Older 5.1 Receiver as Amp

[KEW]

I thought plugging the port would decrease output, while actually increasing extension, no? Turning it into a sealed sub should let it reach a bit deeper, but decrease maximum output I thought?

I did say it would decrease low frequency output. I guess the question is which range of frequencies are we addressing.
Uh, well, this gets confusing. If you are looking at +/- 2db, the ported has more extension. If you are looking at +/- 6db, the sealed has greater extension. However, since the good Dr. Hsu calls sealed configuration the "maximum extension" configuration, I guess I am using the wrong convention.
Thanks for helping me learn this!
To avoid confusion, I would now say "Plugging the port will cause the sub to roll-off sooner, which may reduce resonance in your room".


From the Hsu website, here is the VTF-15H sub with both ports open

Here is the VTF-15H sub sealed

 

[fuzz092888]

Well its not exactly the same since HSU (and outlaw) both have that switch on the back to change from max output mode to bass extension mode. The variable tuning feature is what helps keep everything flat and even when you plug a port.

When you plug a port on a single tuned sub, I'm not exactly sure what it'll do or if it will be bad for the driver.

 

[KEW]

Well its not exactly the same since HSU (and outlaw) both have that switch on the back to change from max output mode to bass extension mode. The variable tuning feature is what helps keep everything flat and even when you plug a port.

When you plug a port on a single tuned sub, I'm not exactly sure what it'll do or if it will be bad for the driver.

Note that Hsu recommends using the sub sealed in either EQ1 or EQ2 mode.

All I can say is people have been plugging ports for many, many years. I've never heard of a problem.

 

[ahblaza]

Well its not exactly the same since HSU (and outlaw) both have that switch on the back to change from max output mode to bass extension mode. The variable tuning feature is what helps keep everything flat and even when you plug a port.

When you plug a port on a single tuned sub, I'm not exactly sure what it'll do or if it will be bad for the driver.

I was under the impression a sub was designed to be ported or sealed, not both, sealing a vented sub with a plug has to be a compromise I would expect as far as output is concerned, might get a few Hz's extension at the expense of output, maybe I'm crazy to, I don't think having the option to make a sub sealed with a plug is a good thing, maybe Kurt is right, people have been doing so for years, to what end though, seriously.

 

[Bryceo]

My turn my turn Yamaha AVRS have the A great power output to run most large speakers you will not need a secondary amp...
as others have pointed out go in to your settings on the avr and set them correctly

 

[Budabear]

While you probably don't really want to spend the extra cash on a receiver you do possibly have a choice you didn't think about. You have your JVC collecting dust, that actually gives you two receivers you can sell to get cash towards another better receiver.

It would be good to upgrade your sub also but that could wait until your ready. With a sub in your system you should set your front speakers as small. If you have it set to large then your receiver doesn't send much of a signal to your sub. With the front speakers set to small your receiver is looking for the sub for better enhancement.

You never know, with a good receiver and auddessy you might end up with bass you can enjoy.

 

[Grador]

Why was this 3 month old thread resurrected?

 

[lsiberian]

I was under the impression a sub was designed to be ported or sealed, not both, sealing a vented sub with a plug has to be a compromise I would expect as far as output is concerned, might get a few Hz's extension at the expense of output, maybe I'm crazy to, I don't think having the option to make a sub sealed with a plug is a good thing, maybe Kurt is right, people have been doing so for years, to what end though, seriously.

It really depends on the design and driver. Some people love a lowly tuned sealed sub because it's excellent for sub-20hz performance. The ultimate example of this is in the IB.

 

[fuzz092888]

I was under the impression a sub was designed to be ported or sealed, not both, sealing a vented sub with a plug has to be a compromise I would expect as far as output is concerned, might get a few Hz's extension at the expense of output, maybe I'm crazy to, I don't think having the option to make a sub sealed with a plug is a good thing, maybe Kurt is right, people have been doing so for years, to what end though, seriously.

The difference between plugging a vented sub and plugging a variable tuned sub is that switch on the amp. I'm not sure what magic it does, but it obviously does something that simply plugging the port on say one of those kappas that we see being built every so often would do. Yes you are definitely correct about output and that's the whole point about the variable tuning. If you are using the sub in an application where max output is favored, then you leave the ports wide open. If you are getting more than enough bass for your application you can plug both ports and get a bit more low frequency extension and if you are somewhere in the middle then maybe plugging one port will fit the bill. IMHO the point of all these shenanigans is so that if you are unsure whether a sealed or a vented sub will be best for your specific room and tastes, it allows to try both and pick which you like the best.

 

[ahblaza]

Thanks Alex for the explanation, I guess the less shenanigans the better for me. Less complications equals less room for error, that's just me though, I think I have a handle on what I think is best for my room, I've had both ported and sealed and decided sealed is the way to go for me, my room and my tastes. Thanks Brother.
Cheers, Jeff