|
|
Joined:
August 2012
Posts: 17
Location: Auckland, New Zealand | DanSavage - 2012-11-02 9:59 AM
While the bowls are made in the US, their materials and method of manufacture has changed over the years.
The original bowls made in the late 60s were hand-laid using epoxy resin and fiberglass cloth. When this proved to take too long to manufacture in quantity, the bowls were then made from polyester resin-impregnated fiberglass cloth (prepreg) and were pressed into the shape in a heated compression mold, which reduced the manufacturing time from hours to minutes.
By all accounts, the earlier, hand-laid epoxy bowls produce/produced a superior sound, which is why this is still the preferred method to make a bowl.
Because epoxy resin is structurally stronger than polyester resin, the thickness of the bowls had to be increased, which also increased the weight of the bowls. At some point, a reduction in weight was sought, which resulted in the use of micro-balloons. (phenolic microspheres) Naturally, since the micro-balloons result in less resin usage because they are a filler, their usage not only reduced weight, but also cost because their usage also means less resin is used for each bowl.
Presumably, this usage of micro-balloons did not further degrade the sound projection/vibration capability of the bowls, but as I say, according to what I've read and heard the hand-laid epoxy bowls are better sounding than the compression-molded polyester prepreg bowls.
True, all the bowls are made in the US, but not all US bowls are made equal.
Wow, thanks. That's actually really interesting as well as being helpful. Would it be correct to assume that hand-laid bowls might have a greater degree of variation than a prepreg lay up? |
|
| |
|
Joined:
June 2012
Posts: 2339
Location: Pueblo West, CO | Grinna - 2012-11-01 3:49 PM
Wow, thanks. That's actually really interesting as well as being helpful. Would it be correct to assume that hand-laid bowls might have a greater degree of variation than a prepreg lay up? From what I read in The History of Ovation Guitar, they first tried two molds: male and female. The book didn't talk too much about the female molds but did describe in enough detail about the male molds for me to understand the process based upon my experience with composites. They would basically use the standard method of waxing the mold, then wetting it with epoxy, then laying the cloth on and forming it to the shape of the bowl. Then they would brush on more epoxy and add another layer of cloth. Lastly, they would put on a layer of plastic sheet, then grease it with Vaseline and then apply vacuum. They then squeegeed out the excess epoxy so they had a high cloth to resin ratio. Technically speaking, you can only get so much resin out because the layers of cloth can only be squeezed down so much before it becomes incompressible. So, you would be able to get pretty consistent pieces out of this type of molds because of the vacuum. Non-vacuum molding would produce more inconsistent parts thicknesses because there's nothing squeezing out the excess resin. It's a lot easier to do this sort of work on a male mold than a female one because it's a lot harder to do this with a cavity mold. The prepreg compression molds have a male and female mold in a hydraulic press, which, when closed also form a consistent thickness, because they've been machined accurately, which I would presume a company like Ovation would do. (See: Ovation Factory Tour 1984 USA) Dan
Edited by DanSavage 2012-11-01 7:00 PM
|
|
| |
|
Joined:
December 2004
Posts: 1673
Location: SoCal | ...search on, bowl construction. This might help. http://ovationfanclub.com/megabbs/forums/thread-view.asp?tid=26395&posts=13&highlight=fiberglass%20bowl%20&highlightmode=1#M344295 |
|
| |
|
Joined:
August 2007
Posts: 1008
Location: Tuscany, Italy | dwg preacher - 2012-10-31 10:17 PM
Lifted from a current thread in the luthiery department:
"" Hi, I just picked up a 1967 shiny back.......
The neck is wonderful feeling and the frets show minimal wear. The sound is really good - way better than my newer Celebrity series. ""
There you go. Independant corroboration from one not previously involved in this discussion.
I own a db shiny bowl too and sound terrific, but it also depends to what kind of celebrity you are comparing it. I recently got a CC67 built probably in the late '80 that sound fantastic (spruce top - deep bowl - mod - A bracing) that compared with a more recent celeb., a CS247 (maple top - mid-depth bowl - quintad bracing) it sounded dull to me (and I sold it). I know, is like comparing oranges with bananas ...
I mean, not all the Celebrity out there sounds like s..t. |
|
| |
|
Joined:
August 2009
Posts: 381
Location: Miami | He doesn't want an answer to any question. He just wants to chat. (His words, not mine). And apparently, we all want to chat too (myself included). But I'm done. I offered to satisfy his curiosity but he said maybe some other time.
'nuff said.
Later all. |
|
| |
|
Joined:
June 2012
Posts: 2339
Location: Pueblo West, CO |
Thanks for the link. The information posted about the hand-laid bowls was taken from the same source I quoted, i.e.: The History of Ovation Guitar.
Lyrachord is simply a trademark given to the composite material used for the bowls on Ovation guitars. The actual material used has changed over the years, though the name used for it has remained the same. Originally it was epoxy resin. (See: US Patent 3,474,697 "...the body is made from plies of glass fabric pre-impregnated with epoxy resin and laminated to a thickness of approximately 0.036 inch...")This was later changed to polyester resin. (See: Ovation Factory Tour 1984 USA, page 52 "...Ovation body bowls are molded in a heated, chrome-plated compression molding die. The press has a 300-ton compression capacity, and the temperature is over 300º. The molding material is a polyester resin/Fiberglass combination, which comes on a roll that must be kept at temperatures under 40º until it is molded...") I have read the references on this site to the most recently produced bodies being injection molded. I would like to know more about the process, but in searching online I haven't found any 'official' information about it. Dan
Edited by DanSavage 2012-11-02 10:31 AM
|
|
| |
|
Joined:
December 2001
Posts: 7237
Location: The Great Pacific Northwest | DanSavage - 2012-11-02 8:21 AM Thanks for the link. The information posted about the hand-laid bowls was taken from the same source I quoted, i.e.: The History of Ovation Guitar. Lyrachord is simply a trademark given to the composite material used for the bowls on Ovation guitars. The actual material used has changed over the years, though the name used for it has remained the same. Originally it was epoxy resin. (See: US Patent 3,474,697 "...the body is made from plies of glass fabric pre-impregnated with epoxy resin and laminated to a thickness of approximately 0.036 inch..." ) This was later changed to polyester resin. (See: Ovation Factory Tour 1984 USA, page 52 "...Ovation body bowls are molded in a heated, chrome-plated compression molding die. The press has a 300-ton compression capacity, and the temperature is over 300º. The molding material is a polyester resin/Fiberglass combination, which comes on a roll that must be kept at temperatures under 40º until it is molded...") I have read the references on this site to the most recently produced bodies being injection molded. I would like to know more about the process, but in searching online I haven't found any 'official' information about it. Dan If I recall correctly from the tour, they still use the high-preassure mold as referenced above but the actual material used, the stuff that comes on a roll, has more glass bead content resulting in the new lighter bowl. The best place to find the specific info would be to find a video of the factory tour from the year after the LX series was released. 2005 maybe? Not real sure on the date. But Rick Hall explains the new bowl at some point. |
|
| |
|
Joined:
January 2009
Posts: 1249
Location: Texas | So, over the years, as bowl composition has "evolved", is there any opinion whether it has affected projection or tone, for the better? I imagine it is pretty hard to determine, as bracing, soundboard design and composition has "evolved" also. I understand it is a sum of the parts...but was just wondering if Ovation bowls have actually improved the tonal response. |
|
| |
|
Joined:
April 2010
Posts: 823
Location: sitting at my computer | amosmoses - 2012-11-02 12:07 PM I imagine it is pretty hard to determine, as bracing, soundboard design and composition has "evolved" also. Agreed. Seems to me with so many variables in each model, it's a lot like comparing apples to oranges to mangos. Were the bowl changes mainly for tonal improvement or for weight reduction?? Are there any published test results? |
|
| |
|
Joined:
June 2012
Posts: 2339
Location: Pueblo West, CO | mileskb - 2012-11-02 8:52 AM If I recall correctly from the tour, they still use the high-preassure mold as referenced above but the actual material used, the stuff that comes on a roll, has more glass bead content resulting in the new lighter bowl. The best place to find the specific info would be to find a video of the factory tour from the year after the LX series was released. 2005 maybe? Not real sure on the date. But Rick Hall explains the new bowl at some point. Thanks for the info. I searched and found the links to the videos you mention, but unfortunately, Waskel's original 41-minute video that Old Man Arthur put on YT is long-gone. (See: 2005 Ovation Factory Tour on YT -- 41 min Long) I sent Waskel a PM asking if he still has any of the original DVDs he produced. Thanks again, Dan |
|
| |
|
Joined:
June 2012
Posts: 2339
Location: Pueblo West, CO | amosmoses - 2012-11-02 9:07 AM
So, over the years, as bowl composition has "evolved", is there any opinion whether it has affected projection or tone, for the better? I imagine it is pretty hard to determine, as bracing, soundboard design and composition has "evolved" also. I understand it is a sum of the parts...but was just wondering if Ovation bowls have actually improved the tonal response.
I don't own a guitar with a hand-laid bowl and I only played one recently for about 30 minutes in a fairly noisy environment so it would be difficult for me to make an accurate assessment, but according to those 'in the know', the hand-laid bowls sound better.
Based upon their assessment, it sounds to me like the projection/tone quality went down when they went to the thicker, heavier, polyester resin, compression-molded bowls.
And, this makes sense to me. The thinner, hand-laid bowls would be more sensitive to the vibrations of the top and thus, would resonate more and as a result produce a better quality sound.
Edited by DanSavage 2012-11-02 3:26 PM
|
|
| |
|
Joined:
June 2012
Posts: 2339
Location: Pueblo West, CO | SOBeach - 2012-11-02 10:04 AM Were the bowl changes mainly for tonal improvement or for weight reduction?? Are there any published test results? Based upon what I've read, neither. It was done to reduce production time and based upon what I know about fiberglass resins; material cost. The early hand-laid bowls were light and responsive, but were relatively time-consuming and expensive to produce. Then, they went to the polyester prepreg, which were heavier, and thicker, and thus probably less responsive, but were able to be produced more quickly because they didn't require the hand layup of the earlier epoxy bowls. As near as I can tell from my reading, this method of production was the norm throughout the 70s, 80s and 90s. According to what Miles says, they're still using the same compression molding, but are using a different composition of prepreg which has micro-balloons mixed into the resin to reduce the weight. The micro-ballons are a filler that allows you to reduce the weight of a composite structure because they displace a given amount of resin with air. Because we don't have any hard data on the exact ratio, it's impossible to say whether this improves or degrades the sound quality. If I were to hazard a guess, I would say that it's about the same as the earlier composition, just lighter in overall weight and probably cheaper to buy since there's less resin in the mix and resin is more expensive than micro-balloons.
Edited by DanSavage 2012-11-02 3:46 PM
|
|
| |
|
Joined:
January 2009
Posts: 1249
Location: Texas | Any idea what year they transitioned from hand laid? Were those just the shiny bowls? |
|
| |
|
Joined:
June 2002
Posts: 6202
Location: Phoenix AZ | They still make hand laid bowls on some models. |
|
| |
|
Joined:
January 2009
Posts: 1249
Location: Texas | They still make hand laid bowls on some models. I hate to even ask this but... just not out of the same material as the old hand laid bowls? |
|
| |
|
Joined:
June 2012
Posts: 2339
Location: Pueblo West, CO | I think a better question would be is whether the new hand-laid bowls sound as good as the original ones. |
|
| |
|
Joined:
October 2005
Posts: 4073
Location: Utah | amosmoses - 2012-11-02 11:07 AM
So, over the years, as bowl composition has "evolved", is there any opinion whether it has affected projection or tone, for the better? I imagine it is pretty hard to determine, as bracing, soundboard design and composition has "evolved" also. I understand it is a sum of the parts...but was just wondering if Ovation bowls have actually improved the tonal response.
My experience is limited, but it seems the handlaid bowls are louder. I have only played deep bowls in the handlaid fiberglass, an original slot head Adamas and my Ovation Patriot. In the modern injection molded bowls I've played a number of the mid, deep, and deep contour bowls. As you mention, the other factors such as materials, bracing, etc are factors confounding a decisive tonal comparison. I think the hand laid bowls may project a bit more sound towards the player, or they just vibrate more and are louder all around. People frequently mention how the hand laid bowls rumble against the body. Perhaps that is a function of the old style glass fabric vs the current glass beads. My perception is that the newer bowls are crisper in the highs, but that could be a function of the LX generation designs vs the older designs (bracing, neck, finish, etc).
The less expensive current production method allows the use of better materials and workmanship for a constant price point. So from that standpoint one could argue the current technology is better sound for the $. If $ were no object and if I were custom ordering a guitar, I would go with the hand laid bowl just for the historical geek factor and the tummy rumble it gives.
In a true apples - apples comparison I don't know that one would sound "better" than the other. |
|
| |
|
Joined:
December 2001
Posts: 7237
Location: The Great Pacific Northwest | Talk about variables and comparing old vs new... Even the finishes have evolved. I'll relay a generic version of this story to keep names out of it, but in the early 2000's an artist brought one of his guitars into Ovation for repair. They noticed it sounded significantly different (not better or worse, just different) than the current version of the same model at the time. A LOT of research went into finding out why and it turned out that over the years, very subtle changes with the most significant being the glues and finish. It didn't happen all at once. At one time they switched glues to a better more ecofriendly glue and change wasn't really noticeable, use different paint, and any change wasn't really noticeable, etc etc.. There are a lot of chemicals involved in building an Ovation. They worked on it and resolved the issue with either changes to the chemicals or thicknesses and amounts, but it was an interesting study in that you really can't compare two guitars from different places and times. They are different. Probably why so many of us own so many guitars. |
|
| |
|
Joined:
October 2009
Posts: 133
Location: Ohio | I say that for the price, they are great guitars. They sound good and play pretty well. That said, I would never buy one new because almost all my guitars are US made and I don't want to support the exportation of jobs from the US. |
|
| |
|
Joined:
December 2001
Posts: 10583
Location: NJ | interesting how if you look at the ford model T and the current ford line up you will find that the cars have evolved and changed.
look at the original ovation line up and the guitar now and you will find they evolved.
why is it we are more open to change in the car industry as opposed to the guitar industry? |
|
| |
|
Joined:
March 2002
Posts: 15678
Location: SoCal | I agree with you Al, but isn't it interesting that Martin and others, while coming out with new forward looking product, also build vintage instruments..... |
|
| |
|
Joined:
January 2009
Posts: 4535
Location: Flahdaw | I may be wrong (usually am) but didn't Ovation really make it's mark in the early years due to their electronics. Everybody who was anybody played an O 'cos no other manufacturer came close when it came to building a stage ready acoustic. It wasn't the unplugged "tone" of these Balladeers, although they sounded fine. It was the electronics.
Now there is huge demand for vintage Martins and Gibsons because of their natural tone. But Ovation can't hope to have big demand for a vintage line of guitars today based on the 70's tone OR the early 70's electronics. Today's electronics blow them away, and the tone (while unique and pretty good) is NOT stellar. As someone already pointed out, Ovation has built reissues, and they didn't do well.
|
|
| |
|
Joined:
June 2002
Posts: 6202
Location: Phoenix AZ | BINGO. |
|
| |
|
Joined:
April 2010
Posts: 823
Location: sitting at my computer | darkbarguitar - 2012-11-05 2:30 PM ...but didn't Ovation really make it's mark in the early years due to their electronics. Maybe so, but when I first played an Ovation (Legend) in '76, I thought it sounded pretty darn good unplugged (especially compared to anything I'd found for the same price). The electronics were icing on the cake to me. IMO the (then unique) round back was quite comfortable, and the neck and fretboard were great!! I liked it so much I bought it and still own it today.
As someone already pointed out, Ovation has built reissues, and they didn't do well. but have any Ovation models been selling so "well"? Kinda tough to spark a buying frenzy based on the (limited) offerings I've seen hanging on the store walls. IMHO YMMV
|
|
| |
|
Joined:
January 2009
Posts: 4535
Location: Flahdaw | '76 was about the 1st time I ever played an Ovation too. I was dazzled by it, but mainly because I had seen them all over the Midnight Special and every other show that had live bands. In truth, I don't really know what I would have thought if I played an old Balladeer and a Martin D-28 side by side back in 1976. For the price they were very good, but good enough to start a whole "vintage collection" today and expect great results??? Probably not. |
|
| |
What's the verdict on non-US made Ovations?
