The painting process is finished, the cabinets are drying, tomorrow they are lowered (I am in the heights of the house) to the place of listening and the installation of the drivers and terminal panel of connection begins.
To weld and screw! This part will be a lot more fun than painting!
To weld and screw! This part will be a lot more fun than painting!
Attachments
Perhaps open holes in place of midwoofer and tweeter?
TBH, the DTQWT is a crazy design of Troels Gravesen and hard to understand. I wouldn't be surprised when it finally doesn't come up to expectations. At least the 18 mH coil in the woofer filter and the acoustic interaction of woofers and midwoofer give raise to doubts. But let's hope the best.
TBH, the DTQWT is a crazy design of Troels Gravesen and hard to understand. I wouldn't be surprised when it finally doesn't come up to expectations. At least the 18 mH coil in the woofer filter and the acoustic interaction of woofers and midwoofer give raise to doubts. But let's hope the best.
**To weld and screw! This part will be a lot more fun than painting!**
Well, this beautiful result makes up/compensates for every drop of sweat!
About bass, probably the DTQWT will make bass only with all three bass speakers in place and connected to amplifier/crossover (I don't know if you tested only with Eminences or with the 8008 too), and/or with the Eminences fully "burned up", since their suspension is hard when new. Some new builders complains with that.
But I don't surprise if the total bass SPL perceived is a little less than one bass reflex (even with Eminenced fully "cured"), since most bass reflex desings have a bass hump, and a large group delay and distortion, different from TQWT, and results in different bass timbre (I prefer the sound of TQWT, is more realist to acoustical bass instruments).
EDIT: I don't have the Eminences but in forums is common the suspension issue.
Well, this beautiful result makes up/compensates for every drop of sweat!
About bass, probably the DTQWT will make bass only with all three bass speakers in place and connected to amplifier/crossover (I don't know if you tested only with Eminences or with the 8008 too), and/or with the Eminences fully "burned up", since their suspension is hard when new. Some new builders complains with that.
But I don't surprise if the total bass SPL perceived is a little less than one bass reflex (even with Eminenced fully "cured"), since most bass reflex desings have a bass hump, and a large group delay and distortion, different from TQWT, and results in different bass timbre (I prefer the sound of TQWT, is more realist to acoustical bass instruments).
EDIT: I don't have the Eminences but in forums is common the suspension issue.
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Answer to Dizzi and DIYbras:
(This goes out like San Google, I have little time now and there will be a bug review on my part)
Ufffff, testing the rear speakers just was not a good idea. I figured it could somehow be low in the style of an OB, but this design works totally different.
Yes, the point was that without the front drivers the backwave of the speakers Eminence escaped on all sides but with strange turbulences, oblivious to the design expected.
The coil reinforces Troels as the lower octaves, I think.
But obviously everything is ready with the cabinet closed.
I finished one of the two boxes and tried it with recordings that I know well.
For this I used the amplifier SS, things will be much better with the valve, but the result is excellent!
As Diybras says, the basses are very ditintos to those of a bass reflex design. They are less bombastic, but have cleanliness, definition and speed. As always, it is very difficult to describe the sound in words. The middle range low, medium low and high is excellent, rich in details and the instruments and voices sound natural and rich in nuances, details have appeared, many details that give great wealth to the music in that range.
The integration achieved between JA8008 and TW034 is perfect.
In short, this promises much more when you finish the other box and feed the whole system with vacuum valves.
I did not hear in this preliminary test string instruments like a double bass in a jazz ensemble. That will be for the end, and with all the artillery in operation. But I know he will not disappoint me, when I consulted Troels about the seriousness of the DTQWTII, his response was "dry and fast." It is what I look for in that range, to feel the fingers of the performer when playing with the four strings, not a cloying mix of bass notes with absence of harmonicas.
I'll tell you more, thanks for your opinions !
(This goes out like San Google, I have little time now and there will be a bug review on my part)
Ufffff, testing the rear speakers just was not a good idea. I figured it could somehow be low in the style of an OB, but this design works totally different.
Yes, the point was that without the front drivers the backwave of the speakers Eminence escaped on all sides but with strange turbulences, oblivious to the design expected.
The coil reinforces Troels as the lower octaves, I think.
But obviously everything is ready with the cabinet closed.
I finished one of the two boxes and tried it with recordings that I know well.
For this I used the amplifier SS, things will be much better with the valve, but the result is excellent!
As Diybras says, the basses are very ditintos to those of a bass reflex design. They are less bombastic, but have cleanliness, definition and speed. As always, it is very difficult to describe the sound in words. The middle range low, medium low and high is excellent, rich in details and the instruments and voices sound natural and rich in nuances, details have appeared, many details that give great wealth to the music in that range.
The integration achieved between JA8008 and TW034 is perfect.
In short, this promises much more when you finish the other box and feed the whole system with vacuum valves.
I did not hear in this preliminary test string instruments like a double bass in a jazz ensemble. That will be for the end, and with all the artillery in operation. But I know he will not disappoint me, when I consulted Troels about the seriousness of the DTQWTII, his response was "dry and fast." It is what I look for in that range, to feel the fingers of the performer when playing with the four strings, not a cloying mix of bass notes with absence of harmonicas.
I'll tell you more, thanks for your opinions !
Attachments
Diybras:
The drivers were previously softened with sine tones of 40 hz with Audacity software. Although I am somewhat skeptical about it, I did not want to waste time waiting for a progressive and hypothetical improvement in sound, which may not be a real improvement by "softening" suspensions, but rather the discovery by our ears of new nuances over time, And becoming accustomed to the new general "timbre" of new development. There is an interesting link about it, I will look for it ...
The drivers were previously softened with sine tones of 40 hz with Audacity software. Although I am somewhat skeptical about it, I did not want to waste time waiting for a progressive and hypothetical improvement in sound, which may not be a real improvement by "softening" suspensions, but rather the discovery by our ears of new nuances over time, And becoming accustomed to the new general "timbre" of new development. There is an interesting link about it, I will look for it ...
Here is the link, it is worth reading even if it is something old, it has full force to my understanding and to know ....
Matrix-Hifi
Click on ( Can read the page in english )
If you want to know the truth, choose the red pill...
El rincón - The corner
Rodaje de altavoces - Speakers Burn In: What manufacturers say...
Good luck in your project! I am very happy to have been helpful. You will not regret. Today I auditioned jazz ..... there is good news, but today is late here and at midnight I want to see tennis, the Australian Open ..... my other passion !
Answer to Dizzi and DIYbras:
(This goes out like San Google, I have little time now and there will be a bug review on my part)
Ufffff, testing the rear speakers just was not a good idea. I figured it could somehow be low in the style of an OB, but this design works totally different.
Yes, the point was that without the front drivers the backwave of the speakers Eminence escaped on all sides but with strange turbulences, oblivious to the design expected.
The coil reinforces Troels as the lower octaves, I think.
But obviously everything is ready with the cabinet closed.
I finished one of the two boxes and tried it with recordings that I know well.
For this I used the amplifier SS, things will be much better with the valve, but the result is excellent!
As Diybras says, the basses are very ditintos to those of a bass reflex design. They are less bombastic, but have cleanliness, definition and speed. As always, it is very difficult to describe the sound in words. The middle range low, medium low and high is excellent, rich in details and the instruments and voices sound natural and rich in nuances, details have appeared, many details that give great wealth to the music in that range.
The integration achieved between JA8008 and TW034 is perfect.
In short, this promises much more when you finish the other box and feed the whole system with vacuum valves.
I did not hear in this preliminary test string instruments like a double bass in a jazz ensemble. That will be for the end, and with all the artillery in operation. But I know he will not disappoint me, when I consulted Troels about the seriousness of the DTQWTII, his response was "dry and fast." It is what I look for in that range, to feel the fingers of the performer when playing with the four strings, not a cloying mix of bass notes with absence of harmonicas.
I'll tell you more, thanks for your opinions !
Great looking speakers you have made! I built these 2 years ago, and experienced a lack of bass in the beginning. For me, it helped playing modern dance music with a parallelled gain clone for a couple of months. Now I'm back to tube and jazz bass sounds awesome=) It's a lot of fun how different amplifiers change how the speakers are percieved. With gain clones, they are almost scary=)
Madisound says that factory burn-in don't exists. I believe that. Unless is a very expensive HiEnd model (hmmmm)...Here is the link, it is worth reading even if it is something old, it has full force to my understanding and to know ....
Matrix-Hifi
Click on ( Can read the page in english )
If you want to know the truth, choose the red pill...
El rincón - The corner
Rodaje de altavoces - Speakers Burn In: What manufacturers say...
So, for the Eminences, some owners listen the suspension making "crack sounds", when displace the cone by hand. Probably the sound from spider.
If this is true, a large time is needed, or instead use brute force (using near Xmax and lower than fs burn-in signals, or even pushing by hand).
TS parameter do change with time, including fs. Some speakers even change the border resonance amplitude with time.
PS.: good site indication! This website I've read some years ago, and is good to read sometimes/remember to ponder about audio excesses...
Thank you for your comment, I am happy that you find it to your liking .
I agree that the sound changes a lot with different amplifiers, especially from solid state to vacuum tubes.
To my ears "there is something else" with valves, transparency, harmonics, etc.
There is a problem in my way of seeing with the bass.
Solid state delivers solid, but dirtier ones. I love the bass tubes, soft, clean, less impactful, maybe, but I do not listen to rock music anymore.
I do not see need to soften in my DtqwtII, I already said that they have been pre-paved but to not have to wait any time to "improve" the sound.
Charlie Haden, Rostropovich, Nuda Music, etc., etc. I have been confirmed that the bass are wonderful!
: good site indication! This website I've read some years ago, and is good to read sometimes/remember to ponder about audio excesses...
I'm glad to bring to your mind old readings about voodoo audio!
I agree with the final opinion of Matrix HI FI. If mechanically the suspension loosens quickly, we are in trouble because it will continue fast to its zone of destruction and distance of its parameters. What is the stop point ?
Well, the first models of my vintage JBL brought a suspension of yellow treated fabric (Lans a loy) which many people recommended to deal with brake fluid .... there were times of measurements with software and TS did not exist ..
Apart from this, let me tell you something:
Many times people want to hear the sound of their dreams in an acoustic cabinet without giving themselves time to wait for the musical passages where there is good information.
Bad bafles do that, they continuously make sounds that are not real, but they catch on a first listen, They will also tire in an hour of hearing .....
I remember the typical baffles that accompanied the Japanese systems of the seventies. (Sansui, Pioneer, Akai, Tecnnics, etc.) Nothing worthwhile, only a few models had something to say. I think the exception of the Japanese speakers were the Yamaha, and it's no coincidence, they also made musical instruments ...... even pianos!
I sold audio in several specialized houses. For very few customers with trained ears, the cabinets of those complete systems were replaced by AR, JBL, Infinity (their first models, not the last ones) Altec Lansing, etc.
As you can see, most US cabinets were imported here.
Something from England, Celestine, Tannoy (the loose and flat speakers to set the box), Kef ..
I also had the opportunity to hear from Europe Tandberg, Phillips, Grundig (these were too bright if compared to the American or Japanese speakers, I think this was because DIN standards were very much taken into account, and European recordings also They obeyed
I never heard a Bose! But yes Koss (yes, the brand of the headphones, were not bad, but they also did not stand out) the monster Adase of Phase Linear, the line ESS, In PA Electro Voice and JBL were the ones that sent here.
In home speakers, the revelation of those years was the DCM Time Windows. Breathless sound came out of those small columns, they had Phillips speakers, but they needed a lot of power to look, 200 watts RMS up.
Anyway, I had many experiences to evaluate this DTQWTII.
Ear training calls it, even if we do not have auditory memory, we know what we are looking for.
DTQWTII is a great speaker, natural sound, good dynamics, details, etc. The sound comes out of the boxes but it does not stay locked, it floats in the air. As it should be.
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Correction : Celestion
Celestion Ditton 44 Series II woofer information needed! | Audiokarma Home Audio Stereo Discussion Forums
Correction : Andrómeda of Phase Linear
RC: Bob... ER, I mean... Mr. Carver...Is that you? (Page 1 of 2)
These are :
http://www.diyaudio.com/forums/multi-way/50200-dcm-time-window-rebuild-6.html
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I forgot to upload the photos of the installation of the front panel drivers and the binding posts.
These cables are good quality but very hard and difficult to peel! Then, it is essential that they do not put pressure on the connection terminals, could break with the manipulation. You have to fix them first. Then mold them by hand to bring them to their correct position and finally solder! Do not do it the other way around!
As you can see, I have not had much confidence in the gadget that came with the kit to fix the tweeters cables.
The glue of double tapes does not usually be as durable and would be a complication if it were detached in the future. So I have prepared this accessory with leftovers from the wax coils. Copper is a non-magnetic metal, better then, given the proximity to the ceramic magnet of the speaker. This is voodu audio?
Another point was the boards I had prepared for these drivers. I only used one of them to supplement one of the tweeters, which was somewhat sunken in its housing. it's not important anyway, just a detail of manic perfectionist ....
These cables are good quality but very hard and difficult to peel! Then, it is essential that they do not put pressure on the connection terminals, could break with the manipulation. You have to fix them first. Then mold them by hand to bring them to their correct position and finally solder! Do not do it the other way around!
As you can see, I have not had much confidence in the gadget that came with the kit to fix the tweeters cables.
The glue of double tapes does not usually be as durable and would be a complication if it were detached in the future. So I have prepared this accessory with leftovers from the wax coils. Copper is a non-magnetic metal, better then, given the proximity to the ceramic magnet of the speaker. This is voodu audio?
Another point was the boards I had prepared for these drivers. I only used one of them to supplement one of the tweeters, which was somewhat sunken in its housing. it's not important anyway, just a detail of manic perfectionist ....
Attachments
Basically my experience dictates that the speakers investment is clearly the correct and where most money proportionally needs to be spended, since no two speakers sound the same, and even two of same will sound very distinct in different ambients. I agree about good speakers being good speakers, so I not hesitate in recommending good "sober" sounding speakers to people, hence my recommendations about (D)TQWT (expensive but far better than throwing money in certain cables), and some others.
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Is good to suspend the tweeter wire since the terminals are very fragile. Even with something not 100% secure, since even so most mechanical force will be directed to it. Of course is only problematic during the construction phase. I don't used this in mine.I forgot to upload the photos of the installation of the front panel drivers and the binding posts.
These cables are good quality but very hard and difficult to peel! Then, it is essential that they do not put pressure on the connection terminals, could break with the manipulation. You have to fix them first. Then mold them by hand to bring them to their correct position and finally solder! Do not do it the other way around!
As you can see, I have not had much confidence in the gadget that came with the kit to fix the tweeters cables.
The glue of double tapes does not usually be as durable and would be a complication if it were detached in the future. So I have prepared this accessory with leftovers from the wax coils. Copper is a non-magnetic metal, better then, given the proximity to the ceramic magnet of the speaker. This is voodu audio?
Another point was the boards I had prepared for these drivers. I only used one of them to supplement one of the tweeters, which was somewhat sunken in its housing. it's not important anyway, just a detail of manic perfectionist ....
Transcribes Troels's description of the impedance of the DTQWT III, in the case of using two 10-inch speakers to have a total impedance of the system in 6 ohms. Obviously, this is applicable to DTqwtII.
The DTQWT-mkIII now features as standard a single 12" Eminence DeltaLite mkII driver as most people, based on feedback, do not use flea-powered tube amps, rather solid state - or higher powered push-pull valve amps not having any trouble running a minimum 4 Ohms impedance. Those wanting a higher impedance (6 Ohms) can obviously still use two 10" bass drivers coupled in series as was standard the DTQWT mkII. Go to DTQWT mkII page for cabinet details and bass section crossover.
DTQWT-mkIII
I decided to measure the impedance (resistance actually, as we know the impedance is always greater because it is a value that is usually measured at 1000 hz, (there are exceptions to this, some twofers measure them at 400 hz and some tweeters at 4000 hz) And it varies constantly according to the signal applied. Basically, the inductance starts playing and in very small proportion the capacitance.
But I do not intend to go over here concepts of Ohm's Law on how inductive reactance or capacitive reactance is calculated, or the combination of both with resistance, etc.)
I just wanted to check the load that the amplifier sees to select the correct connection with the output transformer of my valvular amplifier.
So we have the following measurements.
10.5 ohms for the bass sector,
6.5 ohms for bass, mid and treble
Applying Ohm's Law for resistors of different value in parallel, we have 4.014 Ohms.
My amplifier has (as is standart) two secondary windings, 4 and 8 ohms ....
I have used both connections and for my ears, I have not noticed any differences.
But we know that the best energy transfer is achieved when the impedance matching is optimal, thus obtaining 50% of the energy present in the primary. The rest is lost in the form of heat and other phenomena, I imagine.
In short, which connection would they use? Am I reasoning correctly or is something missing ?
The pen is a special gift I received from Iwona. Only for me. Please do not insist if you order from Jantzen Audio.
The DTQWT-mkIII now features as standard a single 12" Eminence DeltaLite mkII driver as most people, based on feedback, do not use flea-powered tube amps, rather solid state - or higher powered push-pull valve amps not having any trouble running a minimum 4 Ohms impedance. Those wanting a higher impedance (6 Ohms) can obviously still use two 10" bass drivers coupled in series as was standard the DTQWT mkII. Go to DTQWT mkII page for cabinet details and bass section crossover.
DTQWT-mkIII
I decided to measure the impedance (resistance actually, as we know the impedance is always greater because it is a value that is usually measured at 1000 hz, (there are exceptions to this, some twofers measure them at 400 hz and some tweeters at 4000 hz) And it varies constantly according to the signal applied. Basically, the inductance starts playing and in very small proportion the capacitance.
But I do not intend to go over here concepts of Ohm's Law on how inductive reactance or capacitive reactance is calculated, or the combination of both with resistance, etc.)
I just wanted to check the load that the amplifier sees to select the correct connection with the output transformer of my valvular amplifier.
So we have the following measurements.
10.5 ohms for the bass sector,
6.5 ohms for bass, mid and treble
Applying Ohm's Law for resistors of different value in parallel, we have 4.014 Ohms.
My amplifier has (as is standart) two secondary windings, 4 and 8 ohms ....
I have used both connections and for my ears, I have not noticed any differences.
But we know that the best energy transfer is achieved when the impedance matching is optimal, thus obtaining 50% of the energy present in the primary. The rest is lost in the form of heat and other phenomena, I imagine.
In short, which connection would they use? Am I reasoning correctly or is something missing ?
The pen is a special gift I received from Iwona. Only for me. Please do not insist if you order from Jantzen Audio.
