15' Bass-Scoop Rear Horn Loaded Cabinet. I am building a bass bin with 15' speakers and i was looking for a design that has the speaker go inside so that it is they are not visble from the outer part of the box is that possible or its a crazy imagination help me with one if you have an idea. I still have two sets of these components, but.
A place to discuss DIY audio, share plans and schematics, and link to interesting projects. I posted some pictures in and got a lot of feedback and questions regarding my speakers and someone suggested to post them here. Well, I'm here to deliver.Pictures of building and some nice shots at the end:The speakers are based on a plan by Berndt Burghard called 'Das Viech'. The plan is very popular in the DIY-HiFi-scene here in Germany.
There are many thousands of builds, what resulted in the longest thread (nearly 13k posts at the moment) in the biggest german HiFi-board. Originally the designer intended to use very cheap fullrange drivers, but the plan is so damn good it's also used by many builders for high-end drivers.I started this project in March 2010 and was finished few weeks later, but without a paint job.
Instead of the suggested '8AG/N' by 'Beyma', I bought better drivers: '8 D 1,5 CS' by the italian manufacturer 'Sica'. These are very decent speakers for about 60€ each. They are much better than the Beyma, especially for high frequencies, I had a lot of fun with them.For wood I used 19mm medium-density fibreboard.
About 2m² for each speaker. Because of the horn layout the build was quiet time-consuming to allign all the boards and glue them, but doable for everyone with at least a quant of woodworking skill.
I spent about 100€ for each speaker back then (with driver and other parts).The designer wanted to create a speaker with very high efficiency and low costs. Well, he succeded.
They reach more than 120dB easily.
First off a very big thank you to Yeo of for lending me a pair of his Coral 8A-40s to audition in my Dallas III cabinets. I was initially surprosed at how small the light the Coral 8A-40 drivers were compared to the Fostex FE206E.
I understand that full range driveres depend on massive acceleration of the cone to deliver the entire range of frequency, so I wondered how Coral 8A-40's smaller magnet would compare to the Fostex206E's massive magnet that is at least 3 times larger and heavier? I met Yeo one fine sunny weekend in January 2008, at his house. I took the opportunity to listen to his setup, the Coral Beta 6s in Hedlund cabinets. In terms of height the hedlunds are indeed an imposing pair of speaker, enough to give the 'Tim the Toolman Taylor' in any of us the argh argh argh.
But in real terms, both the Hedlunds and the Dallas III cabinets are similar in size, Hedlunds being a single fold horn and the Dallas III is a double fold horn. Once Yeo got his system up an running, we played some Led Zeppelin and cranked up the volume.
Wow those speakers ROCK. They played loud and fast. That said, the first thing that hit me as odd was that the high frequencies were missing. Thus a lot of the 'ambiance' in the music was lost. I would have loved to stay the entire afternoon and flip through different genre of music to see how the speakers would fare but I was in a rush. I listened to the speakers for less than 15 minutes in total.
I know this is too short a time to form any real opinion. Here are the Fostex FE206E and the Coral 8A-40 front view. The Coral drivers a bit dirty as they are vintage stock.
Now to my Fostex FE206E in Dallas III cabinets, I had the speakers installed in the cabinets for over 4 months now and I have been listening to them almost daily. I play music through them every evening even if I don't intend to sit down for a listen, just to give everything a daily workout.
The wire leads were still sticking out of the cabinets in an unsightly manner. Not only is this unsightly, Ron, the Dallas III designer has said to me that this would cause a loss in the horn efficiency which translates to its ability to play low and loud. Well its because the wires will prevent an air tight seal between the drivers and the cabinets. But still I procrastinated, I left the speakers unfinished because it sounded so good to me.After some urging from my other half, I decided it was high time I finished off the speaker and tested the Coral 8A-40s that Yeo was gracious enough to loan to me. So I installed a pair of binding posts to clean up the wire mess. And I installed rubber gaskets so that I could create an air tight seal for the drivers and the cabinet.The first order of business was to test the Coral 8A-40s.
Being new old stock, I was conscious of the fact that the drivers would not sound their best initially. And as I had already surmised they did not sound good at all initially. I left them playing off and on for about 2 weeks. I estimate that the drivers must have played about 50-60hours. I could tell that they were improving. Even my other half commented that the speakers sounded good. With this affirmation I thought it was time for me to sit down for a listen.The Coral 8A-40s sounded very similar to the Coral Beta 6s.
Guess there is a family resemblance. These drivers can rock, put in some classic rock and you are good to go. Put on some slower Jazz numbers and I discovered that the vocals were good too. Music was 'fast' and 'tight'. However, the drivers exhibited the same high frequency roll off, just like its more sort after brethren, the Coral Beta 6. And like I said earlier, the music was missing some ambiance. I could not get used to this especially when I had an pair of ESLs that excelled in this department.
I know that there are many who will not agree with my evaluation of the Coral 8A-40's high frequency roll off. But these are what my ears are telling me.
To all Coral owners, you have a gem of a driver, and for the price there is no speaker thant can compare. So out came the Coral 8A-40s and back in went the Fostex FE206Es. If you have been observant, you would have realised that by this time I have been listening to the Corals 8A-40s in my bedroom exclusively for 2 weeks. Other than the High Frequency roll off, I had no other complaints about the Corals. At this point I could not compapare the Coral 8A-40s to my own Fostex FE206Es as I had trouble recalling what the Fostex FE206Es sounded like.As soon as I had the Fostex FE206Es installed, and had music playing through them, I realised that they were a whole order more musical and also clearer compared to the Coral 8A-40s. It was like a veil was lifted. Just the clarity of the music was astounding.
To make sure this was not a figment of my imagination, I swapped between the Corals 8A-40s and Fostex FE206Es a couple of times and even asked my other half to have a listen. And both of us preferred the Fostex FE206Es. However I noticed that the Coral 8A-40s had a slightly fuller mid bass, which made male voices and rock music sound forward. Both drivers played quite low, Corals 8A-40s till about 49hz and the Fostex FE206E till about 43Hz before dropping off. Here is another view of the Fostex and Coral Full Range Drivers.
Not all 8' FR drivers are made equal. The massive magnets does make a difference. And u know what, I slapped on some Def Leppard, Queen, ACDC. The Fostex FE206E in the Dallas III cabinets ROCKED too.
As hard as the Beta 6s in Hedlund cabinets. Since my Uncle helped me a a lot during my various cabinet builds with advise, materials and equipment. I would like to help him out by offering his carpentry services. My Uncle is a very professional carpenter, he was one of the craftsmen that was contracted to restore Tun Mahatir's home and build an attached museum in Alor Setar, Malaysia.
I am offering my Uncle's Speaker Cabinet Building services. Any design required can be made, any wood required can be sourced. If you are interested please send a brief of your project and the plans of the cabinets required to. After clarifying your requirements I shall return to you with a quote and estimated shipping charges. I will ship both domestically and internationally. Cabinets will be shipped in knockdown form to save cost.
Detailed instructions will be supplied.