AutoTuba Plan Question

[Fresh101]

Hello Everyone, I am new here and have gotten the plan on the autotuba. I believe I will be making the TAT instead of the original plan. Its recommended 4 different sub for the original plan, and I am not sure what to use. After reading the plan and steps, I have a few questions:

1-Three of the recommended subs are 8" and one is 10", which one is recommended for this project for maximum output?
MCM 55-2421, DCS 205-4, W8-740 and the 10" DCS 255-4.

2- Is the plan design measurements for the 8" or the 10"? The answer to this question also apply to the TAT layout?

3- NOTE: This is just questions, for knowledge. If for the 1st question is recommended to use 10" and the 2nd question was answered that the plan was for 8", then how do I know what size the boards needs to be cut? I need maximum output, it doesn't matter if I need to go wider 12 to 17 inches if 8" and 14 to 19 inches if 10".

***I am interested on the TAT layout instead of the original plan.

4- Based on the 3rd question. If it's 10" sub recommended, do I need to make the overall width 19" for maximum output or anything around 14" to 19"?

Thanks in advance

[Michael Ewald Hansen]

Hello Everyone, I am new here and have gotten the plan on the autotuba. I believe I will be making the TAT instead of the original plan. Its recommended 4 different sub for the original plan, and I am not sure what to use. After reading the plan and steps, I have a few questions:

1-Three of the recommended subs are 8" and one is 10", which one is recommended for this project for maximum output?
MCM 55-2421, DCS 205-4, W8-740 and the 10" DCS 255-4.

2- Is the plan design measurements for the 8" or the 10"? The answer to this question also apply to the TAT layout?

3- NOTE: This is just questions, for knowledge. If for the 1st question is recommended to use 10" and the 2nd question was answered that the plan was for 8", then how do I know what size the boards needs to be cut? I need maximum output, it doesn't matter if I need to go wider 12 to 17 inches if 8" and 14 to 19 inches if 10".

***I am interested on the TAT layout instead of the original plan.

4- Based on the 3rd question. If it's 10" sub recommended, do I need to make the overall width 19" for maximum output or anything around 14" to 19"?

Thanks in advance

1. 10" for highest single woofer output. You could build it with a dual 8" for even more output.

2. Plan is for both sizes, everything except the holes in the baffle is unchanged no matter which size woofer you pick.

3. The wider you go, the more sensitivity you get - within the max width defined in the plans

4. If you don't care about size, go 19" for max output with a single 10".

[Fresh101]

1. 10" for highest single woofer output. You could build it with a dual 8" for even more output.

2. Plan is for both sizes, everything except the holes in the baffle is unchanged no matter which size woofer you pick.

3. The wider you go, the more sensitivity you get - within the max width defined in the plans

4. If you don't care about size, go 19" for max output with a single 10".

Thanks for the quick response.

In question #1, you suggested dual 8" for higher output, but did not mentioned which one is better than the other 2, also in question #4, you suggested single 10" for maximum output. Clarify to which one will be great, a dual 8" or a single 10" with wider box?

For question #2, does more sensitivity means louder/higher output?

Is there any new/better 8" or 10" sub for this built that has been tested after the plan was updated? Thanks again and sorry for all the questions.

[Michael Ewald Hansen]

1. 10" for highest single woofer output. You could build it with a dual 8" for even more output.

2. Plan is for both sizes, everything except the holes in the baffle is unchanged no matter which size woofer you pick.

3. The wider you go, the more sensitivity you get - within the max width defined in the plans

4. If you don't care about size, go 19" for max output with a single 10".

Thanks for the quick response.

In question #1, you suggested dual 8" for higher output, but did not mentioned which one is better than the other 2, also in question #4, you suggested single 10" for maximum output. Clarify to which one will be great, a dual 8" or a single 10" with wider box?

For question #2, does more sensitivity means louder/higher output?

Is there any new/better 8" or 10" sub for this built that has been tested after the plan was updated? Thanks again and sorry for all the questions.

Dual 8" is very likely to have higher output than a single 10" depending on the drivers used. Where in the world are you from? There is different driver availability depending on your location.

Sensitivity = SPL, is the amount of sound pressure a speaker can output with 1watt of input measured from a 1meter distance. Higher SPL = more output.

All the drivers in the plan work as intended. One driver not mentioned is the JBL GTO804 which works absolutely fine aswell - I use one in AT's and it works great.

[Fresh101]

1. 10" for highest single woofer output. You could build it with a dual 8" for even more output.

2. Plan is for both sizes, everything except the holes in the baffle is unchanged no matter which size woofer you pick.

3. The wider you go, the more sensitivity you get - within the max width defined in the plans

4. If you don't care about size, go 19" for max output with a single 10".

Thanks for the quick response.

In question #1, you suggested dual 8" for higher output, but did not mentioned which one is better than the other 2, also in question #4, you suggested single 10" for maximum output. Clarify to which one will be great, a dual 8" or a single 10" with wider box?

For question #2, does more sensitivity means louder/higher output?

Is there any new/better 8" or 10" sub for this built that has been tested after the plan was updated? Thanks again and sorry for all the questions.

Dual 8" is very likely to have higher output than a single 10" depending on the drivers used. Where in the world are you from? There is different driver availability depending on your location.

Sensitivity = SPL, is the amount of sound pressure a speaker can output with 1watt of input measured from a 1meter distance. Higher SPL = more output.

All the drivers in the plan work as intended. One driver not mentioned is the JBL GTO804 which works absolutely fine aswell - I use one in AT's and it works great.

I did not asked if they are many other subs, I asked based on the plan, which one was better for the use, as the price range are different as well?

[Michael Ewald Hansen]

I did not asked if they are many other subs, I asked based on the plan, which one was better for the use, as the price range are different as well?

The 3 mentioned 8" drivers have approximately the same output.

I asked you where you are from because some drivers are easier to come by than others in different parts of the world.

[Fresh101]

I did not asked if they are many other subs, I asked based on the plan, which one was better for the use, as the price range are different as well?

The 3 mentioned 8" drivers have approximately the same output.

I asked you where you are from because some drivers are easier to come by than others in different parts of the world.

I live in the USA Miami FL

[Michael Ewald Hansen]

I did not asked if they are many other subs, I asked based on the plan, which one was better for the use, as the price range are different as well?

The 3 mentioned 8" drivers have approximately the same output.

I asked you where you are from because some drivers are easier to come by than others in different parts of the world.

I live in the USA Miami FL

Then i'd recommend the MCM 55-2421 for the most bang for the buck - at 37$ its really hard to beat

Build it wide with 2 drivers if you really want a lot of output..

[Ryan A]

For maximum output I'd recommend a Dual JBL GTO 804 setup...$20 more than the MCM for a better built driver that has more power and displacement.

You can get them direct from JBL off ebay for $56 shipped (USA)

You're correct, its not a recommended driver but many people have used it with great success, including me.

If you still want to go "recommended drivers" use the dayton 10.

Built it as wide as you can for the space that you will be using it, up to the maximum width specified in the plans for a dual configuration.

Don't worry too much about SPL specs on the drivers. Focus on Xmax and RMS power rating of the recommended drivers to determine output.

[Fresh101]

For maximum output I'd recommend a Dual JBL GTO 804 setup...$20 more than the MCM for a better built driver that has more power and displacement.

You can get them direct from JBL off ebay for $56 shipped (USA)

You're correct, its not a recommended driver but many people have used it with great success, including me.

If you still want to go "recommended drivers" use the dayton 10.

Built it as wide as you can for the space that you will be using it, up to the maximum width specified in the plans for a dual configuration.

Don't worry too much about SPL specs on the drivers. Focus on Xmax and RMS power rating of the recommended drivers to determine output.

Well based on the recommendation of going dual 8" for maximum output, how do I go about the built when it comes to the width 19-34" (lets say I go with 30"), cutouts of the panels from the plan (size increased by what), braces (size increased by what)? Any illustration on a dual built? Thanks again for the help.

[Michael Ewald Hansen]

For maximum output I'd recommend a Dual JBL GTO 804 setup...$20 more than the MCM for a better built driver that has more power and displacement.

You can get them direct from JBL off ebay for $56 shipped (USA)

You're correct, its not a recommended driver but many people have used it with great success, including me.

If you still want to go "recommended drivers" use the dayton 10.

Built it as wide as you can for the space that you will be using it, up to the maximum width specified in the plans for a dual configuration.

Don't worry too much about SPL specs on the drivers. Focus on Xmax and RMS power rating of the recommended drivers to determine output.

Well based on the recommendation of going dual 8" for maximum output, how do I go about the built when it comes to the width 19-34" (lets say I go with 30"), cutouts of the panels from the plan (size increased by what), braces (size increased by what)? Any illustration on a dual built? Thanks again for the help.

You just increase the width of all the panels to 30".

You put in braces for every 8 inches of width, so for a 30" externally wide cab with 29" internals, i'd use 2 braces per panel

[Fresh101]

You just increase the width of all the panels to 30".

You put in braces for every 8 inches of width, so for a 30" externally wide cab with 29" internals, i'd use 2 braces per panel

Ok, got you on the first part but on the second part you mentioned, "put a brace every 8" of width, so for a 30" you said to use 2 brace per panel. Based on the 8" rule, it should be approx. 3 braces, the last brace been at 24" (8", 16", 24")?

[Michael Ewald Hansen]

You just increase the width of all the panels to 30".

You put in braces for every 8 inches of width, so for a 30" externally wide cab with 29" internals, i'd use 2 braces per panel

Ok, got you on the first part but on the second part you mentioned, "put a brace every 8" of width, so for a 30" you said to use 2 brace per panel. Based on the 8" rule, it should be approx. 3 braces, the last brace been at 24" (8", 16", 24")?

Sure, you can put in 3 braces - its fine.. a 30" wide cab will have 29" internal width, so its borderline. Im pretty sure 2 braces will be enough

[Fresh101]

Thanks for all the response guys.

I am in the process of purchasing the dual 8" but wondering how will I wire the 2 speakers to get the most out of the amp?

I am using an amp that push 300 RMS Watts @ 4 or 8 Ohms. The JBL 8" sub that was recommended is a single 4 Ohms, if using two of them, I will need to wire the speakers in series making it a 8 Ohms load. Will this decrease the speaker/tuba overall output?

[SirNickity]

If it's 300W either way, probably not. Depends on the amp. Typically, power output at 4 ohms is higher than at 8 ohms because the amp is delivering more current at the same voltage.

If your choices are 4 or 8 ohms total, and you're using a 4 ohm driver, it looks like series wiring is your only option. Unless you have a stereo amp. Then you can run parallel inputs, one channel per driver.