All the capacitors are "in line"..so no shunt caps & the signal goes through them to the cone...so best to specify better, & the mid is dealing with a 750Hz & 2.6kHz crossover points split...
I'd go for the thicker wire inductor (13AWG) on the woofer as you have a large cone & power handling....thicker wire is best...
Resistors....so the 122w Mills...& if you want 4 Ohm you could by a 1.8 & a 2.2 Mills 12w & place them in series to give you 4 Ohm...
I had a look at that link...& can't find it stating 1:12 type??.......& I don't know a huge amount on transformers.....Hi-fi collective do them...But i can't find the required type...if it were me I'd email them with the speaker details & ask for their recommendations...
https://www.hificollective.co.uk/components/transformers.html
P.S. what wiring are you going for internally & what binding posts?
I have looked through all those transformers at HiFiCollective. Digging on the internet I found this thread on Audiokarma about the HPM-150 1:12. It seems like a good starting point. Have emailed hificollective and see what their recommendations are. This is the one they recommended as a starting point.
Internally - I was going to follow the British build on YouTube - he used speaker wire.
I had picked out Audtek 16 AWG speaker wire and I have quite a few industrial Terminal Strips like these laying around. For Binding posts - I was going to buy this set and just scavenge them off the plastic piece :-D
What would you recommend?
Internally - I was going to follow the British build on YouTube - he used speaker wire.
I had picked out Audtek 16 AWG speaker wire and I have quite a few industrial Terminal Strips like these laying around. For Binding posts - I was going to buy this set and just scavenge them off the plastic piece :-D
What would you recommend?
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Note - the 'recommended' transformer above was recommended on the AudioKarma thread - havent heard back from HiFiCollective yet.
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Ok so you got the transformer from a thread on the subject..had a look...... & looks ok.
Hi-fi Collective aren't in...it is currently 5PM on a Sunday here in the Uk where they are..so not hearing from doesn't surprise me!
If you read my thread I used Test measurement wiring & sockets & plugs..
MC/Staubli 2.5mm CSA, Silivolt-1V, OFC copper, wire, Silicone Jkt. 5m for the internal wiring.. which is about 13 to 14 AWG
MC/Staubli 4mm Shrouded test plug, Gold plated brass body 32A, 1000V in red & black for the "binding posts"..this meant I had to use their plugs on the external wire.
All of this to reduce the amount of extraneous metal in the signal chain....It might be too much for you, but I would strongly recommend the wire as its very thick & OFC with a soldering iron heat resistant silicon cover....which is better & longer lasting compared to plain PVC...
70.7V, 15 Watt, to 4 or 8 Ohms.
15W in 4r is 7.746 Volts. 70.7/7.746 is 9.1:1.
15W in 8r is 10.95 Volts. 70.7/10.95 is 6.45:1.
Agree, it seems like a near-miss.
For the 1:12 transformer ... can I make two?
I found this kit : Make your own transformer kit
Kit is Maybe not the same - how hard would it be to make the transformers I need?
I found this kit : Make your own transformer kit
Kit is Maybe not the same - how hard would it be to make the transformers I need?
If you needed 1:12 TURNS ratio... a 70v speaker line transformer with a 5 watt tap would get pretty close (4.25 watts is the exact figure... a 4 watt tap would be pretty much dead on- 1:12.35 turns ratio- if you can find that). <- Quote is link to original discussion
This might be the right transformer?:
https://goknight.com/atlas-sound-ht47-high-quality-4w-audio-transformer-70-7v/
70v with a 4 watt tap. - BUT the Frequency response stops at 12kHz... or am I mixing up signal Hz with output to the supertweeter?
Does the Frequency response affect anything in this case?
This might be the right transformer?:
https://goknight.com/atlas-sound-ht47-high-quality-4w-audio-transformer-70-7v/
70v with a 4 watt tap. - BUT the Frequency response stops at 12kHz... or am I mixing up signal Hz with output to the supertweeter?
Does the Frequency response affect anything in this case?
Not "stops". Drops 1dB. In this situation, it may be -3dB at 24kHz.
And sometimes production specs are just copied from some other part. This one may do better. The ceiling-speaker market hardly cares past 5kHz.
Since it may be the only 20 buck part you can find to do the job, I suggest you buy and try.
Hmmm I see...completely livable at the 1dB -2 dB loss. Cool
Would getting the HT87 be best? .6dB loss and slightly overbuilt for the wattage?
Or same circuit for the 4 Tap whether in the larger or smaller unit?
Would getting the HT87 be best? .6dB loss and slightly overbuilt for the wattage?
Or same circuit for the 4 Tap whether in the larger or smaller unit?
Since this thread is about inductors, I am hoping that I have placed this question in the right place. It is this>> I have seen round wire and even flat wire used in inductors, but I do remember way back in high school, Century brand welders were using square wire because of the improved spacing/winding of the wire being more perfectly stacked. I have not seen this thinking since, or maybe I am just not aware of this still being done. It makes better sense to me though.
Older JBL loudspeakers used milling to turn round wire into rectangular wire, for improved space utilization in (very expensive) voice-coil magnetic gap. (Also for neater geometry of the far-end return lead.) Millions of speakers have worked well without this refinement.
In a transformer it would allow marginally smaller iron core. Hard to justify unless weld/pound was a key market feature, like portable welders.
Thanks for this explanation. Always had a fascination for what seems to be the simpler side of electrical theory/practice.
Hello nice community, can you now give a feedback how have become the crossover for the HPM150. Maybe show a picture and describe how has sound changed?
Kind regards Michael
Kind regards Michael
Hi,
Will do. I have one built (going slow to make sure I get it right). It is relatively ugly as I used parts I had around.
Havent tested it yet...
If you look on YouTube there is a guy who does 3 parts for HPM-150 restore. He has demonstation of after...
Currently trying to figure out how to wire in the transformer , which are in and which are the outputs (Going to the Super Tweeter).
Will do. I have one built (going slow to make sure I get it right). It is relatively ugly as I used parts I had around.
Havent tested it yet...
If you look on YouTube there is a guy who does 3 parts for HPM-150 restore. He has demonstation of after...
Currently trying to figure out how to wire in the transformer , which are in and which are the outputs (Going to the Super Tweeter).
That would be super nice! But I'm interested in the parts HiDave suggested... I also intend to make new crossovers for my HPM150 with Jantzen coils and capacitors if it brings good sound advantages.
I watched this video... Only he used foil coils, which is too much for the drivers! But good and expensive 100v aluminum capacitors from Jantzen.
Yes the new transformer has several outputs not like original only 2 🙂
I watched this video... Only he used foil coils, which is too much for the drivers! But good and expensive 100v aluminum capacitors from Jantzen.
Yes the new transformer has several outputs not like original only 2 🙂