The SMPS are easily found on eBay. Are you going to build it as a monoblock set or on one chassis? I have one SMPS if you need it.
i also have found the IEC line filters on eBay, just search for "IEC filter" you should get a few hits there. Those were the cheapest. Digikey, Farnell, and the other big distributors all carry them too but, again, the cheapest I found were on eBay.
As far as the 5752 goes, Bruce will have to comment on that.
There is one other thing that I found was not on the schematic, it is the filter between groung and groung mains. I used a 0.33 Evox X2 series cap in parallel with a 5K resistor (I think it was 5K I will have to look for sure, Bruce may comment).
! love the sound with the SL7!
I also have a very nice custom built set of monoblock chassis I built for a second set of these...they are built with Canary, Rosewood, Oak, and Madera with a recesses aluminum top plate. I also have the access plates to mount the IEC filter, switch, RCAs and binding posts to that fits perfectly with these chassis. I decided not to build a second monoblock set so I am going to sell them....somewhere.
Sincerely,
Jeff
i also have found the IEC line filters on eBay, just search for "IEC filter" you should get a few hits there. Those were the cheapest. Digikey, Farnell, and the other big distributors all carry them too but, again, the cheapest I found were on eBay.
As far as the 5752 goes, Bruce will have to comment on that.
There is one other thing that I found was not on the schematic, it is the filter between groung and groung mains. I used a 0.33 Evox X2 series cap in parallel with a 5K resistor (I think it was 5K I will have to look for sure, Bruce may comment).
! love the sound with the SL7!
I also have a very nice custom built set of monoblock chassis I built for a second set of these...they are built with Canary, Rosewood, Oak, and Madera with a recesses aluminum top plate. I also have the access plates to mount the IEC filter, switch, RCAs and binding posts to that fits perfectly with these chassis. I decided not to build a second monoblock set so I am going to sell them....somewhere.
Sincerely,
Jeff
Here is a pic I had on this computer of one of my oddblocks. It is sitting next to a point to point from scratch build of the K-12G. The K-12G was the purpose of the pick but the oddblock just happened to be next to it. I will post several picks soon of the finished products.
Jeff
Jeff
Attachments
Jeff, thank you very much for your response! I am planning on building them as mono blocks with all Edcor Iron. Your mono block looks fantastic!
I am not having luck locating the correct SMPS for 12VDC 3A or 5A. I saw some that were $150++ and were huge. Is there a link to the correct type?... Ahh, too bad you don't have two SMPS's that I could buy from you.
However, I did find an IEC line filter. Will this do?... Schaffner - FN9233-10-06 - Allied Electronics
Ok, not sure exactly where the additional RC goes. Did you place the parallel 0.33uF Evox x2 cap + 5k ohm between the AC mains ground after the 100R in the line filter, and the ground following the rectifier in the PSU?...
Thanks!
I am not having luck locating the correct SMPS for 12VDC 3A or 5A. I saw some that were $150++ and were huge. Is there a link to the correct type?... Ahh, too bad you don't have two SMPS's that I could buy from you.
However, I did find an IEC line filter. Will this do?... Schaffner - FN9233-10-06 - Allied Electronics
Ok, not sure exactly where the additional RC goes. Did you place the parallel 0.33uF Evox x2 cap + 5k ohm between the AC mains ground after the 100R in the line filter, and the ground following the rectifier in the PSU?...
Thanks!
look for a power supply for a laptop or similar. Google is your friend... or here
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That power filter is perfect and cheaper than the ones I have found. Thanks for finding those, I will buy mine from here now! Yes, the laptop SMPS is what you want, you can find them off eBay too by searching on google. I think deepsurplus.com may have some too. Should be able to buy them from 10-15 bucks each.
I bought mine on eBay from a ebay store that sold laptop computers and accesories for about 12 bucks.
Jeff
I bought mine on eBay from a ebay store that sold laptop computers and accesories for about 12 bucks.
Jeff
The X2 cap and resistor are place between the power ground network and the groung mains. For instance, the green lead on most IEC filters is the earth ground and this is securely grounded to the chassis. The ground ( - leg) of your power supply will need to be at some point connected to earth main (chassis). this is the point of junction between the 2 and this is where this parallel cap and resistor goes.
Jeff
Jeff
I just ordered these versatile 12V 3.5A SMPSs on ebay. The voltage is also adjustable. The dimensions are 4x3x1.5in. It's better than the plastic enclosed types that you have to strip away. They're $15 including shipping.
Single Output 12V 3.5A Switch Switching Power Supply - eBay (item 230407845395 end time Dec-07-09 09:13:22 PST)
By the way, can I substitute a 5751 as a direct pin for pin replacement for the 12SL7 (i.e. no adjustments)?
Single Output 12V 3.5A Switch Switching Power Supply - eBay (item 230407845395 end time Dec-07-09 09:13:22 PST)
By the way, can I substitute a 5751 as a direct pin for pin replacement for the 12SL7 (i.e. no adjustments)?
Attachments
In preparing to build a system with a single KT88 Monoblock as it's base: I'm beginning to look at the other ends of the spectrum: namely drivers / speakers. I'm planning on putting two 8ohm parallel wired speakers on the 4ohm output. At 25W output, I'm having a hard time finding a good driver that will match the 8ohm / 12W-continuous requirement. So this would necessitate a ultra-high efficiency speaker? This seems to preclude the Jordan JX92S and possibly the Fostex FX120 for double-parallel setup or even singles as the rated wattage for a single speaker of either model is over 25w (kt88 monoblock rating). I'm considering building a single driver/large cabinet speaker as an alternative. Possibly with a Fostex FE108E Sigma? What are you guys running on your kt88 monoblocks? Any recommendations are appreciated. (Also, I'm not intending to rock out with my (@(4out, just a good system for listening even during a workout or dinner party). Many Thanks! James
Also: Diodes
I'm having trouble with conflicting information that I am getting regarding the types of diodes used in ODDwatt's Hi-test rectifier circuit and his heater voltage rectifier circuit.
For his new kit, STTH5 series (stth506D) diodes are used for the hi-test rectification (as per the review here at DIYAudio). These are 5A/600V diodes as opposed to the 1n4737 diodes at 1A/600V listed in the original diagram (original diagram used a prepackage SMPS for heater regulation) and directly contradicts the review's suppled diagram stating that MUR type diodes were used (which do not have a 5A/600V diode in that series).
Traditionally, Oddwatt has used 5A/50V in his heater circuits (see his el84-6bq5 PP project) and 1A/600V for his hi-test rectifiers. I'm thinking the review might have it wrong in what was used for what.
I'm thinking the 1A/600V mur150G diodes are used in the hi-test rectifier and a 5A/ ??? V (maybe a STTh5 fast switch diode?).
Can anyone shed some light on this?
Thanks!
I'm having trouble with conflicting information that I am getting regarding the types of diodes used in ODDwatt's Hi-test rectifier circuit and his heater voltage rectifier circuit.
For his new kit, STTH5 series (stth506D) diodes are used for the hi-test rectification (as per the review here at DIYAudio). These are 5A/600V diodes as opposed to the 1n4737 diodes at 1A/600V listed in the original diagram (original diagram used a prepackage SMPS for heater regulation) and directly contradicts the review's suppled diagram stating that MUR type diodes were used (which do not have a 5A/600V diode in that series).
Traditionally, Oddwatt has used 5A/50V in his heater circuits (see his el84-6bq5 PP project) and 1A/600V for his hi-test rectifiers. I'm thinking the review might have it wrong in what was used for what.
I'm thinking the 1A/600V mur150G diodes are used in the hi-test rectifier and a 5A/ ??? V (maybe a STTh5 fast switch diode?).
Can anyone shed some light on this?
Thanks!
lets say you have a off the shelf 90db eff speaker. 1 watt will give you 90db of sound at 1 meter, assume your 2 meter away so that gives you 84db of sound. Thats the limit before hearing loss occurs.
Now lets get it cranked to 2 watts, or 87db, the OSHA maximum before hearing protection is required by law. Now lets crank it to 25 watts (an ungodly amount for a class A amp). Thats almost 100db from 7 feet away and causes hearing loss after 2 hours...
There is a reason why we have a guy here that designs amps for the first watt
I am using a pair of Fostex 167E drivers modified with a center cone. They are mounted in a pair of Chili Chang cabinets I built and they give excellent bass and soundstage. The project was not too difficult to complete. I also use them with a pair of Proac 2.5 Response clones which I highly recommend but this is a 2 way system.
I am not sure where you are located but I am thinking of getting rid of my Chili Changs to make room for a line array project. I am in Oklahoma, middle of the USA practically. If you are close you are welcome to take a listen.
Good luck with your project,
Jeff
Plenty of power
I also run my Proac 2.5 Response clones with these monoblocks and a pair of KT88 or 6L6's and there is more than enough power to drive these at 90dB or so eff. If you can swing the cost I highly recommend these clones. Probably the best speaker I have ever owned or even nearly heard. There is a guy selling some of the Scan Speak drivers over at the Swap Meet and I believe he has a few of the woofers for the 2.5's and a cut rate. The tweeters are only about $75 each as I recall. You could probably build a pair for under $500 if you searched for deals on the parts.
The original site for the plans is closed but can be found on any of the archiving websites and I think I even still have a copy of the plans and XO schematics somewhere.
Jeff
I also run my Proac 2.5 Response clones with these monoblocks and a pair of KT88 or 6L6's and there is more than enough power to drive these at 90dB or so eff. If you can swing the cost I highly recommend these clones. Probably the best speaker I have ever owned or even nearly heard. There is a guy selling some of the Scan Speak drivers over at the Swap Meet and I believe he has a few of the woofers for the 2.5's and a cut rate. The tweeters are only about $75 each as I recall. You could probably build a pair for under $500 if you searched for deals on the parts.
The original site for the plans is closed but can be found on any of the archiving websites and I think I even still have a copy of the plans and XO schematics somewhere.
Jeff
Help for a UK newb
Hi all,
Just wondering if anyone could help me source a UK shopping list for parts to build a pair of Odd Block KT88 push - pull monoblocks?
I am fairly new to electronics but am trying to engage my father (a true expert!!) after he had a bad accident earlier this year.
I've decided to build but am very worried about the DIY project being US based. Unavailable transformers and such like. Have been chatting to the old man about the project for weeks and don't want to let him down. Initially we were going to refurbish some old Quad II's, but after Dad saw the extortionate price they are going for he told me that we were much better off building something a bit more powerful and more modern. He is now completely fired up for the xmas holidays and commencing work after i have sourced the parts! Hope someone can help, we both really like this amplifier. Desperate to build it and annoy all and sunder at xmas with solder and instrument wire!
I have found this chassis that I hope will be acceptable with a bit of jigging about. ValvePower - Chassis
What do you think? Any better suggestions for UK alternatives?
I am on a £350 budget---ish
Thankyou very much in advance
Hi all,
Just wondering if anyone could help me source a UK shopping list for parts to build a pair of Odd Block KT88 push - pull monoblocks?
I am fairly new to electronics but am trying to engage my father (a true expert!!) after he had a bad accident earlier this year.
I've decided to build but am very worried about the DIY project being US based. Unavailable transformers and such like. Have been chatting to the old man about the project for weeks and don't want to let him down. Initially we were going to refurbish some old Quad II's, but after Dad saw the extortionate price they are going for he told me that we were much better off building something a bit more powerful and more modern. He is now completely fired up for the xmas holidays and commencing work after i have sourced the parts! Hope someone can help, we both really like this amplifier. Desperate to build it and annoy all and sunder at xmas with solder and instrument wire!
I have found this chassis that I hope will be acceptable with a bit of jigging about. ValvePower - Chassis
What do you think? Any better suggestions for UK alternatives?
I am on a £350 budget---ish
Thankyou very much in advance
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