John Sayers' Design Forum

John Sayers' Recording Studio Design Forum

A World of Experience
Click Here for Information on John's Services
It is currently Fri Dec 13, 2019 7:32 am

All times are UTC + 10 hours




Post new topic Reply to topic  [ 275 posts ]  Go to page Previous  1 ... 8, 9, 10, 11, 12, 13, 14 ... 19  Next
Author Message
PostPosted: Sun Dec 13, 2009 4:37 am 
Offline
User avatar

Joined: Thu Aug 28, 2008 7:33 am
Posts: 289
Location: Eliot, Maine
Hey everyone quick question here, while I'm waiting for my loan to be approved (fingers crossed) I've been shopping HVAC Ideas. One of the quotes I received was quite a high price for 700 sf, so I decided to explore my other options at the moment. I am somewhat leaning towards using mini splits now - http://www.gt-world.com/split_air_conditioner_9000_btu_silver_panel. My question, or more my assumption is that I still need an air exchange/return coupled with these units, correct? Given that, is it common to AC/Heat the vocal booth, or would it be more efficient to just add the air exchange/return in there, since my vocal booth is quite small, any ideas????

_________________
Gvgeyuhi Edudi, Nulinega!! Hoka Hey!!!


Report this post
Top
 Profile  
 
PostPosted: Thu Dec 17, 2009 5:08 am 
Offline
User avatar

Joined: Thu Aug 28, 2008 7:33 am
Posts: 289
Location: Eliot, Maine
So the first phase of electric has been run, next will be the lights, then the air units. I also removed the windows, framed and sealed them up. :) I'm deciding to go with an cheaper route for the HVAC system and I am looking into running 2 12k btu units for the CR and LR, and 1 9k btu unit for the drum booth, of these mini splits - http://www.gt-world.com/split_air_conditioner_9000_btu_silver_panel For my air exchange & return I was thinking of purchasing a Fantech ventilator - http://www.iaqsource.com/product.php?p=fantech_se-704n&product=113523&category=946 I will install what I can and then hire a tech pro to finish the rest. That's my idea at the moment, if anyone has any comments please, I would love to hear. I'm really looking forward to getting this part done, because then I can finally start insulating, and throwing up sheetrock!!! :D Other than my photos, I've also included an drawing for my silencer return/exchange, it is not to scale mind you, but any feedback on that (especially if I'm doing it wrong) would be much appreciated. All duct work will be run on the crawlspace surface (not in between leafs)

Hope everyone is staying warm


You do not have the required permissions to view the files attached to this post.

_________________
Gvgeyuhi Edudi, Nulinega!! Hoka Hey!!!


Report this post
Top
 Profile  
 
PostPosted: Thu Dec 17, 2009 6:11 am 
Offline
User avatar

Joined: Wed Dec 06, 2006 6:22 pm
Posts: 144
Location: Berlin, Germany
hey native,

don't know if the sketch of your silencer is to scale but what i see is that you'll have three dimension/velocity changes in your drawing.
meaning every turn in your silencer will increase velocity then slows down again, increases again, slows down and same again. this will cause
noise (air noise).
what i have read is:
increasing only the opening diameter of your inlet/outlet is what you want.
this will slow down the velocity at a point of interest (to reduce potentially air noise in your room)
see my quickly pimped sketch of yours...
Attachment:
AutoSave_Untitled copy.jpg


hope this helps (and is correct)

another point:
can you please post the link to where you show or describe your exchange chamber/fresh air exchange details?
thanks.

carsten


You do not have the required permissions to view the files attached to this post.


Report this post
Top
 Profile  
 
PostPosted: Thu Dec 17, 2009 10:40 am 
Offline
User avatar

Joined: Thu Aug 28, 2008 7:33 am
Posts: 289
Location: Eliot, Maine
Thanks for the quick reply Carsten,

If I understand you correctly, the opening at the last point in the silencer should be twice the diameter of the ducting that I am using, as well as the ducting itself. So if I'm using 4" ductwork, the opening and ductwork to the register should be 8"? Or do you mean only at the register should the opening be twice in size? I revised the sketch how I thought you were speaking of, please let me know if I'm still not getting it :oops: I have also included a diagram of my ventilation exchange.


You do not have the required permissions to view the files attached to this post.

_________________
Gvgeyuhi Edudi, Nulinega!! Hoka Hey!!!


Report this post
Top
 Profile  
 
PostPosted: Thu Dec 17, 2009 8:52 pm 
Offline
User avatar

Joined: Wed Dec 06, 2006 6:22 pm
Posts: 144
Location: Berlin, Germany
native, you're welcome.

look in my thread -> click click
scroll a little down to SECOND and read from there to the end of the post.
there are many points of interest for you.

in your example it should be more like this:
Attachment:
AutoSave_Untitled copy2.jpg


where x is your diameter and should all over be the same (the turns in your silencer, too!) except at
the register/opening
.
the more baffles in your silencer the better (like in your 1st design or the one above).
if you read through the text in my thread you'll find an explanation why one should avoid abrupt changes in
duct cross-sectional area e.g. (that's why the register is like a cone)

ventilation exchange.
you'll have the ventilator in your live room? i guess it's in the crawl space above, isn't it.
remember that the 'fresh air in' and 'stale air out' should be far away from each other! otherwise
you'll suck the stale air in again.

looks like you'll have 3 mini split systems (drum booth, live room and control room).
wouldn't it be cheaper to use an exchange chamber with only 1 split system and of course the
ventilator for fresh air?
also i'm not sure if the fantech recovery ventilator is strong enough...

maybe you'll check my link for that, too.

greetings,
carsten


You do not have the required permissions to view the files attached to this post.


Report this post
Top
 Profile  
 
PostPosted: Fri Dec 18, 2009 5:15 am 
Offline

Joined: Sat Jan 07, 2006 6:22 pm
Posts: 102
Location: Saint Louiee
It seems to me that you will have to extend your inner leaf up to (but not touch?) the silencers. Otherwise you will destroy your isolation. Ideally the silencer and ductwork would exist in between your inner and outer leafs and the box would just be an extension of the room.

Carsten, do you mean that the radius of the opening should be 2X, or the area of the opening should be 2X?


Report this post
Top
 Profile  
 
PostPosted: Fri Dec 18, 2009 5:22 am 
Offline
User avatar

Joined: Wed Dec 06, 2006 6:22 pm
Posts: 144
Location: Berlin, Germany
stuntbutt,

yeah, i should have been a bit more precise about that.
as far as i've understood it by reading it should be the (cross sectional) area.
there is a difference between simply double a diameter or an area...

c.


Report this post
Top
 Profile  
 
PostPosted: Fri Dec 18, 2009 8:33 am 
Offline
User avatar

Joined: Thu Aug 28, 2008 7:33 am
Posts: 289
Location: Eliot, Maine
Stuntbutt - I'm a little confused on what you mean by extending my 1st leaf upward? I was planning on using flex duct between both leafs after the silencer as to prevent any decrease in isolation.

carsten_d - After reading your thread, lets see if I got this right now, The ductwork diameter should be the same everywhere - matching the diameter of the silencer, UNTIL it comes to the entrance of the register, correct?

As for the ventilator, I forgot to mention all ductwork along with the HRV will be surface mounted on the floor of the crawlspace/attic, I forgot to distance the return and exhaust apart in my drawing, but they will be by roughly 8 feet. As for the ventilator itself after doing my math for my space, I'm looking at a Fantech SHR 1504 - http://www.shophmac.com/fantech-shr-1504.html I don't have my calculations in front of me, but my minimum airflow required came out to about 35 cfm with 5740 cubic volume, so I'm thinking the 1504 should be able to fufill my needs, but will give them a call to double check regardless.

As for using an exchange chamber, I would rather keep a clean install above my head, and with the splits, each being roughly $600 and as well as the HRV, I'm looking at under 2500 for the gear, and some extra for a pro to do the final touches. It would also be nice to keep each room to its own individual zone.

Thanks again for your help Carsten, lemme know if something is still not sinking in - this whole HVAC stuff is not my strong-point of course :oops:

_________________
Gvgeyuhi Edudi, Nulinega!! Hoka Hey!!!


Report this post
Top
 Profile  
 
PostPosted: Fri Dec 18, 2009 5:43 pm 
Offline
Senior Member
User avatar

Joined: Sat Mar 29, 2003 12:26 am
Posts: 2073
Location: Netherlands
carsten, thanx for the links to those other treats. MUST-READ stuff :)


Report this post
Top
 Profile  
 
PostPosted: Fri Dec 18, 2009 6:01 pm 
Offline
User avatar

Joined: Wed Dec 06, 2006 6:22 pm
Posts: 144
Location: Berlin, Germany
hola native =)

yes. if the whole system is made of round ducts and silencers...
otherwise, as stuntbutt already mentioned:
the cross sectional area should be the same.
e.g.:
cross sectional area of a 4" flex duct -> pi*r²=3,141*2²= 12,56 inch²
cross sectional area for the silencer (i guess it will be square) should be 12,56 inch²
now the calculation for the dimensions is easy: 12,56 inch²/ 4" = 3,14"
you'd need all the way through your silencer at each point in the silencer at least an opening
of 4" x 3,14" to meet the same cross sectional area as in the 4" flex duct.

yes. UNTIL the register.
and keep in mind to avoid abrupt changes.


to be honest:
every little bit in studio construction seems to be my weak-point.
every day i learn a little more. every day i learn that i'm still at the beginning...that said...
erm...cough...cough...

i followed these guides in my build and am absolutely satisfied how good it all worked out.
i feel a breeze but hear nothing. my window panes and superduperdoors are def more worse than my
silencer system.

but i still don't know if my system is balanced. or, what about the static pressure? or,...

questions. questions. questions...

good luck,
carsten


Report this post
Top
 Profile  
 
PostPosted: Fri Dec 18, 2009 8:54 pm 
Offline
User avatar

Joined: Wed Dec 06, 2006 6:22 pm
Posts: 144
Location: Berlin, Germany
oh. ro.
:)
i haven't seen your post.
i guess it was too early in the morning...half asleep
:inn:
thank you.


Report this post
Top
 Profile  
 
PostPosted: Sat Dec 19, 2009 2:13 pm 
Offline

Joined: Sat Jan 07, 2006 6:22 pm
Posts: 102
Location: Saint Louiee
NativeLuv17 wrote:
Stuntbutt - I'm a little confused on what you mean by extending my 1st leaf upward? I was planning on using flex duct between both leafs after the silencer as to prevent any decrease in isolation.


You are cutting holes in your inner leaf ceiling in every room. Sound will travel out of one hole, pass through the flex duct, travel in the space between inner and outer leafs, through the flex duct and into the next room.


Report this post
Top
 Profile  
 
PostPosted: Mon Dec 21, 2009 10:24 am 
Offline
User avatar

Joined: Thu Aug 28, 2008 7:33 am
Posts: 289
Location: Eliot, Maine
So the HRV I'm looking at getting uses 6" ducts, if pi*r², that means I'm looking at an opening/register 28.3" :shock: ???? Is that the width for the opening, or am I missing something here, that's enormous!!! (that's what she said: saved you the trouble hahah)

Also if 60 - 75 cfm's is standard for a 1 person with max consumption of fresh air, do I determine the amount of cmf's for my air exchange by multiplying the maximum amount of people occupying my studio by the cfm standard???

Meanwhile I redrew my silencer idea, and added an insulated custom coned opening I would make out of osb or mdf


You do not have the required permissions to view the files attached to this post.

_________________
Gvgeyuhi Edudi, Nulinega!! Hoka Hey!!!


Report this post
Top
 Profile  
 
PostPosted: Wed Dec 23, 2009 7:35 am 
Offline
User avatar

Joined: Thu Aug 28, 2008 7:33 am
Posts: 289
Location: Eliot, Maine
Hey everyone, I'm planning on ordering my mini splits tomorrow, as well as an air exchange (HRV). I was wondering if anyone has any tips or things I should know before I make my final purchase???

Gracias N8V

_________________
Gvgeyuhi Edudi, Nulinega!! Hoka Hey!!!


Report this post
Top
 Profile  
 
PostPosted: Wed Dec 23, 2009 7:55 am 
Offline
User avatar

Joined: Wed Dec 06, 2006 6:22 pm
Posts: 144
Location: Berlin, Germany
sorry...
i missed your last post.
pi*r² is the cross-sectional area of your duct. so you'll have a cross-sectional area of 28,3 inch².
your opening (aka register) should at least have a cross-sectional area twice that size:
meaning: 56,6inch²!
this is NOT the width...it's the area!
don't know if you want to purchase a "real" register (better flow/spread, lower noise) but it should fit
that size...meaning 8"x7" or 10"x5,66" or whatever ... (I don't know the available sizes, sorry)

to your 2nd question:
that's why i asked a few posts ago...

i'll get back to you...hang on for a sec.

greetz,
carsten


Report this post
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 275 posts ]  Go to page Previous  1 ... 8, 9, 10, 11, 12, 13, 14 ... 19  Next

All times are UTC + 10 hours


Who is online

Users browsing this forum: Gregwor and 16 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group