My DIY Altec Lansing A7 - Voice of the Theater

[anilva]

Went yesterday over to Santhosh's place. There were fellow members Rajiv and kuruvilajacob too. We had a good listen to Santhosh's revised setup with Lyrita and the Ortofon SL-15 cartridge on Lenco L75.

The setup sounded quite well and had the stamp of Altec sound to it. Nice and easy and lot of dynamics. Now that the other components are in place and the project has moved from experimental to production phase, IMO, the present crossover which consists of just Russian caps to the HF needs to be overhauled to a more comprehensive one. The 416A LF are currently being driven fullrange, which is not a good thing and is adding coloration to the overall sound. The crossover point needs to be tweaked for better balance.

Santhosh did roll the tubes from 2A3s to 45s and back. I preferred the 45s. The dynamics and balance is better on 45s in his setup. Also there seems to be some channel imbalance on 2A3s, which all of us noticed.

We also listened to his new Shiva subwoofer build. It was pumping out huge amount of solid clean bass. Well done Santhosh.

Thanks for the invite and for some good time with friends.

Cheers.

 

[santhosh]

Thanks Anil, it was a pleasure to have you all over.

Will get the inductors done fairly soon. With the 288s entering the chain soon and at a lower crossover point, the overlap will be even more.

I did not get a chance to troubleshoot the 2A3s after the meet. I had swapped tubes the previous night and may not have fitted them properly which might be causing the channel imbalance. Will do today.

 

[stevieboy]

Wish i was there. But with the weather cancelled other plans and just stayed at home. Will be interesting to see how the full crossover changes the sound!

 

[grubyhalo]

Sounds like a fantastic session. Maybe I should plan my long-pending visit to Bangalore soon...

 

[Rajiv]

Hi,

I spent a very enjoyable afternoon at Santhosh's home on Thursday in the company of fellow forum members Anil and Kuruvillajacob.

Santhosh's system is sounding good,but as Anil has mentioned there are a few rough edges .

The first priority is to finalise the crossover,and next is to adjust the port tuning.

The big Altec multicell horns shift the tonal balance slightly to the mids while rolling of the highs. There is a slight loss in attack because of the HF roll off.For example snare drums and cymbals sound a little muted. A change to a better crossover design will correct this.

Now that Santhosh has the Altec 288 drivers he can impliment the Hiraga crossover or similar crossovers used by other Altec users that address the problem of HF roll off in the big multicell horns.

Santosh,as I mentioned you can bring in the Altec 802 from around 7-10Khz with a smaller horn like Virens 800 or 1000 Hz LeCleach. You can also run the 802 without a horn when it is used at those frequencies.

Once the crossover issues are sorted out the system will be truly magical. All the requirements(tone,musicality,dynamics,etc) for an outstanding musical system are already present just needs a little fine tuning.

Santhosh if you can over the weekend,try out your DIY sub with the A7's. It should be quite interesting.

I too prefered the 45's to the 2A3 in this system at this point of time ,but then the 2A3's also emphasise the mids .This coupled to the multicell horns doing the same while rolling of the highs made the sound a little dull and midrangey(but not in a bad way) when compared to the 45's which have a leaner tonal signature compared to the Shugang 2A3's.


Regards
Rajiv

 

[corElement]

I too prefered the 45's to the 2A3 in this system at this point of time ,but then the 2A3's also emphasise the mids .This coupled to the multicell horns doing the same while rolling of the highs made the sound a little dull and midrangey(but not in a bad way) when compared to the 45's which have a leaner tonal signature compared to the Shugang 2A3's.

Your description of the Shugang tubes is quite accurate.
I think it's nice that Santosh can swap between the two depending on his mood. The midrange of the 2a3 on a very transparent speaker is quite an experience in itself. I've been listening to linear sound for a while now and recently got to hear the 2a3's and there's just something special about it. A very sweet tonality that makes one forget highs mids and lows and just lets one enjoy the music.

 

[vin_eme]

Went yesterday over to Santhosh's place. There were fellow members Rajiv and kuruvilajacob too.

Cheers.

Santhosh, missed the gathering :-(. Had some last minute work for the travel


______________________
**Wirelessly posted**

 

[prem]

Hi Guys

The 2A3 has no mid range emphasis at least in my system. To me it sounds pretty neutral.

 

[santhosh]

Update:
Have been listening with the 811 horns for about a week while my 805 horns were away for painting. I find that the short 811 horn loads the smaller format 802 driver better than with the larger 805 horns. There is more immediacy, presence and more HF. Seems to work well with the SET amp though I preferred the larger horns with the 802 when I had the Adcoms. Will be getting the diapraghms tomorrow from Steve, so can try the 805s with the 288s. But not sure if I'll be able to get an inductor wound to cross them correctly as there is some work related travel around the corner.

Also the channel balance issue with the 2A3 has gone away, probably had not fitted the tubes properly.

Here are some pics of the painted horns and throats.

Had masked the original Altec Decal before painting:

 

[santhosh]

Hi Guys

The 2A3 has no mid range emphasis at least in my system. To me it sounds pretty neutral.

Spoke to George, he was full of praise for your system and also your collection . Need to plan a visit since your system has changed since my last visit.

Santhosh, missed the gathering :-(. Had some last minute work for the travel

No worries buddy, next time. You have listened to my system few days before, so you mainly missed meeting FMs.

 

[prem]

Hi Santhosh


You are most welcome. The system sounds very different from what you heard the last time. The amp is still breaking in. Think it needs another 50 hrs or so.

 

[reubensm]

Dear Santhosh, the altecs are looking majestic. Not sure if its a great idea to stack your LPs over the ports. Assume it was just an arrangement for the photograph, or did you intentionally place these?

 

[santhosh]

Thanks Prem.

Thanks Reuben, I have placed those LPs there so they cover the bass reflex partially. The original port size of the A7 works very well in a theater scenario where the audience is seated ~30 feet away, so one of the tweaks to improve the bass (quantity and quality) when placed in a smaller area was to reduce the port size. I intend to make another front baffle (it is removable by design) with a smaller port. The LPs are a stop-gap arrangement until then .