grafxdesin
Super Member
Hmmm, ok. Being a vintage guy I am going to start looking for a 100w amp that can hopefully drive the GW-410D's (4 of them).
Open Baffle Epiphany!
- Thread starter cptnCanada
- Start date
Hmmm, ok. Being a vintage guy I am going to start looking for a 100w amp that can hopefully drive the GW-410D's (4 of them).
cubdog
banging through drywall
I'd look for something by Parasound, Rotel, or Adcom. A sleeper and the most affordable might be an Audiosource amp. Don't get hung up on vintage for the sake of vintage. Why? You want value and performance what the hell difference does the year make? Besides the older a piece of gear the more likely it will need work sooner than later. Also, an amp is an amp whatever vintage it is. It won't, in most cases, look much different be it from the 70s, 80s, 90s, or whenever.
cubdog
grafxdesin
Super Member
I know, but I do like the look of the vintage gear and all of my stuff is vintage so it will fit in.
grafxdesin
Super Member
Opinions please, about to place my order for my woofers, FR will be Betsy's (just ordered) and now I am trying to decide between one pair of Eminence Alpha 15a's or 2 pairs of the Goldwood GW-410d 10". Both have great reviews.
noise gate
Super Member
OK, It's -39 tonight with a -50 something wind chill and I'm really fascinated with the Open Baffle world. I ain't leaving the yard, bored as hell and have some plywood and a pair of 6x9 car speakers in the garage. Oh, and some piano hinge too.
If I slapped something together would that get me into the OB club, or would I be shunned as a heretic for using automotive speakers?
If I slapped something together would that get me into the OB club, or would I be shunned as a heretic for using automotive speakers?
I don't think you'll find anybody around here that's worked with the GW's but me. They're an econo sleeper. A number of folks should be able to comment on the Alpha's.
Looking at spec's. The resonant freq of the GW is a nice number lower. The inductance is lower. Sensativity similar. Power handling rating is higher on the Alpha's with a little more xmax. Cone area for the two would be a similar to the single 15. And the price would be about $85 for the four versus $130 for the pair of Eminence. To me, the number difference that jumps out is the total Q. The GW's, a touch below ideal for OB. The Alpha's past ideal.
Oh, and the GW's have dual 4 ohm coils. So you can present an amp with a 4 ohm or 16 (I suggest not having four in series).
To me, the GW's really do a nice job for less money, if that's important. I'd rather think I could eq a little more bottom if I wanted to, which I've never felt compelled to. I can't tame an overly resonant design. As a set of four GW's for less than $200 delivered, I don't think their tunefullness and impact can be questioned. They shock me sometimes on the low notes I hear mounted on only about 20 inches.
EV3
Looking at spec's. The resonant freq of the GW is a nice number lower. The inductance is lower. Sensativity similar. Power handling rating is higher on the Alpha's with a little more xmax. Cone area for the two would be a similar to the single 15. And the price would be about $85 for the four versus $130 for the pair of Eminence. To me, the number difference that jumps out is the total Q. The GW's, a touch below ideal for OB. The Alpha's past ideal.
Oh, and the GW's have dual 4 ohm coils. So you can present an amp with a 4 ohm or 16 (I suggest not having four in series).
To me, the GW's really do a nice job for less money, if that's important. I'd rather think I could eq a little more bottom if I wanted to, which I've never felt compelled to. I can't tame an overly resonant design. As a set of four GW's for less than $200 delivered, I don't think their tunefullness and impact can be questioned. They shock me sometimes on the low notes I hear mounted on only about 20 inches.
EV3
grafxdesin
Super Member
, I do as well, just trying to get as much info as possible, I have learned so much already and I thank all of you, this would be impossible with out all this info!Cheers
I believe with those kind of temps, you'll be forgiven!
EV3
No matter the temp, go for it. More than one thread on other forums with guys using car speakers for OB, some with very good results.
AK member Poultrygeist wisely suggested the use of auto speakers for OB use back on page 31. He also mentioned cheap auto salvage yard Delco 6 x 9s. So, I looked around and found some new 8 ohm Delco 6 x 9s for under $25 a pair shipped. Should have them by next week...
Poultrygeist
Lunatic Member
There's an excellent thread on Audio Circle ( OB Circle ) regarding the DIY Hestia OB's that's worth reading. In that build 10" MCM woofers are used first as mids and then as H-frame woofers ( aka H-bombs ). Best part is these woofers are only $29 each and have very high build quality. I've mentioned them before but here's the link in case anyone's interested.
http://www.mcmelectronics.com/produ...ium=Affiliate&utm_campaign=CommissionJunction
http://www.mcmelectronics.com/produ...ium=Affiliate&utm_campaign=CommissionJunction
dnewma04
The Healer
Many car speakers use high Q designs because of the leaky environments they reside in. Keep in mind that the drivers that work well are the ones designed to be installed in doors and package trays, not subwoofer type drivers.
cubdog
banging through drywall
Well some of your gear is vintage. I believe your speakers will qualify as new. :yes:
cubdog
grafxdesin
Super Member
Thank you EV3, I will be going with the 4 GW-410D for my set-up!
Poultrygeist
Lunatic Member
If the GW's are 4 ohms and you run pairs in parallel that would present a problem for many amps.
Each GW 410 is dual 4 ohm coils. Yes, using four drivers, you must pay attention to load. If you series each driver, then when you parallel the four, it would in theory roughly present a 2 ohm load. Too much!
An alternate might be to use a stereo amp on each side, using each channel to run a pair of drivers, again series the coils and then parallel the drivers for a 4 ohm load. Before you start...have a plan.
Some comments....
- I found sonics compromised when you series too many of any of the drivers.
- I've measured most stacked parallel drivers to wind up showing less load than predicted...a little.
- The efficiency helps with power needs. You wind up with very, very nice impact on the lows with the multiple drivers and a lot of cone area.
- I've run the GW mostly rolled in below full range driver stack at about 75-80hz. But have run them short term below a single FR driver up to about 250 or so and didn't feel like it was a problem sonically. The higher you go, the more placement will become an issue.
- I think my four stack is about 48" so having a full range above those is really too high.
EV3
An alternate might be to use a stereo amp on each side, using each channel to run a pair of drivers, again series the coils and then parallel the drivers for a 4 ohm load. Before you start...have a plan.
Some comments....
- I found sonics compromised when you series too many of any of the drivers.
- I've measured most stacked parallel drivers to wind up showing less load than predicted...a little.
- The efficiency helps with power needs. You wind up with very, very nice impact on the lows with the multiple drivers and a lot of cone area.
- I've run the GW mostly rolled in below full range driver stack at about 75-80hz. But have run them short term below a single FR driver up to about 250 or so and didn't feel like it was a problem sonically. The higher you go, the more placement will become an issue.
- I think my four stack is about 48" so having a full range above those is really too high.
EV3