an open baffle with altec 605a ?

[better]

hello, i need some info... and help i am useing the 605a (8ohm)
in my ob l.s. like yamamoto ob l.s.
and i need to know1) what kind of xover i can use
2)if someone can recom... about capic, resis ect..
at the top of the open baffle i am useing [horn tweeter pionner -pt 410]
with 2.2uf
thanks
better

[jackgiff]

Sometimes a new person asking for help gets a very bad reception on this forum, but don't take it to heart. There are some nice people on this site.

The 605B has a 1600 HZ recommended crossover, but a quick search in the library didn't give me any info on the 605A. Maybe someone knowledgable about Altec will chime in.

Sorry I couldn't help.

Jack Gifford

[moldyoldy]

Try a visit at Jeff Markwart's site;

http://home.earthlink.net/~jmarkwart/

He's done modernized versions of many Altec Duplex XOs, including a phase-coherant version for the 605A/B. All the info you need to build some optimized XOs.

I don't know of many members here that are into the open baffle thing, and all I know about them could fit behind one...that said, (most) Altec 12s and 15s, including Duplexes, need to 'feel' a signifigant load, so unless an open baffle is ~wall-sized, they'll become non-linear at very low levels. Keep in mind I've never heard one though...

For your tweeters, I'd wait to see where the 605s roll off when your XOs are done. You'll probably want to bring them in considerably higher than Pioneer did, which is a very good thing, as diaphragms for them are long gone. I've got a set of early Fukuin PT horns I haven't got to mess with yet, but from appearances, they're very well-built.

Let us know how it works out!

[better]

Sometimes a new person asking for help gets a very bad reception on this forum, but don't take it to heart. There are some nice people on this site.

The 605B has a 1600 HZ recommended crossover, but a quick search in the library didn't give me any info on the 605A. Maybe someone knowledgable about Altec will chime in.

Sorry I couldn't help.

Jack Gifford

thank to you jack; iwill work on

[better]

Try a visit at Jeff Markwart's site;

http://home.earthlink.net/~jmarkwart/

He's done modernized versions of many Altec Duplex XOs, including a phase-coherant version for the 605A/B. All the info you need to build some optimized XOs.

I don't know of many members here that are into the open baffle thing, and all I know about them could fit behind one...that said, (most) Altec 12s and 15s, including Duplexes, need to 'feel' a signifigant load, so unless an open baffle is ~wall-sized, they'll become non-linear at very low levels. Keep in mind I've never heard one though...

For your tweeters, I'd wait to see where the 605s roll off when your XOs are done. You'll probably want to bring them in considerably higher than Pioneer did, which is a very good thing, as diaphragms for them are long gone. I've got a set of early Fukuin PT horns I haven't got to mess with yet, but from appearances, they're very well-built.

Let us know how it works out!

i will let you know now i am replaceing the dynaco st 70 and iwill try to work with quad ii classic 15wx2 (an old one)

[tgroendahl]

Hello Better!

I also use Altec Duplex 605 (B version) in open baffles with the size 120 x 110 cm, and it sounds very nice indeed. I use a modified Audio Note Mesihu Phono SE tubeamp with 2A3 tubes. The sound is warm, very detailed and very natural. I only play LP´s on an EMT 930 turntable. The bass don´t of course go very deep, and I do plan to experiment with some sort of large enclosures in the future.

When I got my Duplex 605B from an eBay seller in Canada, they came with the original N-1600-C cross over. On the forums http://www.hostboard.com/cgi-bin/ult...b=forum&f=3729 and this one http://www.audioheritage.org/vbullet...php/t-622.html I found both the diagram and discussions on the filter.

I have copied the original filter with components that I think sound very good: Cobberfoil - paper in oil - phenolic paper encased capacitors from https://audio.jensencapacitors.com/products/cappatube/ and the 1mH inductor from http://www.riviera-acoustics.com/cat...56&language=en For damping the HF section I use vintage carbon resistors with fixed values (according to the diagram) instead of the L-pad. The series resistor can be bypassed with a capacitor to enhance HF level, here I use a 1 uF cap of the same kind as mentioned. I don´t feel that I miss any HF extension.

With this filter sound has become much better than with the original filter. Some time I will also try to make the Markwart filter.

A lot of info on the legendary Duplex drivers can be found on these forums: http://www.hostboard.com/cgi-bin/ult...b=forum&f=3729 and http://www.audioasylum.com/cgi/etv.mpl?forum=hug

Greetings

Thomas

[Tom Brennan]

605s are most excellent speakers. My 605As do the imaging thing better than my Nineteens do, making an image that wraps around the sides of the listener and with great depth.

Mine are in Barzilay bass reflex cabinets and bi-amped with an ART crossosver at 1700hz; big-hog QSC on the woofers and a Teac Tri-path on the treble. The compression drivers have new 8 ohm GPA diaphragms and I use a compensation network.

[better]

Hello Better!

I also use Altec Duplex 605 (B version) in open baffles with the size 120 x 110 cm, and it sounds very nice indeed. I use a modified Audio Note Mesihu Phono SE tubeamp with 2A3 tubes. The sound is warm, very detailed and very natural. I only play LP´s on an EMT 930 turntable. The bass don´t off course go very deep, and I do plan to experiment with some sort of large enclosures in the future.

When I got my Duplex 605B from an eBay seller in Canada, they came with the original N-1600-C cross over. On the forums http://www.hostboard.com/cgi-bin/ult...b=forum&f=3729 and this one http://www.audioheritage.org/vbullet...php/t-622.html I found both the diagram and discussions on the filter.

I have copied the original filter with components that I think sound very good: Cobberfoil - paper in oil - phenolic paper encased capacitors from https://audio.jensencapacitors.com/products/cappatube/ and the 1mH inductor from http://www.riviera-acoustics.com/cat...56&language=en For damping the HF section I use vintage carbon resistors with fixed values (according to the diagram) instead of the L-pad. The series resistor can be bypassed with a capacitor to enhance HF level, here I use a 1 uF cap of the same kind as mentioned. I don´t feel that I miss any HF extension.

With this filter sound has become much better than with the original filter. Some time I will also try to make the Markwart filter.

A lot of info on the legendary Duplex drivers can be found on these forums: http://www.hostboard.com/cgi-bin/ult...b=forum&f=3729 and http://www.audioasylum.com/cgi/etv.mpl?forum=hug

Greetings

Thomas

thank you now i am useing the quad clasic ll (6L6) its good but the mid?
better

[better]

605s are most excellent speakers. My 605As do the imaging thing better than my Nineteens do, making an image that wraps around the sides of the listener and with great depth.

Mine are in Barzilay bass reflex cabinets and bi-amped with an ART crossosver at 1700hz; big-hog QSC on the woofers and a Teac Tri-path on the treble. The compression drivers have new 8 ohm GPA diaphragms and I use a compensation network.

pls i like to know more about the crossover

thanks better

[tgroendahl]

thank you now i am useing the quad clasic ll (6L6) its good but the mid?
better

Shalom!

I have only heard the Quad II on a few occations, but as far as I know, it is regarded as a very fine amp. What did you mean by "mid"?

Lehit.

[jblwolf]

Hello,I had to jump into this thread,one of the first speakers I had was a 605b,open back cabinet,what was interesting about the open back was inside of the cabinet,it had layered frames with some type of wool tacked to each frame,they had about 6 frames,each frame had a single hole 15"-12"-10"-8"-6" and the last frame was covered with a soild sheet of wool.the gent I got them from said he built them in 1966,I also picked up the amp/preamp that he built,it was a knightkit,maybe 15 watt(mono)it was one of the sweetest sounding mono system that I ever had.I think the wool was used for damping,wish I'd taken pictures that little system roared(it had a stock x over)

[tgroendahl]

Hello,I had to jump into this thread,one of the first speakers I had was a 605b,open back cabinet,what was interesting about the open back was inside of the cabinet,it had layered frames with some type of wool tacked to each frame,they had about 6 frames,each frame had a single hole 15"-12"-10"-8"-6" and the last frame was covered with a soild sheet of wool.the gent I got them from said he built them in 1966,I also picked up the amp/preamp that he built,it was a knightkit,maybe 15 watt(mono)it was one of the sweetest sounding mono system that I ever had.I think the wool was used for damping,wish I'd taken pictures that little system roared(it had a stock x over)

Hello Jblwolf,

Thanks for your interesting post! That "open back" cabinet you describe makes me very curious. Would it be a kind of an "aperiodic box"? (http://melhuish.org/audio/DIYBX4.html)?

Would you be able to post a little sketch of the cabinet with size and dimensions as you recal it?

I would like to experiment with enclosures for these wonderful Duplex drivers. One of the reasons I have chosen to stay with an open baffle for a while (with the lack of level in the lower octaves due to the drivers quite low Qts) is, that the sound is just so relaxed and involving. Many BR cabinets sounds in my ears "boxy" and has colorations compared to an open baffle.

Thomas

[Tom Brennan]

Many BR cabinets sounds in my ears "boxy" and has colorations compared to an open baffle.

That's called "bass".

[jblwolf]

Hello tgroendahl,
I wish I knew how to make a sketch on a computer,the person that I got speaker from is still around,he was a member of my moms gardening club,so Ill see if I can get in touch with him,all I remember was it was something of a lowboy design,I know because I had it in front of a window in the apartment. I had at the time,so it would have been maybe 24"high,the window was about 56"wide and it wasnt that wide maybe 30"-36" and about 20"-25"deep.besides the great sound it put out,we would also sit on it and lookout the window to girl watch since the window faced a bar across the street and was on a main street(early-mid'70's-Detroit) with something always going on.SWEET

ANYONE REMEMBER THE RED CARPET ON E.WARREN-DETROIT????

[tgroendahl]

That's called "bass".

Hello Tom,

I certainly get your point, and must admit that I have not so far heard any original Altec speaker, since the "19" and the other legendary designs are unfortunately extremely rare in Denmark. There has been hifi/professional JBL distribution here over the years, but for some strange reason not the great Altec gear.

It´s my plan to make large enclosures for my 605B´s, but I´m still considering the type of cabinet, and I would not mind to experiment. (I am aware that the Qts of most Altec drivers is not suitable for OB, the Biflex 420 probably better with a Qts of around .50)

After I sold my Audio Note ANE (silver edition) speakers a few years ago, I have been experimenting with different vintage drivers (ELA Philips, Klangfilm, etc.) in open baffles. The sound is very involving and "seductive" in combination with an 2A3 SE amp. On this website is a photo I have supplied of my own 2278 driver: http://www.bmw2002.nl/philips.html and also drawings of the huge original open baffles and frontloaded horns designed for use in cinema. This is another site with wonderful vintage drivers: http://www.german-vintage-loudspeake...vid.1/home.htm

Greetings

Thomas