A new toy on the anvil

[GeorgeO]

Folks

I am about to start on a new floorstander MTM speaker system( yes, yet another-my wife looks at me as if I've lost my mind) using Scanspeak drivers in an MTM design. The design is from Phil Bamberg, of Bamberg Audio and I have also got the crossover components from him. Will post details and photos as I proceed.

I'm also getting a few more toys to play with during this Christmas season-a WD TV Live, and hopefully an OAudio Bash 500w sub amp for my Shiva.

More later.

 

[deba]

Best of Luck !! )

 

[iaudio]

GeorgeO, I thought you were already working on that build. Anyway, good luck. Which ss drivers if I may ask?

 

[grubyhalo]

Subscribed!

 

[soulforged]

great George sir! :clapping:

How about step-by-step details with pics as the build comes along...will help n00bs like me to see a speaker build in action...

 

[GeorgeO]

Sure.

Here's some more info:

At this time what I can share is that the drivers are a pair of Scan Speak 18W8545K Classics as mids and the D2905 9500 tweeters(MTM). By an error I bought four 18W 8545s instead of the K, and while they are both identical with regard to physical dimension, they perform quite differently. Accordingly I have since ordered 4 8545K replacements which have reached my son in SFO this morning, and will no doubt find their way to Bangalore, in due course of time on the back of some unsuspecting mule.

What happened to the 8545s? They are excellent drivers, and were immediately snapped up by friends who plan to use them in their projects. It helped that I bought them preowned ( and sold) them at a discount! I may use one pair of these drivers as an interim mid while awaiting arrival of my 8545Ks(according to the designer they will work ok, though bass will not be as good). I bought detailed plans to build the enclosures, a custom tweeter baffle plate to replace the original one and the circuit and parts to wire up the crossovers. Terminals are from Parts Express.

With regard to the enclosures, I will post more info once things are a bit more firm.At this point I am considering covering the 19mm MDF with 6 mm rosewood veneered plywood, and do the front baffle and corners using a low cost timber-maybe pine/deal wood. This is almost white and is a nice contrast to the dark of rosewood, and also gives the enclosure an art deco look. The carpenter is out of town and will be back next week when I can make some progress.

I will see if I can post pictures of the bits and pieces.

 

[GeorgeO]

Titus

I have been planning this build for some time, but got sidetracked with doing up my HT room. Also I was short of space-with 3 sets of speakers already wired up in the house and a powered sub on the way, didn't know where this would be placed once it was built.

Now I know!

 

[GeorgeO]

View attachment 5732

View attachment 5733Drivers:

 

[GeorgeO]

Note the machining custom baffle on the tweeters. This allows the tweeters to be placed in closer proximity to the mids on the baffle. I will post pictures of the crossovers after they are assembled.

 

[GeorgeO]

Sorry "machined custom baffle plates". These replace the original ones on the tweeters.

 

[Kannan_madhu]

OMG what happened to the woofer cone

 

[GeorgeO]

Its a Kevlar(18W8545 "K" ) cone the regular 8545 has a slightly different cone, maybe I will take a photo and post a bit later.

 

[doors666]

Its a Kevlar(18W8545 "K" ) cone the regular 8545 has a slightly different cone, maybe I will take a photo and post a bit later.

IIRC the normal ones are paper, the K version stands for (K)Coated.
is it 2.5way or 2way?

 

[GeorgeO]

It's an MTM 2 way floor stander. I'm sorry I should have given the correct answer, that Phil Bamberg gave me when I asked him:

The main difference was aluminum bobbin for the 8545, and K was for Kapton (non-metallic) bobbin with the 8545K. The aluminum bobbin puts in more damping, and thus the lower Qts figure.

 

[doors666]

thanx george. i though all Ks were just coated. I know thats the case with 18w and 15w revs, perhaps the classics are different.

I am also in final phase of selecting a FS. so far looks like it will be ER18 MTM 2way (paul kittinger and dennis murphy, same guys who did most of the salk sound designs). most probably will pull the plug in a few days time assuming I dont change my mind and go for something else. One thing i have found is my plans arent concrete until I have placed the order:lol:

I would like to compare these two some day.

 

[GeorgeO]

It's got the option of being built either ported or sealed. Since all my projects so far have been ported I asked Phil about which route to follow-he recommended I go sealed, so I am going by his recommendation-here's his interesting response:

I added the ported option because there was a time when no one could believe that the woofer was better suited in a sealed box. So I put the port option in there mainly to reduce questions on the issue.

 

[kaushik]

makes me a big fan of GeorgeO.. let there be DIY !

 

[GeorgeO]

Hi Kaushik

Look forward to meeting you in Indiranagar on Sunday.

 

[anilva]

George,

I am having withdrawal symptoms these days, what with no major project on hand. I want to do a large volume scanspeak revelator based floor stander (MTMW). We can discuss some ideas.

Cheers.
Anil

 

[GeorgeO]

Hi Anil

Thats a nice position to be in,let me try and address that asap!

It's well worth auditioning Venu's Acoustic Portrait MTMs sometime to get an idea about what Scanspeak Classics are capable of delivering. Also, why not wait a month until my MTMs are complete? The Revelator is in a different league no doubt.

My son came with my first pair of SS 18W8545Ks( ordered from Madisound) this morning from the US, the cone looks a lot more rougher than the 18W8545. I hope to start work on my MTM soon,but other commitments need to be completed before that!