Altec 2 ways

[GeorgeO]

Re: Altec 2 ways photo

Here's one picture, it's a bit grainy. The horns that I finally went for were black.

 

[prem]

Cool stuff, GeorgeO. When i look at you guys i wish i too had some DIY skills.

 

[GeorgeO]

First impressions after a longish asession yesterday and another shorter one today are that the highs are excellent, with female vocals sounding really good. Good recordings excel and poor ones are shown up. On the bass front I need a powered sub to also be present, the 15 inch paper cones do not deliver all dimensions.

Today I listened over a couple of glasses of Jacob's Creek to a range of female vocals- Nana Muskouri, Sarah McLachlan, Joni Mitchell, ABBA, Reba Macintyre, Bonnie Raitt, Paula Cole, Dionne Warwick, Faith Hill and a few others, yesterday to Norah Jones,Diana Krall and the Carpentes. Without exception they sounded very good. I have a few tweaks and things to do to complete the build to my satisfaction, I was in a hurry to listen to the sound so will finish everything properly, as well as do a few tweaks to improve the sound and then report. I may be travelling for a few days, and the update may not happen until the end of the month. The cradle for the HF unit needs a major redo but that will not happen soon.

Thanks Prem: It's a long, long road, with many a winding turn..

 

[olly42]

Congratulations GeorgeO looks awesome... would love a listen if possible

 

[Naturelover]

Fabulous George! Wish I could hear them. Congratulations!

 

[reubensm]

What a fab build. Surprised at your impressions on the bass front as I thought Altec bass drivers produce thudding bass (my incorrect assumption). Appreciate the honest appraisal.

On another note, if I had my sofa like that betwen the speakers, my little sons would climb up and fiddle away to glory

 

[hydra]

The symmetry-obsessed OCD-goblin in my head is worried about the off-center sofa

The speakers look like they mean business!

 

[GeorgeO]

Actually they do produce bass, the problem is that unless I do some attenuation to compression driver, the highs, though superb, are over powering. The HF units are of much higher sensitivity than the LFs, need to balance them. Until I do that the 12 inch powered sub woofer will have to reinforce the bass. I have got good Dayton binding posts from Parts Express today and installed them, so the box is now good. I will not post any more until it is all done and completed.

 

[keith_correa]

On another note, if I had my sofa like that betwen the speakers, my little sons would climb up and fiddle away to glory

Fiddle-dee-dum and Fiddle-dee-dee... eh? That's what little ones do best. Fiddle with stuff! Not that we, not so little guys do any better. I fiddle away all the time. Just can't leave well enough alone.

 

[rajagopal_j]

The HF units are of much higher sensitivity than the LFs

The 288Ks are rated at 109Db with the standard Altec 311 Horns. With the 450Hz LeCleach horn, you are using, it should go up by at least 10-12Db in sensitivity making it about 120-122Db.

The 416 are rated at 99Db given that you are using a half horn design, that should increase the efficiency by at least 5Db, giving you 105Db for the Lf.

You will have to attenuate at least by 12Db, the efficiency increases are guesstimates, so there is some playing around you will have to do with attenuation. Then there is the sounding /fine tuning of the system, bassier, mid rangy or bright based on your taste/interest in music.

With my 288s and 416 on Open Baffle I attenuate by 6Db.

 

[anilva]

Not nitpicking but decibel is "dB" and not "Db".

Cheers

 

[GeorgeO]

Ok so after inserting L-pads yesterday and attenuating the HF units the sound is now a lot better. The mids and lows are significantly better and I can now listen to music without the sub if I want to. The body, sound stage and detailing is exceptionally good. As reported earlier the highs were outstanding to start with and they continue to excel. At this point the goal is to enjoy the music and the system, not to report daily about breaking in and magical improvements. Suffice it to say that it is an exceptionally good system, and while I have to still do a few small things-like a better cradle to seat the HF units( which I will get accomplished eventually), I am almost there.

 

[GeorgeO]

Update after a week. I've been listening to a lot of different kinds of music-jazz, male vocals, female vocals, blues, classic rock, pop, folk etc to put the system through it's paces. Suffice it to say that it has exceeded expectations.

 

[aks07]

Update after a week. I've been listening to a lot of different kinds of music-jazz, male vocals, female vocals, blues, classic rock, pop, folk etc to put the system through it's paces. Suffice it to say that it has exceeded expectations.

When are you embarking upon Mk2 of this build ?

 

[GeorgeO]

Only after meeting you in November over chai pani and biskoot!

 

[GeorgeO]

I've pulled the trigger on a few more things related to this build-a MiniDSP crossover unit and a chip amp(Peter Daniel board) to bi amp the speakers.There is an EL34 in the pipeline that I am getting fixed, I will use the chip amp in the interim and see how it sounds.As it is, the passive crossover is meeting expectations, I'm wondering if going active is going to exceed expectations!

The journey continues!

 

[GeorgeO]

MiniDSP 2 X 4 version has reached me, now to unbox and learn a little more about its capabilities and see where I can get on my journey towards Nirvana!

 

[malvai]

I've pulled the trigger on a few more things related to this build-a MiniDSP crossover unit and a chip amp(Peter Daniel board) to bi amp the speakers.There is an EL34 in the pipeline that I am getting fixed, I will use the chip amp in the interim and see how it sounds.As it is, the passive crossover is meeting expectations, I'm wondering if going active is going to exceed expectations!

The journey continues!

George, an active crossover, if implemented well, WILL kill it. There is no comparison at all.

 

[GeorgeO]

Ive completed the active crossover using the minidsp, and surprise, surprise-it sounded marginally different, not hugely better! This is my first active crossover, and in sharp contrast to all those who have been tom tomming actives, especially some on this forum, as the best thing on the this planet since sliced bread, I have to say my earlier passive crossover was a pretty good one, and stands very favourable comparison to the new one.

I will need to listen over many hours to see how much better this sounds and also listen with some knowledgeable audiophile friends to decide which way I will finally go.

The mini dsp is a spohistacated and affordable toy, which has huge capabilities, I was lucky to get someone who has one for some time and is very familiar with its features to come over and take measurement using pink noise and sweeps, and then do some tweaking.The journey is far from over, but sure as hell, this ain't the Holy Grail!

 

[anilva]

Ive completed the active crossover using the minidsp, and surprise, surprise-it sounded marginally different, not hugely better! This is my first active crossover, and in sharp contrast to all those who have been tom tomming actives, especially some on this forum, as the best thing on the this planet since sliced bread, I have to say my earlier passive crossover was a pretty good one, and stands very favourable comparison to the new one.

I will need to listen over many hours to see how much better this sounds and also listen with some knowledgeable audiophile friends to decide which way I will finally go.

The mini dsp is a sophisticated and affordable toy, which has huge capabilities, I was lucky to get someone who has one for some time and is very familiar with its features to come over and take measurement using pink noise and sweeps, and then do some tweaking.The journey is far from over, but sure as hell, this ain't the Holy Grail!

George, in defence of the active cross over, all I can say it is a tool that is in your hands (particularly mini DSP) which lets you tweak the sound you like. It has no character of it's own unlike passive crossovers and take any personality. We can do the listening. Pink noise sweeps and machine based adjustments are not going to yield any good sound. The tweaking has to be done by the ear. I think I can say with little bit of authority on this subject than most others.

Cheers