereo image. The ambient noise masks any channel separation. In fact, installers of really big systems in cruisers usually run fullrange cockpit arrays on the same side of the boat that alternate left and right. True stereo imaging is dead just like home two-channel Hi-Fi. There are few enthusiusts left. Most have never even experienced it...certainly not from an ipod or from home theater which is a different effect. Bottom line: Don't sweat stereo. Sorry for killing the point. Its something that we've reflected on before now.

David
Earmark Marine

Stereo image isn't the point of using both channels to the tower but having only the right or left channel isn't what I would call 'acceptable'. It might be better to sum the channels before it gets to the amplifiers, either with a dedicated summing network or a Y cord.

BTW- two channel home HiFi is making a pretty strong comeback. A lot of people are deciding that surround, which isn't particularly realistic-sounding, it's worth worrying about as much as a full-range great sounding front presentation. High-end speakers and amp sales have increased a lot in the past couple of years. I think part of this is due to the iPod being a two channel device and in most cases, it sounds pretty dam bad with low bit-rate MP3 files. Once a lot of people hear a great sounding stereo system, they're either not using or not buying surround speakers.

Jeff d
05-07-2011, 10:01 PM
Is the Zeus about 3" x 4" x 8"?

Mine is a "200 watt" 2 channel bridgeable from circa '99-01. It's about 10"x12"x2" (width x height x thickness). It powers my 4 Polk DB651 tower speakers fine but I'm far from an Audiophile. I just want it to work, be sufficiently loud and not sound like crap.

It looks like this accept narrower because this is a 600 watt:
http://i17.photobucket.com/albums/b57/cellos88gt/PICT0227.jpg

EarmarkMarine
05-07-2011, 11:16 PM
JimN,
The JL Audio monoblock already sums the left and right signal in the input stage. I wouldn't sum the left and right with an external 'Y' adapter without having a buffer circuit.

I'm one of those trying to live a revival of two-channel home audio.

David
Earmark Marine

brucemac
05-08-2011, 01:31 PM
Brucemac,
As stated above a 3.7 ohm DC resistance or even a bit lower is very common on a 4-ohm nominal impedance speaker. That can be representative of the lowest point on the AC impedance curve but all speakers have a non-linear impedance. If that is what it measures with a basic multimeter then consider it a 4-ohm speaker with nothing to worry about.

David, chatted with Tim via email Friday and he thinks I should just swap the polk MM's down to channels 1-4 on the Syn6 at ~60W a piece and take care in tuning it. That would free up my Syn4 for a direct Pro80 swap to a pair of Rev 10's. I'm very interested in the advertised warmer, "less bright" characteristics of the new speakers and have to assume going from an 8in mid-bass driver to a 10in and twice the rated RMS per speaker is going to be a decent gain. I have a 420 as well.

Any thoughts on that recommendation? Have you heard the new Rev series yet?

Lastly, anybody have any guesses what I could get for a 2-year old pair of Pro 80's in great condition with TC2 clamps and boxes? $400 comes to mind, but not sure if that's reasonable or not.

TX.X-30 fan
05-08-2011, 02:54 PM
Don't like the pro 80's BM??

rebel92
05-09-2011, 08:14 AM
I will offer you $400 for your Pro 80 set with clamps. I don't have any tower speakers right now and am trying to accomplish what you are without spending as much money...just good sound. Thanks.

willyt
05-09-2011, 08:26 AM
You have had a PM waitin for ya Bruce...

Forrest-X45
05-09-2011, 01:54 PM
Forrest,
The advantage of a fullrange monoblock in this case is that you get 25 percent more power for $100 less versus the same series 4-channel amplifier. Most Class D or other monoblocks are limited to lowpass operation. The JL Audio HD or MHD750/1 is the exception in that it is fullrange, highpass or lowpass with a true 20 to 20kHZ bandwidth. When using separate left and right inputs it mixes to mono so there is no missed program material. It has dual output terminals that parallel the speakers to the amplifier's outputs when both are used. There are endless wiring configurations to achieve a safe load for almost any speaker combination.

David
Earmark Marine

Thanks David and everyone else for your extremely helpful advice. This is exactly the type of help I was looking for.
It sounds like the MHD 750/1 is the best bang for buck to power the JL tower speakers.

David - would you be willing to provide a good starting point to wiring up the JL MHD 750/1 to the JL tower speakers? You mentioned endless wiring configurations so could you recommend a good one? Would you recommend a professional install and configure the amp? Thanks for all your helpful advice!

mseller
05-09-2011, 02:14 PM
basically you are going to want a 4ohm total load when you are finished wiring. To accomplish this, wire speaker 1 in series with speaker 2 which will give you 1 pair. Then, wire speaker 3 in series with speaker 4 which will give you the 2nd pair. Finally wire pair 1 in parallel with pair two and you will have a 4 ohm load.

brucemac
05-09-2011, 03:22 PM
I will offer you $400 for your Pro 80 set with clamps. I don't have any tower speakers right now and am trying to accomplish what you are without spending as much money...just good sound. Thanks.

You have had a PM waitin for ya Bruce...

rebel92, willyt actually had pm'd me first over the weekend and i have to respect that and give him first dibs. i'll keep your pm and you're 2nd on the list.

i'm waiting for the rev 10's to come out at the end of may, so it could be a few more weeks. i'd also really like to hear them before i pull the trigger.

agarabaghi
05-09-2011, 03:28 PM
485 Pro! 485 Pro!