Hello. Question from Italy. I've got the smallest single ended triode from Line Magnetic, 3+3 watt mini 218ia, driving Altec Lansing coaxial speakers 409-8c, 97 db sensitivity, nominal impedance 8 ohm, minimum impedance 6 ohm.
The speakers sound fantastic but lack deep bass. I read on some forums that for a tube amp I need an active subwoofer with speaker level imputs, and I shoud preserve the "voice" of the tube amp connecting in parallel on the amp speaker terminals the speakers and the sub, in order for speakers and sub to overlap on the low frequencies.
Is that correct? If it is, I have found a used Yamaha YST-Sw45 in Italy at a good price. It is an active subwoofer and has speaker level imputs.
This is the online manual:
https://usa.yamaha.com/files/download/other_assets/2/319752/YST-SW45.pdf
Can any of you tell me what kind of impedance the tube amp will read if I connect in parallel on the amp's speaker terminals the Altec and the Yamaha YST-Sw45? For example, On the same amp's speaker terminal banana plug to the speakers and spades to the sub.
(I will not use the speaker level outputs on the sub, I will let overlap the bass from speakers and sub.)
Or, is there a safer way to connect tube amp and sub?
The speakers sound fantastic but lack deep bass. I read on some forums that for a tube amp I need an active subwoofer with speaker level imputs, and I shoud preserve the "voice" of the tube amp connecting in parallel on the amp speaker terminals the speakers and the sub, in order for speakers and sub to overlap on the low frequencies.
Is that correct? If it is, I have found a used Yamaha YST-Sw45 in Italy at a good price. It is an active subwoofer and has speaker level imputs.
This is the online manual:
https://usa.yamaha.com/files/download/other_assets/2/319752/YST-SW45.pdf
Can any of you tell me what kind of impedance the tube amp will read if I connect in parallel on the amp's speaker terminals the Altec and the Yamaha YST-Sw45? For example, On the same amp's speaker terminal banana plug to the speakers and spades to the sub.
(I will not use the speaker level outputs on the sub, I will let overlap the bass from speakers and sub.)
Or, is there a safer way to connect tube amp and sub?
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You want the voicing to match with the Altecs, but you are where the room dominates.
You want at least 2 subs, and i’d power with a good Class D amplifier,
dave
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Thanks. The room is not very small by italian standards.
We are talking two active subwoofers and a Class D amplifier connected to the Altec and The sub?
The power handling of the Altec is only 16 watt. Are we talking about a very small class d amplifier?
I've got also a push pull cayin tube amp, 10 wpc with el84, and a Nad C316BEE V2, 40 wpc, pretty robust. Do you think I would be better off with the Nad and two subwoofers?
Thanks in advance.
We are talking two active subwoofers and a Class D amplifier connected to the Altec and The sub?
The power handling of the Altec is only 16 watt. Are we talking about a very small class d amplifier?
I've got also a push pull cayin tube amp, 10 wpc with el84, and a Nad C316BEE V2, 40 wpc, pretty robust. Do you think I would be better off with the Nad and two subwoofers?
Thanks in advance.
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I have tried to drive these Altec vintage speakers with two integrated tube amps:
The Cayin, despite driving my Triangle Titus XS much louder than the small Line Magnetic, and with more slam on the low frequencies, can't drive properly the Altec. I need to put the volume knob at 9 o' clock and further to get something.
The small single ended Line Magnetic, 3wpc, drives the Altec a lot louder than the Cayin and with more authority, with the volume knob at only 8 o' clock.
I have also tried my Nad, but the tiny Line Magnetic single ended is the only one that drives properly these Altec.
So, if I purchase one or two subwoofers, it's going to have to work with this tiny Line Magnetic.
My question is: If I connect in parallel the Altec speakers and a powered subwoofer on the same speaker terminals of the tube amp (using the speaker level imputs of the sub) what kind of impedance would the tube amp read? Could I have impedance problems?
Thanks in advance.
- a Cayin push-pull MT-12n with EL84, 10 wpc
- a single ended Line Magnetic Mini 218ia, 3 wpc.
The Cayin, despite driving my Triangle Titus XS much louder than the small Line Magnetic, and with more slam on the low frequencies, can't drive properly the Altec. I need to put the volume knob at 9 o' clock and further to get something.
The small single ended Line Magnetic, 3wpc, drives the Altec a lot louder than the Cayin and with more authority, with the volume knob at only 8 o' clock.
I have also tried my Nad, but the tiny Line Magnetic single ended is the only one that drives properly these Altec.
So, if I purchase one or two subwoofers, it's going to have to work with this tiny Line Magnetic.
My question is: If I connect in parallel the Altec speakers and a powered subwoofer on the same speaker terminals of the tube amp (using the speaker level imputs of the sub) what kind of impedance would the tube amp read? Could I have impedance problems?
Thanks in advance.
no you need a seperate sub fed from the preamp out with a class D amp to power it. That is needed to work with your existing setup. Good class D amps (top of the line) are those from Hypex and Purifi. Both do sell diy boards, but ther are also many commercial builds from those, from the more expensive NAD power amps to relative cheap basic builds by Buckeye (US) or Audiophonics (France). Both cheap brand have a very good reputation on sound and build but don't look fancy like a NAD M23 or so...
If you want a sub with tube amps, that is a very expensive and hard to do thing. You need high power tube amps, that cost a lot to build/buy, and even more to maintain. You will also need quiet some technical skills or a fulltime engineer to do that. But sub with a class D amp is way more controlled and easier to do and you won't mess up the sound, because tubes only add distortion to sub, not a warm organic sound like higher up (also trough distortion, but the kind we like). A good sub needs at least a 100w (also to have headroom) and mostly a multitude of that.
The easiest would be buying some active subs from reknown brands like SVS. But there are many diy designs out there that can be as good or better. And build more than one sub, so the room modes can be beaten by spreading them out in the room (Search Toole's multisub technique). Your sub won't play loud mostly, but should be able to go loud to catch peaks and avoid compression and distortion on the bass by the amp (running out of current) or speaker (playing against it's limit). Bass is was more sensitive to this and the other bands, and easier to overdrive and smoke amps/speakers.
To crossover the coax to the sub, use active crossovers, be it analog or dsp. Don't try to do this passive, it seldom works right.
If you want a sub with tube amps, that is a very expensive and hard to do thing. You need high power tube amps, that cost a lot to build/buy, and even more to maintain. You will also need quiet some technical skills or a fulltime engineer to do that. But sub with a class D amp is way more controlled and easier to do and you won't mess up the sound, because tubes only add distortion to sub, not a warm organic sound like higher up (also trough distortion, but the kind we like). A good sub needs at least a 100w (also to have headroom) and mostly a multitude of that.
The easiest would be buying some active subs from reknown brands like SVS. But there are many diy designs out there that can be as good or better. And build more than one sub, so the room modes can be beaten by spreading them out in the room (Search Toole's multisub technique). Your sub won't play loud mostly, but should be able to go loud to catch peaks and avoid compression and distortion on the bass by the amp (running out of current) or speaker (playing against it's limit). Bass is was more sensitive to this and the other bands, and easier to overdrive and smoke amps/speakers.
To crossover the coax to the sub, use active crossovers, be it analog or dsp. Don't try to do this passive, it seldom works right.
This may sound crazy, but I have done it (not using this sub) and it works. You want to connect to an amplifier (class D/plate amp?) using the speaker outputs using a 2-3k resistor if the amp has a volume control, or a 5-10k pot if it does not. This link shows a very cheap path that I have not followed but the driving arrangement is the same.
https://www.transcendentsound.com/bucket-sub.html
with further information on:
https://tubehifi.websitetoolbox.com/post/subwoofer-project-6426090
The first page cited in the second reference won't load directly, but it does load for me it I enter it directly in my browser.
I have followed this path with my Altec 605Bs in open baffles using a Crown XLS 1002 and 2 18" inexpensive pro woofers in large H-baffles. Getting down into the 35hz or so range makes a huge difference.
Hope this helps,
Skip
https://www.transcendentsound.com/bucket-sub.html
with further information on:
https://tubehifi.websitetoolbox.com/post/subwoofer-project-6426090
The first page cited in the second reference won't load directly, but it does load for me it I enter it directly in my browser.
I have followed this path with my Altec 605Bs in open baffles using a Crown XLS 1002 and 2 18" inexpensive pro woofers in large H-baffles. Getting down into the 35hz or so range makes a huge difference.
Hope this helps,
Skip
If you do that you'e stealnig watts from your tube amp, and your tube amp goes faster in distortion. You basicly use your tueb amp as preamp.
A power amp like that expect 4v (2w) input as max input signal, so not much is left for the top. You won't smoke your tube amp, but you will loose a lot of it's very limited power.
A power amp like that expect 4v (2w) input as max input signal, so not much is left for the top. You won't smoke your tube amp, but you will loose a lot of it's very limited power.
The only real right method is with a preamp feeding an active crossover that feeds the amplifiers, all the others create more issues than it solves.
Thank you, at the moment I have two integrated tube amps, so it looks like it is not possible for now to add subwoofers.
I'll see what I can do when I have a preamp and power amplifier. At that point, given that I will need an help for the low frequencies, I may consider an open baffle for the Altec driver. It has a Qts of 1.54.
I'll see what I can do when I have a preamp and power amplifier. At that point, given that I will need an help for the low frequencies, I may consider an open baffle for the Altec driver. It has a Qts of 1.54.
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On this JeLabs blog, the guy talks about an open baffle developed in Japan which suits this kind of 8" coaxial drivers:
https://jelabsarch.blogspot.com/2012/06/open-baffle.html
When I have preamp and power amplifier I may think about this open baffle with some help for the bass.
The cabinet I have now was developed during the early seventies by the italian Altec Lansing dealer. They called it Altec Cervino, it is a ported enclosure with an internal volume of 0.66 cubic feet. At the same time, the japanese Altec dealer developed a similar vented box with the Altec 409B which they called "DIG". Back then they didn't probably have T/S parameters, so I don't know how they tuned the box.
This 409 driver has got a big following in Japan. These owners have the driver in vented boxes same size as mine, I don't know why, given the T/S parameters.
http://alteclansingunofficial.nlenet.net/Thiele-Small.html
Mine had fiberglass only on the wall at the back and on top. There were resonances on the mid-high frequencies and the bass was a bit loose. I added a layer of Dacron on just one side wall and the resonances disappeared. Also the bass got tighter. I was lucky because I have no experience on building speakers.
So, for now it sound good. There's enough bass. The problem is the high sensitivity. It gets loud pretty quick and if you crank up the volume the bass can't follow. The sound gets flatter.
Thanks anyone.
https://jelabsarch.blogspot.com/2012/06/open-baffle.html
When I have preamp and power amplifier I may think about this open baffle with some help for the bass.
The cabinet I have now was developed during the early seventies by the italian Altec Lansing dealer. They called it Altec Cervino, it is a ported enclosure with an internal volume of 0.66 cubic feet. At the same time, the japanese Altec dealer developed a similar vented box with the Altec 409B which they called "DIG". Back then they didn't probably have T/S parameters, so I don't know how they tuned the box.
This 409 driver has got a big following in Japan. These owners have the driver in vented boxes same size as mine, I don't know why, given the T/S parameters.
http://alteclansingunofficial.nlenet.net/Thiele-Small.html
Mine had fiberglass only on the wall at the back and on top. There were resonances on the mid-high frequencies and the bass was a bit loose. I added a layer of Dacron on just one side wall and the resonances disappeared. Also the bass got tighter. I was lucky because I have no experience on building speakers.
So, for now it sound good. There's enough bass. The problem is the high sensitivity. It gets loud pretty quick and if you crank up the volume the bass can't follow. The sound gets flatter.
Thanks anyone.
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The subwoofer speaker level inputs would likely simply represent a very high impedance load for the amplifier. It's a bit like connecting a multimeter to a circuit to measure voltage. Inside the subwoofer is a voltage sensing circuit, which when added in parallel should insignificantly reduce the impedance seen by the amplifier. This contention is supported by the fact that the subwoofer has speaker output terminals, which would simply pass through the power to the left and right main speakers.
I doubt that the speaker-level output on the subwoofer can be adjusted. The raw signal fed from the amplifier would be present on those output terminals. The subwoofer's low-pass filter would need adjusting to ensure a reasonably good blending of the subwoofer's acoustic output with the low-frequency unfiltered acoustic output of the main speakers.
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I don't know what your source is, but i did not see a turntable so i guess it's all digital. Then maybe consider a MiniDSP flex as preamp. It will also do the xover and can help also to eq your system to your wishss. That has several digital formats in and one analog rca in, and 4 analog outputs to feed amps It has source selection, a volume control, absolute transparant dac's and advanced room eq trough the optional DIRAC system (if you wish that).
If you have that, you can use any powered sub with it, wihout having to think about how to filter it. THe miniDSP flex can do it transparant
If you have that, you can use any powered sub with it, wihout having to think about how to filter it. THe miniDSP flex can do it transparant
Thanks. So you think it is possible.
In fact, on this video, a guy measures with a multimiter the impedance of two bookshelf speakers, which is about 7 ohm. Then he powers on an active subwoofer and measures the speaker level input impedance, which is very, very high.
Then he connects with cables an amplifier's speakers terminals in parallel to the two bookshelf speakers and the active subwoofer's speaker level imputs. Then he powers on the subwoofer and measures on the cables an impedance of about 7 ohm, which is same as the two bookshelf speakers alone.
According to this video, it seems like this way the impedance read by the amplifier won't change much compared with the two speakers alone. But he was using a solid state amplifier.
Do you think it works this way also with a tube amp? From the amplifier speakers terminals, two cables to the speakers, two more in parallel to the speaker level imputs of the subwoofer. Then I adjust volume and filter frequency. All this without using the speaker outputs of the subwoofer.
Is that what you meant?
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I don't know what your source is, but i did not see a turntable so i guess it's all digital. Then maybe consider a MiniDSP flex as preamp. It will also do the xover and can help also to eq your system to your wishss. That has several digital formats in and one analog rca in, and 4 analog outputs to feed amps It has source selection, a volume control, absolute transparant dac's and advanced room eq trough the optional DIRAC system (if you wish that).
If you have that, you can use any powered sub with it, wihout having to think about how to filter it. THe miniDSP flex can do it transparant
The source is Amazon music unlimited, then to Fiio E10k type C usb DAC, then from usb dac to tube amp. Thanks for the tip, this is another option.
If you have that, you can use any powered sub with it, wihout having to think about how to filter it. THe miniDSP flex can do it transparant
The source is Amazon music unlimited, then to Fiio E10k type C usb DAC, then from usb dac to tube amp. Thanks for the tip, this is another option.
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These are not the right way to use this kind of equipment. He may get away with it, but in a lot of times your sub will sound distorted or drive hte impendance that the amp sees to low so it create a short a certain frequencies. Driving an amp with the output of another amp is a receipe for disaster, the impendance does not match and the output levels also not. Both cause extra distortion, in your main speakers and in the subs.
The only way to connect a sub without an extra amp is a passive crossover, but that will be (to do it right) way more expensive and tricky to do than use a active crossover and an extra amp fit for your sub. That is the reality. All those "tricks" that someone post on youtube are bogus. A speaker out signal is not ment to drive anything but a speaker.
A typical amp asks an imput signal between 2 and 4V in a high impendance (600ohm). Your speaker output signal is made to drive a speaker at low impendance, that signal is not fit to drive an amplifier, it's made to drive low impendance (2-16ohm) device with whatever your amp can provide of output.
I'll wait to have the right gear to add subwoofers. Either preamp and power amps with crossover or the miniDSP flex a member was talking about. Thanks.
I will study the possible options
I will study the possible options
The following is a diagram provided in the user manual for the Yamaha YST-SW45 subwoofer. I expect that Yamaha know how to properly and usefully connect their subwoofer to a hi-fi stereo speaker system.
The other option is to use the B speaker outputs for the cables that run to the subwoofer. This is also shown in the Yamaha user manual, as seen below.
This NOT what's happening here at all.
The high load impedance simply means that very little current, and little associated power, will be sent through the high-impedance part of the circuit. It all depends on how the circuit is designed to work, and Yamaha would be expected to get it right for the application at hand.