Transistor equivalent

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http://audiophilereview.com/subwoofers/what-audiophiles-are-getting-wrong-about-subwoofers.html

basically says your pre-amp is made from unobtainium .OR. you have to roll your own?

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You get something like: http://www.aliexpress.com/item/MCD3...2263977428.html?spm=2114.40010308.4.47.lcfeEU

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Here: http://www.caraudiohelp.com/car_audio_signal_processors.html basically states the EQ belongs in the trunk (boot) in a car audio system. You tune it for the speaker placement and acoustics and then after that "hands off".

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AG
I like folk music and I "impact process" and expand that with a 4bx. I am deficient hearing at 2600 Hz (Tinnitus). I agree boomy distorted lows are easier to spot.
The real deal is, the "100 W" speaker only had 30W dome tweeters in them with a 1.250 fuse in the speaker.



Sorry - no shaving socket. I don't have an answer to "Why include one?"

It doesn't include a separate power supply,nor weight 298 lbs either: http://passlabs.com/images/uploads/manual/pass_xs_brochure_2014.pdf
 
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Sorry because I make you did a lot of work. I will never forget you, spec.
About amp:
Will I need woofer-mid-tweeter for each channel?
How big are the speakers and sub boxes? I only want to know a relative sizes. 30cm sub and woofer.
I don't need preamps, just pre for sub amp
 

That's OK Nikolai- I get overwelmed sometimes, especially with all the flak from some people on ETO- most are helpful though.

(1) For the left and right speakers I suggest that you have a 5 to 6 inch bass/midrange speaker plus a 1 inch dome tweeter. I would also suggest that you follow a standard design. We can work out the details later but cabinets would be bookshelf size.
(2) I haven't done a bass sub cabinet but I know the theory and will investigate an report back. The sub speaker size will depend on what you want. I will make a sugesstion and you can see if it suits your room.
(3) One thing to establish: what speaker chassis are you going for.
(4) would you consider buying ready made speakers, possibly second hand for the left and right speakers?
(5) I suggest that you do need a separate preamp to drive the power amp well and to give all the facilities you will need in the future. The preamp case will not be anything as complicated or big as the power amp and a heatsink will not be required. This is the way that upmarket systems are made. This approach also gives a modular system so that you can more easily mix and match in the future. The preamp will have a dual concentric volume control so that a separate balance control is not required. It will have a 5 way switch to select the various inputs and it will have any other crossovers for the sub, frequency shaping that you may want and so on.
(6) In the future you will almost certainly want a DAC to convert digital signals: MP3, FLAC and so on into high quality analogue to feed the pre amp.

The way forward for this program is to build the case, but first you need to select the transformer, because that will dictate the depth and posssibly the height of the Amp case. Once the transformer is selected the case deign can be finalised and the case constructed. Then only one amp should be built, fitted and tested. This is a critical task. you may have to add capacitors, change values , change wiring etc to get the amp running right. Once that stage is complete the other two amps can be built, incorporating the mods learned from the first amp. Then the three amps need to be tested. once that is done you can button up the power amp and you will have a nice unit tha will last you, in theory, for ever. If in the future you want to fit more capacitors in the PSU to improve the soud there is space to do so. If you want to add protection circuitry and so on, likewise. You will also be able to fit differnt amp boards.

I am intending that space will be provided for four TO-3 transistors for each amp board. That way you will be able to fit all the major package types and also fit four transistors, rather tahn two, in the future, which will give you maxiumum flexibility.

The preamp is a completely differnt design excercise and the parts need not be expensive. Once again you can fit standard parts to start with and later upgrade.
 
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This is what your left and right speakers should probably look like. The B&W 601 S3 look and sound nice and you can get a pair quite cheaply these days if you shop around. They are the previous version of the speakers I hope to get. You may even find that you don't need a sub with them: https://www.ebay.co.uk/itm/B-W-DM601-S2-Speakers-and-Atacama-Stands-/221987335408


Monitor Audio speakers are also available at a good price. They are well known for a powerful and deep base and nice top
 
Ok, spec. I will consider about speakers. 100WW spkrs will fine. About sub and woofer I know alum and steel chassis are available, alum are more expensive than steel.
I know that preamp not big, not comsume a lot current, just hundred miliamps total. But I prefer discrete transistors to opamps. (No ICs in my amp will be really cool).
Can you give some components I will use, my brother in the Ho Chi Minh City may can have me to buy, because he will come back to Hanoi in Feb-2016 so I want information early
 

Hi Nilolai,

Good afternoon from the UK. It is 12 05 pm (noon) here.

I have finally finished configuring all the apps on my laptop after a major upgrade, including Windows 10 and also transferred a lot of data to a new NAS. I now have a 500GB flash HDD as the main C:/ drive and put the original 1TB HDD in the laptop bay. Boy is the laptop fast now.

I know you probably think I'm an old kill-joy, but I have your interests at heart, and I am also keen to see a successful project with the minimum expense for you. In view of this, I really think you should leave the bass sub for now. Sure have the facility for fitting a bass sub. That is a good contingency for the future but just get the two channels, L&R, going and enjoy listening to that. I think you will be amazed how much bass you will get. Also, as ag has done, we can augment the base if you want and make your Dad's foundation shake just the same. On some of the speakers, ESP14s for example, a base sub would be a joke and would have ruined the bass slam that the speakers produced, and I'm talking about low low bass too. I am not sure what hifi systems you have been listening to- some high end equipment maybe, but I think you are in for a shock when you hear to the type of system that I am proposing.

Also, listen to me, the right opamps in the preamp will sound fabulous. I have a DAC headphone amp that would blow your mind, and that uses four audiophile opamps. Things have changed now about opamps.

But even so, you can fit any amplifiers, including discrete, you like once the preamp is built and functioning. This is what you do: where the opamp fits you fit a good quality turn pin socket, then all you need to do is build your discrete opamp and plug it into the same socket- no problem. You can also roll the opamps- that's what the audiophile boys call changing the opamps to suit your taste.

The preamp needs quite different design and build to the power amp. It will be a nice project, which if done right, will be a pleasure to build and listen too. It will also look good and will be unique- or boutique as the aficionados like to say. There is a fundamental axiom when getting something near perfect: KIS= Keep It Simple. Just think of a solitaire diamond.

OK about components. I will work on a list which we can discuss and then refine to get an optimum price/performance. Sorry to keep on but what is happening about the transformer in the power amp. Are you going to buy a torroid or make one?

spec
 
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I do have a subwoofer. It is 18" in diameter, is very heavy and is rated at 900W RMS. It is brand new and has never been used. I got it for low cost when I worked for a Pro-Sound manufacturer. I was thinking of selling it at a car audio sound pressure contest that can be heard miles away. You know, that is where stupid guys try to blow up their car with loud sounds.
 

Shame, it would have been the ideal size for Nikolai's sub, but it's not quite powerful enough
 
Hello, it is 22:11 now in Vietnam, cool night, only 21°C. Hmm the spring so hot. Yesterday I worn t-shirt but still heavy sweating when did hand weights exercises.
Agree you that simple is the best.
DAC, I have heard before but still searching good converting-IC for converter.
I hope my project will not become a vampire .
Not found toroid core yet, I am too busy. I have a big EI transformer, I will post image and size than can you let me know max power of it.
 
I have a JVC 5.1 receiver that is very big and heavy. It was thrown away by an audio store because it has damage caused by it being dropped and the corner of a pcb is gone. I do not need it but I might try fixing it someday.
 
Nikolai Petrenko said:
...Agree you that simple is the best.
Click to expand...

KISS has it right with his tag.

Nikolai Petrenko said:
DAC, I have heard before but still searching good converting-IC for converter.
Click to expand...

Sabre 9018 and Wolfson 8741 for example. There are many more.
The two most important thing about a DAC amp is the chip itself and also the implementation. You can guess what I am going to say- don't even think about building a DAC. I do not exaggerate when I say it would be impossible. Sure you could easily build one that would output good audio but not audiophile. There is no reason why you should not build a first class headphone amp though.

Nikolai Petrenko said:
I hope my project will not become a vampire .
Click to expand...

vampire= blood sucker (suck all your money) ?

Nikolai Petrenko said:
Not found toroid core yet, I am too busy. I have a big EI transformer, I will post image and size than can you let me know max power of it.
Click to expand...

Shame not have a toroid but not the end of the world- might make the case a bit bulky though.
 
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audioguru said:
I have a JVC 5.1 receiver that is very big and heavy. It was thrown away by an audio store because it has damage caused by it being dropped and the corner of a pcb is gone. I do not need it but I might try fixing it someday.
Click to expand...

Sounds like a good project for a Sunday afternoon. I love repairing scrapped items like that, but is it SM?
 
More speakers:**broken link removed**

**broken link removed**

https://www.ebay.co.uk/itm/MISSION-737R-SPEAKERS-2-WAY-LOUDSPEAKERS-WITH-ORIGINAL-1984-SHOWROOM-STANDS-fwo/131641552306?_trksid=p2141725.c100338.m3726&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=20150313114020&meid=45fc71abbea74d20a4bb5438508b4b79&pid=100338&rk=2&rkt=29&sd=231742929963

http://www.ebay.co.uk/itm/QUALITY-PAIR-OF-MISSION-702e-SPEAKERS-in-V-G-C-LIGHT-USE-ONLY/361344299445?_trksid=p2141725.c100338.m3726&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=20150313114020&meid=45fc71abbea74d20a4bb5438508b4b79&pid=100338&rk=1&rkt=29&mehot=pp&
sd=231742929963

https://www.ebay.co.uk/itm/Mission-774-Floor-Standing-Speakers/121851855545?_trksid=p2141725.c100338.m3726&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=20150313114020&meid=45fc71abbea74d20a4bb5438508b4b79&pid=100338&rk=11&rkt=29&mehot=pp&sd=231742929963

https://www.ebay.co.uk/itm/Tannoy-Mercury-M3-Main-Stereo-Speakers/121690524061?_trksid=p2141725.c100338.m3726&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=20150313114020&meid=45fc71abbea74d20a4bb5438508b4b79&pid=100338&rk=10&rkt=29&sd=231742929963

https://www.ebay.co.uk/itm/Celestio...b4b79&pid=100338&rk=20&rkt=29&sd=231742929963
 
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