Edcors should work well - I've experimented with their mid-range irons (8k to 8 ohm) with the Quickie circuit, both in series and parallel feed. (For the latter, I used 150H plate chokes and 3.0uF coupling caps). While there is definitely less power at 8 ohms, the Quickie seems to work great with Edcor transformers. An 8k to 250/32 ohms would be quite ideal.
The Official Guide to Converting your Quickie for Headphone Use
- Thread starter Doc B
- Start date
I recently completed my Quickie with the headphone conversion and would like to share my experience. Everything went swimmingly until I pulled the Speco transformers from their boxes to find they were almost exactly nothing like those described in the post. Although the boxes were labeled as T7010 transformers, mine were physically smaller, only had two wires on the secondary side, had seven wires on the primary side none of which were .625W and a completely different color code. Worse yet, two wires exited from the last notch in the bobbin leaving me with no idea which should be connected to the signal. While I can follow directions well enough to assemble a kit the finer details of electronics are beyond me and not having found any specifications for this newer version of the T7010 online I was (after a trouble night) left with the brainstorm of measuring the relative resistances between the 10W brown wire and the other wires. Having done this I settled upon the Violet wire as being that labeled as .5W which was the closest value available to the .625W suggested in the original post. If anyone can suggest a better selection than the 10W/0.5W that I settled upon, I'd greatly appreciate your input. In fact, I would enjoy hearing any suggestions on my implementation that might improve the sound of this lovely little amp.
Correct or otherwise, the Quickie has turned into a quite enjoyable little headphone amplifier. While the output is not substantial enough to drive my inefficient AKG K501 to anything above barely acceptable levels, it has proved a wonderful match for the Beyer DT880 (250 Ohm).
If it should be of any help, as best I can determine, this is the color code for the version of the T7010 I received:
Primary
Common: Black, 10W: Brown, 5W: Red, 2.5W: Orange, 1W: Yellow, 0.5W: Violet, 0.25W: Blue
Secondary
Common: Black, 8 Ohm: Red
Correct or otherwise, the Quickie has turned into a quite enjoyable little headphone amplifier. While the output is not substantial enough to drive my inefficient AKG K501 to anything above barely acceptable levels, it has proved a wonderful match for the Beyer DT880 (250 Ohm).
If it should be of any help, as best I can determine, this is the color code for the version of the T7010 I received:
Primary
Common: Black, 10W: Brown, 5W: Red, 2.5W: Orange, 1W: Yellow, 0.5W: Violet, 0.25W: Blue
Secondary
Common: Black, 8 Ohm: Red
Paul Joppa
Moderator
That news is quite distressing. When we chose the Speco from a field of more than a half dozen candidates, we did so because the transformer we had been using changed without notice, and the new version was quite inferior. If the Speco has changed substantially, we may have to go through that exercise again. Stay tuned ...
Paul Joppa said:
Inquiring minds want to know....
Looking at the S.E.X. page seems the Specos are currently NOT useable. My ones are the "old" style so lucky me!
Are youse guys gonna sell the Stereomour outputs separately for headphone conversion? Would these be a big up from the Specos? Better bass? I would assume they would cost more then the cheapsy old Specos.
InfernoSTi
New member
Where did you order those from? Do they look like these? http://www.amazon.com/Speco-10W-70V-Line-Transformer/dp/B001MJFB8E/ref=sr_1_1?ie=UTF8&m=A3AFCSA6JU2B0W&s=merchant-items&qid=1304387790&sr=1-1 I think the specs listed are the same as the old specs but the model number isn't listed.
John
John
SPaulMac said:I recently completed my Quickie with the headphone conversion and would like to share my experience. Everything went swimmingly until I pulled the Speco transformers from their boxes to find they were almost exactly nothing like those described in the post. Although the boxes were labeled as T7010 transformers, mine were physically smaller, only had two wires on the secondary side, had seven wires on the primary side none of which were .625W and a completely different color code. Worse yet, two wires exited from the last notch in the bobbin leaving me with no idea which should be connected to the signal. While I can follow directions well enough to assemble a kit the finer details of electronics are beyond me and not having found any specifications for this newer version of the T7010 online I was (after a trouble night) left with the brainstorm of measuring the relative resistances between the 10W brown wire and the other wires. Having done this I settled upon the Violet wire as being that labeled as .5W which was the closest value available to the .625W suggested in the original post. If anyone can suggest a better selection than the 10W/0.5W that I settled upon, I'd greatly appreciate your input. In fact, I would enjoy hearing any suggestions on my implementation that might improve the sound of this lovely little amp.
Correct or otherwise, the Quickie has turned into a quite enjoyable little headphone amplifier. While the output is not substantial enough to drive my inefficient AKG K501 to anything above barely acceptable levels, it has proved a wonderful match for the Beyer DT880 (250 Ohm).
If it should be of any help, as best I can determine, this is the color code for the version of the T7010 I received:
Primary
Common: Black, 10W: Brown, 5W: Red, 2.5W: Orange, 1W: Yellow, 0.5W: Violet, 0.25W: Blue
Secondary
Common: Black, 8 Ohm: Red
Hello John,
I purchased mine from Wallco Industrial Electronics. They don't look anything like those in the Amazon photo; are rather generic in construction with a simple electrical tape type wrapping on the winding and in fact have no Speco nor T7010 markings whatsoever. The boxes did have Speco's branding and were sized correctly for the smaller transformers I received, but I'm getting the sinking feeling I may have received cheap substitutes. My fault for discovering Bottlehead so late in the game.
Stephen
I purchased mine from Wallco Industrial Electronics. They don't look anything like those in the Amazon photo; are rather generic in construction with a simple electrical tape type wrapping on the winding and in fact have no Speco nor T7010 markings whatsoever. The boxes did have Speco's branding and were sized correctly for the smaller transformers I received, but I'm getting the sinking feeling I may have received cheap substitutes. My fault for discovering Bottlehead so late in the game.
Stephen
InfernoSTi
New member
Thanks for the additional info, Stephen. I'm sorry you didn't get quite what you wanted but it sounds like you made the best of the situation! Excellent work! Glad to know the parts may still be available...I think I'll order and see what arrives since I have a Quickie that could be a headphone amp if all works out well....
John
John
Paul Joppa
Moderator
Caveat emptor. The picture and the taps on Amazon are correct, but the description says it weighs 5 pounds, shipping weight 11.5 ounces. The original Speco weighs 10.5 ounces, while the cheap crappy one weighs 5 ounces. Who knows which one you'll get? How many people will take the trouble to complain for a measly $6.29? Mounting holes are 2.25" on the original, 1.75" on the small one.
The edcor trannies are on their way. Should have them by Thursday. We're going to set this quickie up for dedicated headphone use. My 11 y/o son was hooked once I let him solder a few joints on the crack. He's going to do most of the work, I'll just help him where he gets stuck.
We're going to mount the top plate on a hammond 10x6 steel enclosure and add an alien dac for USB input
I'll take pictures of the edcors when they arrive
We're going to mount the top plate on a hammond 10x6 steel enclosure and add an alien dac for USB input
I'll take pictures of the edcors when they arrive
I finally got around to ordering the Edcor EM0735 transformers. Now that I have them before me, I have to admit that I probably have no business with a soldering iron in my hands. I have no clue as to how to hook the new transformers into my Quickie's circuit in place of the Specos. I'd imagined something like the signal ground going to both the C.T. and Common taps on the primary and secondary; the signal going to the 8K ohm tap on the primary and the output going from the 250 ohm tap of the secondary to the headphone jack, but I don't really look forward to smoking my little Quickie. I'd be very thankful for any help I can get on the proper wiring procedure for this transformer. The pin assignments for the EM0735 are as follows:
Primary
Pin 1 8K Ohm
Pin 2 Center Tap
Pin 4 8K Ohm
Secondary
Pin 5 250 Ohm
Pin 6 32 Ohm
Pin 8 Common
Thanks,
Stephen
Primary
Pin 1 8K Ohm
Pin 2 Center Tap
Pin 4 8K Ohm
Secondary
Pin 5 250 Ohm
Pin 6 32 Ohm
Pin 8 Common
Thanks,
Stephen
Ok, I ordered the transformers to convert to headphone use. Never, ever used headphones before. Need to now with the new baby. Since I am new to this I'd like a budget headphone to start. Are there any sleepers out there? Any recommendations for headphones that work well with quickie for under $100 or better yet under $50? Am I dreaming?
If you are willing to look for used gear you should be able to get the required high impedance cans in your budget.
As orignally suggested in this thread the transformers are wired for 250 ohm phones.
Look here.
http://www.bottlehead.com/smf/index.php/topic,546.0.html
I am currently using 600 ohm AKG 240Monitor wtih my Quickie. I think they sound fine but others my want a more sensitive set of cans as mine go just loud enouph for me. PJ suggested a different wiring for 600 ohm cans - see above.
My AKGs are from Ebay and were sub-$100 a couple years back. Don't recall exact price.
Kevin R-M
As orignally suggested in this thread the transformers are wired for 250 ohm phones.
Look here.
http://www.bottlehead.com/smf/index.php/topic,546.0.html
I am currently using 600 ohm AKG 240Monitor wtih my Quickie. I think they sound fine but others my want a more sensitive set of cans as mine go just loud enouph for me. PJ suggested a different wiring for 600 ohm cans - see above.
My AKGs are from Ebay and were sub-$100 a couple years back. Don't recall exact price.
Kevin R-M
InfernoSTi
New member
bainjs said:
Where are they available, please?
InfernoSTi
New member
bainjs said:
I think they are out of stock again....good to know they come back from time to time, however. I have a set and was hoping to purchase a second as a gift for a friend.
John
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