well, i built a pair of troels gravesen tjl3w's 3 years ago, and i have to say that i always felt they had a amazing sound apart from 2 aspects-
1) there was a conjestion to the upper mid that ment that rock music and generally complicated music lost instrument separation. i spent years trying to get to the bottom of this. was it the fact that they are 4th order? was it because they had too many components in the signal path? did i build the crossovers wrong? were there resonances in the box? i tried different sources and changed my amplifier to no avail.
a couple of months ago, i bought a sure electronics t2050 amp and power supply and found it changed the sound alot- for the better. that night i listened all night, like i have never before -simply amazed. i never went to sleep and just went to work with a grin on my face.
during that night i decided to play with the speaker positions- and whatever i was still missing returned. the sound was every bit as acomplished as the best i have ever heard.
over the years i had doubted troels abilities because the speaker i had built didnt perform (or so i thought), so i never built any other designs because i had lost faith in diy speakers. becaouse of this i bought and sold approximatly 50 commertial speakers that are well respected designs- only to find that they didnt perform that well at all either in fact none even came close to the tjl3w's(a couple were reasonable).
now im left with a couple of the best ive run into over the last 3 years, and the tjl3w's are sold because of the fact that they simply dont go loud enough for my 300m3 living room as a L+R in my rather serious surround setup.
i will likely build a pair of dtqwt's or geddes abbys as keepers that fit my application. as i havent heard the dtqwt's but i have no doubt they perform. but i have heard the geddes units and i was impressed enough- but i will admit that they dont seem to dissapear like the tjl3w's did, but then no horn tweeter ever did for me, and i can accept the trade off for what i get in return.
as the OP is in england, you will find my tjl3w's on demo at the next hifiwigwam show if your interested. feel free to pm me.
1) there was a conjestion to the upper mid that ment that rock music and generally complicated music lost instrument separation. i spent years trying to get to the bottom of this. was it the fact that they are 4th order? was it because they had too many components in the signal path? did i build the crossovers wrong? were there resonances in the box? i tried different sources and changed my amplifier to no avail.
a couple of months ago, i bought a sure electronics t2050 amp and power supply and found it changed the sound alot- for the better. that night i listened all night, like i have never before -simply amazed. i never went to sleep and just went to work with a grin on my face.
during that night i decided to play with the speaker positions- and whatever i was still missing returned. the sound was every bit as acomplished as the best i have ever heard.
over the years i had doubted troels abilities because the speaker i had built didnt perform (or so i thought), so i never built any other designs because i had lost faith in diy speakers. becaouse of this i bought and sold approximatly 50 commertial speakers that are well respected designs- only to find that they didnt perform that well at all either in fact none even came close to the tjl3w's(a couple were reasonable).
now im left with a couple of the best ive run into over the last 3 years, and the tjl3w's are sold because of the fact that they simply dont go loud enough for my 300m3 living room as a L+R in my rather serious surround setup.
i will likely build a pair of dtqwt's or geddes abbys as keepers that fit my application. as i havent heard the dtqwt's but i have no doubt they perform. but i have heard the geddes units and i was impressed enough- but i will admit that they dont seem to dissapear like the tjl3w's did, but then no horn tweeter ever did for me, and i can accept the trade off for what i get in return.
as the OP is in england, you will find my tjl3w's on demo at the next hifiwigwam show if your interested. feel free to pm me.
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If you have 300m3 to fill with the sound, I would go with the DTQWT-Extended with two 12"" bass drivers.
DTQWT-ha ha... monsterous!!!
the dtqwt will be fine, and frankly is already pushing the limits with the WAF. my 2 18" jbl subs handle the lows so i dont need further reinforcement in that area
i must have missed that added design or it must have been added in the last 20 hours (i check the site every day for updates) hes working on a 1st order crossover at the mo
the dtqwt will be fine, and frankly is already pushing the limits with the WAF. my 2 18" jbl subs handle the lows so i dont need further reinforcement in that area
i must have missed that added design or it must have been added in the last 20 hours (i check the site every day for updates) hes working on a 1st order crossover at the mo
300m3- its the volume of the room not the floor area.
high ceilings, so not that big. as for expensive house... i live i bath, so i was screwed from the start.Looked on WigWam briefly but found no reference to the next show. Is it still in Chester/Scalford? It's a bit far for me!
Earl Geddes research is very good. It's a shame his threads on here get so much flak from some other self-espousing experts. At least he's published his research to acclaim from peers.
Can you run the Sure Electronics T2050 at high volume? I ask as when at <60Wrms it's very efficient with vanishingly low distortion, but after that THD rises very sharply and is higher than would normally be accepted in an audiofile product. But then again, as Earl Geddes' research points out, THD is not a congruent concept with human hearing perception and how people perceive distortion is not best reflected through THD figures. IOW, if the distortion in the T2050 is similar to a SET setup, then high THD will not be perceived. At $50 USD it looks like a bargain. Certainly doesn't sound like it's going to be mediocre if you are prepared to demo it at a WigWam show - some of the "wammers" have some very nice commercial setups!
300m3- its the volume of the room not the floor area.
Oops.. my bad! What's wrong with Bath? Too near the Bristol Show??
Just saw your thread on the Wam and everybody has recommended monstrously huge speakers - so much for WAF!
I think your looking in the right area. Serge's recommendation was quite good. You've done the research as the Geddes avoid typical horn colouration he speaks of. Other than that, he's right, TLs and reflex designs only!... So you've arrived looking at the DTQWT / DTQWT Extended!!!
How does the T2050 compare to the Parasound?
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bath is the second most expensive place to live in england. a small 1 bed flat in town is about 800gbp per month rent. im just lucky i have so many limbs considering how much my place costs me!
the 2050 is indeed power limited, but as long as your not going to rock the house down, its rather impressively coherant (took some running in though). my previous amp was a parasound halo a21 and a a51 running tri amped into the tjl3w's, thats 750wrms @ 8 ohms each speaker,and not a cheap option, so im aware of what i get with more power.
on paper 60w rms isnt enough for a 85db/w speaker, but if were looking at amplifier clipping, on lossless surround, with its massive dynamic peaks 750w isnt nesasarily enough either. a amplifiers ability to recover from clipping and how it clips suddenly seams more important in light of this.
i dont know if anyone has investigated tripaths performance in this area, but it may be a factor, along with the anomalie that SET amps dont sound destorted untill very high levels to my ears. so maby this is possible for t class?? -no idea
one realy good thing about all this is that the only shortcomings of the tjl3w running with the sure amp was it sounded a little dynamically limited when you turned up the wick, not badly- but it could be better in this area.
however running a pair of focal 1037be's showed that the effect is vastly reduced with a more efficiant speaker (as it should be!)-all be it a rather bright speaker.
in my experience, running a 95db/w speaker is very revealing of the partnering electronics, so the dtqwt will show what the amps made of and its got the wonderfull atribute of very low dynamic compression, so knowing troels taste of very neutral voicing combined with these factors will be interesting!
one small note, i happen to use the tweeter used in the dtqwt in one of my own speakers that ive picked up along the way, and it is indeed special. its a interesting one as its kind of got that 'live' sound to it, sort of the sound of a real drum kit vs most other kit sounding a bit dull- realy good for impact. (hence it kind of supports me building the dtqwt.)
i dont come over here that much, im surprised geddes gets a bashing, i know several diyers who have built the respected linkwitz orions and sold them having heard the geddes.
the wam show was a couple of months back, so youve got around 10 months to go bud. i will say that it makes the bristols show look like a joke, and that the experience is worth thousands of hours on any forum. nice bunch too!
if you do manage to build the dtqwt, id give anything to have a listen!- current funds are going on a new tripath amp -connex electronic t3020v3c, 200w rms at 8 ohms each channel, bi-amped for each speaker in a 5 channel surround setup- so monoblock setup. can be bridged to 1000wrms at 4 ohm. sounds like alot of power, but 1000w is only 12db louder than 60w.
the 2050 is indeed power limited, but as long as your not going to rock the house down, its rather impressively coherant (took some running in though). my previous amp was a parasound halo a21 and a a51 running tri amped into the tjl3w's, thats 750wrms @ 8 ohms each speaker,and not a cheap option, so im aware of what i get with more power.
on paper 60w rms isnt enough for a 85db/w speaker, but if were looking at amplifier clipping, on lossless surround, with its massive dynamic peaks 750w isnt nesasarily enough either. a amplifiers ability to recover from clipping and how it clips suddenly seams more important in light of this.
i dont know if anyone has investigated tripaths performance in this area, but it may be a factor, along with the anomalie that SET amps dont sound destorted untill very high levels to my ears. so maby this is possible for t class?? -no idea
one realy good thing about all this is that the only shortcomings of the tjl3w running with the sure amp was it sounded a little dynamically limited when you turned up the wick, not badly- but it could be better in this area.
however running a pair of focal 1037be's showed that the effect is vastly reduced with a more efficiant speaker (as it should be!)-all be it a rather bright speaker.
in my experience, running a 95db/w speaker is very revealing of the partnering electronics, so the dtqwt will show what the amps made of and its got the wonderfull atribute of very low dynamic compression, so knowing troels taste of very neutral voicing combined with these factors will be interesting!
one small note, i happen to use the tweeter used in the dtqwt in one of my own speakers that ive picked up along the way, and it is indeed special. its a interesting one as its kind of got that 'live' sound to it, sort of the sound of a real drum kit vs most other kit sounding a bit dull- realy good for impact. (hence it kind of supports me building the dtqwt.)
i dont come over here that much, im surprised geddes gets a bashing, i know several diyers who have built the respected linkwitz orions and sold them having heard the geddes.
the wam show was a couple of months back, so youve got around 10 months to go bud. i will say that it makes the bristols show look like a joke, and that the experience is worth thousands of hours on any forum. nice bunch too!
if you do manage to build the dtqwt, id give anything to have a listen!- current funds are going on a new tripath amp -connex electronic t3020v3c, 200w rms at 8 ohms each channel, bi-amped for each speaker in a 5 channel surround setup- so monoblock setup. can be bridged to 1000wrms at 4 ohm. sounds like alot of power, but 1000w is only 12db louder than 60w.
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Wow, I have been busy and not checked the forums for 2 days. I see there has been a lot of activity recently. I'm glad to see we have a strong UK contingency here.
m12ax7, you make a very good point. To answer your question, yes I am currently reconsidering my entire system. This entire project started because I moved recently.
I have a dedicated home theater room. I have a 7.2 surround set up. My mains are paradigm studio 60s, studio center, and 4 studio dipole surrounds. I have 2 paradigm pw-2200 subwoofers, which are 12 inch ported designs. These are paired with a 1080p projector and 120 inch screen. My receiver is an integra dtr 8.9, which is rated at 145 watts per channel. I realize that with all channels driven, the output will be lower. I went with a receiver due to funding constraints. I have had my speakers for 5-9 years.
Anyway, when I set the system up in the new house it sounded bad. The bass response was awful. Now I realize that room acoustics, plays a huge role here. But basically, I started researching and caught the bug to redo my system. My gear will be going up for sale as I replace individual pieces.
I started with building a sub enclosure. I am brand new to DIY and went to parts express and decided to go with 2 titanic MK-III 15" subs. I realize now I could have done better, but it was a learning experience. I built dual ported enclosures, in a single console table. I finished it in cherry, with bun feet, and used a finishing technique to get a mirror finish. Overall, I am happy with the look. It sits beneath my movie screen and my center channel is located on top. I enjoy the woodworking portion of DIY very much. Any piece of equipment I build, I would like to look unique or well finished.
If you check my previous posts, you will see that I have purchased 60 board feet of African Ribbon Striped Sapele to build the external panels of my cabinets. I am interested in trying a finishing technique used for guitars and musical instruments. If I am going to build a large floor standing 3 way design, I don't want them to be an eye sore.
Let me be clear on madisound's recommendation. I hate to pass misinformation on a forum. I called as a beginner who was having trouble transferring designs on a website to real world performance. The operator who I spoke with, told me that the ZRTs would have a more refined sound than the SB12.3. My recollection is that he recommended the ZRT 2 way design because he felt that a 2 way design would be more accurate than a 3 way. Now it's tough for anyone to take a phone call and interpret someone else's preferences. So I think he gave me his honest opinion.
I intend to build my own cabinets. As for 2 vs 2.5, sealed or ported, I think you would have to look at your intended use and output level. For me, the 2 way paired with a sub-woofer would be less expensive and have a stronger low end.
I am pretty set on the Troel's design. I had not seen the link to the DTQWT extended. I will read it once I finish this post. My wife took one look at the 12.3 and was not happy. After 11 years of marriage, I have learned to choose my battles.
As for amplification, I am looking at several options. I would love to get into separates. I have looked for years at the anthem processor, but at $7000 I refuse to pay that on principal. Hence why I chose the receiver for the processor section which is very well regarded for its video processing. I have thought about purchasing amplifiers and using the receiver as a pre-amp processor.
I am considering for solid state, the emotiva line. Class A/B with an excess of power. They also have a processor for $700 which is getting a lot of attention. I am also looking at Troel's suggestions of the Jungson JA-88D(09), Class A 80wx2. I can only find it in Hong Kong, with 230v input. I'm not sure if it would work it in the US with a step up converter. There is a US distributor but he is asking $2300 vs $750 online.
I am debating the jump into tubes. I had the crazy I idea of buying 2 of these amps and bi-amping the DTQWTs.
YAQIN MC-100B PushPull Stereo Integrated Tube Amplifier - eBay (item 130383341318 end time May-14-10 20:42:26 PDT)
What do you guys think?
All the drivers are available in the US from parts express and madisound. However, I spent a night researching and the kit price is much better. Infinitegain, verified this in Europe as well.
The total I reached was roughly $1200 for the SB12.3 and $1700 for the DTQWT before the cabinets are built. I have spent about $500 on the lumber already.
Please include a link to the Elsinore. Sorry for the long post, hopefully I answered your questions.
My Greenwich flat is my second home and is £1000pcm for a two-double bedroom affair, but then I did luck out finding the place.
I used to have Chord Electronics amps (a little glassy/bright and 2D, but amazingly detailed, fast and resolving). These were good with my Wilson Benesch speakers... but I demoed the ultra high power KW500 from Musical Fidelity (scoffed at on the Wam these days as MF marketing is foo) and it actually did everything the twice as expensive Chord pre/power did, but didn't run out of steam on musical transients. I suspect it's because as Earl Geddes researched, even a 12Wrms piece of music may have very brief transients that demand up to 800W. I don't like MFs marketing either, or the endless revamping products, but in this case the KW500 and KW550 or superchargers are very good.
Exactly... and a proven fact often denied.
Yep.
Douglas Self did research to show it was possible to engineer a SS amp to create it's distortion in line with a SET and consequently sound like a SET. Few manufacturers have utilized this as it increases product cost. However, I have a gut feeling that hybrid amps using miniature tubes in the output stage of an active pre-amp can shift harmonic distortions to be more tube like. I would love to see some research in this area because I have discovered I prefer hybrid amps to all SS, and high power over low power so long as THD+N is <0.5%. I think it is possible your T2050 is designed well-enough to keep any harmonic or clipping distortions from sounding awful - maybe a soft clipping design is used?
1037Be bright? I thought exactly that when I was at the 2009 Bristol Show where it was used by Arcam (traditionally thought of as warmer than neutral). I love it's detail though and many other JM Lab/Focals.
This is exactly why I am interested in this speaker, or finding an equally efficient but not-too-wide open-baffle design. I am hoping (long-term) to build the Vacuum State RTP3D preamp on the kit (from VS themselves) or DIY basis (self-sourced parts) and do my best to research and clone the matching DPA300B. This should give me PP tube power and bass with infamous 300B midrange, good linearity and less perceived distortion than solid state typically allows. Couple this with a very efficient 'live' sounding speaker and it should end 'upgraditis'.
I have to admit, it looked surprisingly cheap and ubiquitous at first glance. However, I accept that ultimately it is how the driver measures in an enclosure in the final analysis. It's good to know that some DIYers around here have used parts of the kit to good effect. I know the Eminence drivers are well respected in TL and open-baffle circles. The JA8008 is the wildcard, but improves on a good SEAS design and I couldn't find a capable substitute for it.
I stay away from the WigWam as it's highly polarised between militant-attitude objectivists and head-in-sand subjectivists. I fit neither camp. Earls research in to distortion perception shows that poorer THD measuring tube amps, in particular SETs, are *perceived* to produce a cleaner less distorted sound. I'm frankly tired of measurement-only objectivists bashing people trusting their ears as delusional.
To Earl's credit he sticks at it, defending his research and trying to correct people who are clearly arguing based solely on their experience and not necessarily proven research.
Well if I manage to build them I'll send you an invite. Unfortunately, the budget just got blown on a new Intel i7 3D graphics workstation for my wife's computer programming and games design degree. So I am back to coveting other people making headway on their DTQWT projects!
The Audioromy's have a good rep for sound. These use massive 813 tubes (the FU-13 model anyway). I understand that support for DOA or problems isn't that good, but that the working amps are amazing. There are plenty on this site who have Audioromy tube amps from eBay, or obtained the schematic and built one. Looking at the power in class A, it's easy to see why people go for them.
Here's the cheaper variety on eBay:
AUDIOROMY FU29 x2 Vacuum Tube Integrated Amplifier Hifi - eBay (item 270563451303 end time Apr-17-10 23:02:50 PDT)
Maybe see if you can find schematics and self-build?... I haven't looked, but they may be very good for a low cost design and you'll have something to consider about tubes in general going forward. *Make sure you research all the safety necessities for working with valves, high voltage and DC first*
It's funny you mention Audioromy, I was also considering the FU13. I'm trying to go with quality over quantity. I really don't know anything about tubes. I spent last week reading on a lot of forums. It seems for every amp out there, there are a number of tweaks to be made. People swapping tubes, caps, etc.
The scary part for me is that I also read about DOA equipment, rebadged tubes, or used tubes sold as new. It seems that reliable sources are hard to find. What would you recommend for a beginner? I can't help but feel I'll need a lot of power. I do listen at very loud levels. I will say that now that my new sub is complete, I'm seeing serious deficiencies in my mains. I had my first listening session with the new sub and I kept hearing a cabinet resonance. I thought it was the sub, but it was dead silent. It was the mains. I adjusted the crossover point to 80hz and it helped a lot but you could feel the cabinet vibrating. I can't wait to start on the DTQWT.
The DTQWT should be easy to bi-amp correct?
What do you think about the DTQWT extended? Those cabinets are enormous! I wonder if the wife will let them pass. What do you think the improvement will be? I have the extra material to build.
By the way you mentioned an amp and preamp you are considering building. Can you please post a link?
If you develop them with terminals suitable for bi-amping then yes. You have two crossovers and each can be hooked up to a pair of speaker terminals to be driven by an amp - one for bass, one for midrange and tweeter.
How big is your room and what are it's dimensions?
There is a very hi end preamp by Vacuum State called the RTP3D. Here's a retail one for sale (you need to scroll down) which on the same page has the matching monoblock pair - the DPA300B:
Vacuum State
Here's Vacuum State's website with a schematic of the previous version, the RTP3C:
Schematics
Vacuum State sell kit versions of their products. They also sell a cookbook with schematics of modular parts of their amps with explanations of the accepted electronic theory and the theory as to why their design is better than others, or more suited to a particular use. For the RTP3D, they sell a CD with schematics, bill of materials, technical training on the preamp and lots of photos to help build one, all for 100 Euros (the info, not the kit). I cannot afford the kit, I'll source parts myself.
It's an advanced design preamp, not typically suited to beginners. That does not mean it cannot be done, because it can. I've never built a tube preamp yet and so I am in the same predicament as you. However, you could possibly build this as a first tube amp like this guy did:
The Vacuum State Electronics Realtime preamplifier
Building the Vacuum State Electronics Realtime Preamplifier
There is a thread on DIY audio about being a beginner in tube amp builds. Somebody wanted to get the safety information together, which makes good sense. My father is a retired electronics engineer (RADAR and guidance systems with Royal Navy and Raytheon) and I'm in the fortunate that I can, if need be, call on him for help as he's been teaching his stuff to engineers around the globe for over 20 years, after just as long in navy service.
However, I cannot pester my dad. He knows so much that I'll never wrap my head around all he would say. I, like most, have to rely on books and sources of information. For building tube amps, Morgan Jones' "Building Valve Amplifiers" (ISBN 978-0750656955) focuses more on safety, wiring and fault finding techniques etc, and doesn't focus on design or anything. It really is aimed at developing a base from which to get basic competence in working with tube circuits in place. I'm going down this route too, so I will also rely on others on here. I come from the low-voltage computer builds, basic solid-state circuits and stuff, very little that is that dangerous - UNLIKE tube circuits.
To get you aware of the dangers and safety precautions, I'd follow (am following) this thread:
http://www.diyaudio.com/forums/tubes-valves/30172-safety-practices-general-ultra-high-voltage.html
The only reason I will attempt to build such a tube build is:
a) somebody who was also a tube-build noob, who I can also contact here in UK, has done it before me
b) all the information is available after purchasing a 100 Euro CD from Vacuum State
c) I have a retired electronic engineer father to help me understand anything I don't 'get' when reading either books or schematics.
Right, just re-read and noted I didn't say how to build the DPA300B's. Well, it's been discussed here at DIY Audio with a few links to the outlining theory and modules in the design. There are a few members who 'know' what is effectively on the inside but they couldn't draw/post a schematic because of commercial confidentiality on this model. However, enough is available to get the basic idea and design something effectively the same. I don't think the design is that far from the Audio Mirror's Troels uses. Most of the rest is in the Vacuum State purchasable information.
Hint link:
http://www.diyaudio.com/forums/tubes-valves/146923-300b-dpa.html
I've heard the RTP3C (the RTP3D got a new raw power supply and new matched FETs or BJT in the front of the RIAA circuit).
I can highly recommend the CD for the RTP3C/D build. Very well made, complete with schematics, parts lists and how to hard wire the amp even a novice can make this preamp.) But I found a few bugs in the linestage that I'd report to Allen.
I've can also recommend the PP1CS poweramp that can be upgraded to DPA300B but be aware of different filament voltages for those two amps.
Both the RTP3C/D and the DPA300B clone will be my finale tube amps in this life (and I'm only 41!) as they are so great that I don't have to hunt better designs. ;-)
And now I like to hear the DTQWT design of Troels Gravesen here in Denmark.
Will the DTQWT be better than my Emerald Physics CS2 Clones?
I can highly recommend the CD for the RTP3C/D build. Very well made, complete with schematics, parts lists and how to hard wire the amp even a novice can make this preamp.) But I found a few bugs in the linestage that I'd report to Allen.
I've can also recommend the PP1CS poweramp that can be upgraded to DPA300B but be aware of different filament voltages for those two amps.
Both the RTP3C/D and the DPA300B clone will be my finale tube amps in this life (and I'm only 41!) as they are so great that I don't have to hunt better designs. ;-)
And now I like to hear the DTQWT design of Troels Gravesen here in Denmark.
Will the DTQWT be better than my Emerald Physics CS2 Clones?
Hi Nelson,
Yes, I think I saw your name on DecWare where you built these. The CD with the info has to be the best kept non-secret in audio - you don't have to spend millionaire money!
Have you heard any of Troels other speakers? Like you, my thinking is the VS amps should be the last amps I own when couple with a suitably efficient speaker.
Yes, I think I saw your name on DecWare where you built these. The CD with the info has to be the best kept non-secret in audio - you don't have to spend millionaire money!
Have you heard any of Troels other speakers? Like you, my thinking is the VS amps should be the last amps I own when couple with a suitably efficient speaker.
I haven't heard any of Troels Gravesens speakers yet. But Troels seems to be an experienced speaker builder.
The Decware ZOB is a great speaker if you don't have massive bass requirements. But I'm used to deep, fast and massive bass from my CS2 clones so I'll build the HDT and try the broadcast system described by Steve. Beware that the ZOB/HDT is just for fun and I don't expect this system to take the price over my CS2s (next week they will be upgraded to CS2.3 clone status
)My RTP3C/D build only use Allens linestage design (and the RIAA in the future). The power supply is my own design using hybrid rectifier for the high voltage (tube and solid state as described at Lundahl Transformers, audio transformer and tube amplifier transformer manufacturer).
Furthermore the PSU is choke loaded into 15H R-filtered to another 15H (both Lundahl) and the shunt regulators are discrete designs of Manfred Huber (maybe you remember the motor control unit for the Teres turntable?). Nothing but ground floor noise is showing up on my FFT analyzer... 300 Volt and pumping more than 100mA pr. channel.
Last but not least I use Pickering low cap relays throughout instead of ELMA-switches. Audio signals are hardwired to the relays and control and voltages for the relays are on PCB. All relays are placed on the back plane straight at the RCA and XLR connectors (I dropped the LEMO connectors and Allen may shake is head reading this...
The volume attenuator is a binary attenuator made using the same Pickering relays and the log scale is made in software in the AVR micro-controller used. Nice user interface made inside the AVR-controller and read out in a nice vacuum florescent dot matrix display.
Everything is controlled by an Apple alu remote control - how cool is that!?
Microcontroller... xtal... digital noise near the analog circuits... OMG! Nelson Bass and friend f*ck*d up the brilliant design of Allen Wright!
No we did not. We have incorporated latch circuits to hold the relays while the micro-controller can go into standby mode. Only waking up the micro-controller when using the remote control.
Only one switch is available - the power switch on the backplane of the power supply unit!
I'm happy that I'm not alone building this extreme preamp - Claus is around.
And the power supplies (both filament and high voltage) can easily be changed if future upgrades demands it. (read: if this preamp should not be the last word in preamps.
)I haven't heard any of Troels Gravesens speakers yet. But Troels seems to be an experienced speaker builder.
The Decware ZOB is a great speaker if you don't have massive bass requirements. But I'm used to deep, fast and massive bass from my CS2 clones so I'll build the HDT and try the broadcast system described by Steve. Beware that the ZOB/HDT is just for fun and I don't expect this system to take the price over my CS2s (next week they will be upgraded to CS2.3 clone status
Thiel CS2 / CS2.3 clones? The commercial Thiels bass output doesn't go that deep. Well at least on paper and when I have heard them.
What differs from the SuperReg? Hybrid rectifier... are you saying, part tube-based, part SS diode based? What was the reasoning for this?
Furthermore the PSU is choke loaded into 15H R-filtered to another 15H (both Lundahl) and the shunt regulators are discrete designs of Manfred Huber (maybe you remember the motor control unit for the Teres turntable?). Nothing but ground floor noise is showing up on my FFT analyzer... 300 Volt and pumping more than 100mA pr. channel.
This sounds promising. Few commercial products use proper chokes these days and the ones that do tend to sound better.
Last but not least I use Pickering low cap relays throughout instead of ELMA-switches. Audio signals are hardwired to the relays and control and voltages for the relays are on PCB. All relays are placed on the back plane straight at the RCA and XLR connectors (I dropped the LEMO connectors and Allen may shake is head reading this...
I have heard of Pickering in the professional studio equipment arena. Never used anything to know how good it is. I also have heard of Penney & Giles for top potentiometers (volume attenuators), but the cost is very high!
The volume attenuator is a binary attenuator made using the same Pickering relays and the log scale is made in software in the AVR micro-controller used. Nice user interface made inside the AVR-controller and read out in a nice vacuum florescent dot matrix display.
Everything is controlled by an Apple alu remote control - how cool is that!?
I like the dot matrix display. Is it displaying volume and in what form? Apple remote - you mean you have remote control with an iPhone?
Very good.. no clock noise. Are the latch circuit relays noisy when they switch?
Can you send me some pics of the build?
And send reply by way of PM as we just derailed the thread topic
Ill stop here. I have a hard time clarifying myself in english.
At least I said is was wrong on some of the things. I still think many could have made the same conclusions as i. And still think the other things are relevant. Zaph should pay more attention to the timedomain when designing boxes, and do better graphs. Troels should write about his relasions with the bussiness (like is do on my page). I linked to a design like the one Troels made, that didnt have the rippels, so it should be possible.
But yes. I was wrong about the course of the ripple. It was the box, not the speakerunit. I still dont like it. But yes, i was wrong.
At least I said is was wrong on some of the things. I still think many could have made the same conclusions as i. And still think the other things are relevant. Zaph should pay more attention to the timedomain when designing boxes, and do better graphs. Troels should write about his relasions with the bussiness (like is do on my page). I linked to a design like the one Troels made, that didnt have the rippels, so it should be possible.
But yes. I was wrong about the course of the ripple. It was the box, not the speakerunit. I still dont like it. But yes, i was wrong.
Maybe the moderator will move the RTP3C/D part of this thread to: http://www.diyaudio.com/forums/tubes-valves/151733-vacuum-state-rtp3c-4.html#post2129656 ?
I use Xover & the equalizer within the media player Foobar and two external NONOS USBDACs to replace the Behringer DCX2496. I believe this to be way better than converting analog to digital and do the DSP thing and convert it back to analog. The drawback is of course that I can't use any other source than Foobar. But any other source is not needed as this setup outperforms everything else I've heard (including TT).
The current sourced shuntregulator designed by Manfred Huber is fully discrete and don't need an external PSU. I like KISS and the regulator is much smaller than Allens. I like it small to. And way bigger heatsinks. Versatile for the future...
Both regulator designs perform extremely well so don't care which to use.
The hybrid rectifier should have the speed of the SS and the sound of the tube. This principle is claimed by Lundahl to avoids the very high voltage of an all tube rectifier and uses the transformer more efficiently. Check this.
Are you forced to use a potentiometer look out for the linear Vishay P11 cermet types.
The remote control is this one from Apple:
And from my soon to be removed website:
No the Emerald Physics CS2/CS2.3 and they go DEEP.
I use Xover & the equalizer within the media player Foobar and two external NONOS USBDACs to replace the Behringer DCX2496. I believe this to be way better than converting analog to digital and do the DSP thing and convert it back to analog. The drawback is of course that I can't use any other source than Foobar. But any other source is not needed as this setup outperforms everything else I've heard (including TT).
I first build Allens design from the preamp cookbook and later modified after tips from Allen on the web. This regulator needs a separate PSU for the opamp.
The current sourced shuntregulator designed by Manfred Huber is fully discrete and don't need an external PSU. I like KISS and the regulator is much smaller than Allens. I like it small to. And way bigger heatsinks. Versatile for the future...
Both regulator designs perform extremely well so don't care which to use.
The hybrid rectifier should have the speed of the SS and the sound of the tube. This principle is claimed by Lundahl to avoids the very high voltage of an all tube rectifier and uses the transformer more efficiently. Check this.
IMO avoid any potentiometer no matter the cost. Use relays or swicthes.
Are you forced to use a potentiometer look out for the linear Vishay P11 cermet types.
Think Madrigal Mark Levinson and you get the idea of the information in our display. We have been through the Mark Levinson user manuals and we believe we came out with a way more intuitive user interface design as we also love the products from Apple.
The remote control is this one from Apple:
An externally hosted image should be here but it was not working when we last tested it.
The relays are used for switching and I don't expect them to make any kind of noise in the signal path. The latch circuit just hold the relay if we want them turned on. A kind of memory circuit to remember the state for the relays.
http://www.diyaudio.com/forums/clubs-events/150816-diy-event-denmark-19.html#post2056819 post #182-186. Preamp & PSU without the frontplates made of wood.
And from my soon to be removed website:
An externally hosted image should be here but it was not working when we last tested it.
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