Hey
So I grabbed some vintage Bowers and Wilkins speakers built in 1982 and have found some specs, I'll attach here.
What I find weird is that it says the wattage is 15W protection circuit yet in the manual is says there is no wattage limit due to protection.
I have also owned the DM23 which have the same tweeter and it's said that they can have an amp from 10-100 watts. So really can it be true speakers this large are only 15W?
I am also thinking about building another amplifier as my Jean Hiraga 20W Class-A does not seem to give them the power they need so am thinking about an F5 Turbo which I've heard and built before for a friend and loved it!
87db
So I grabbed some vintage Bowers and Wilkins speakers built in 1982 and have found some specs, I'll attach here.
What I find weird is that it says the wattage is 15W protection circuit yet in the manual is says there is no wattage limit due to protection.
I have also owned the DM23 which have the same tweeter and it's said that they can have an amp from 10-100 watts. So really can it be true speakers this large are only 15W?
I am also thinking about building another amplifier as my Jean Hiraga 20W Class-A does not seem to give them the power they need so am thinking about an F5 Turbo which I've heard and built before for a friend and loved it!
87db
These speakers are certainly not limited to an amplifier power of 15W.
You may use them confidently with a much higher powered amplifier.
Only if you crank the volume up all the way will the overload protection circuit come temporarily into play and rescue the speakers from your excess!
You may use them confidently with a much higher powered amplifier.
Only if you crank the volume up all the way will the overload protection circuit come temporarily into play and rescue the speakers from your excess!
I've always had B&W's. They do seem to like high current drive, ie Class A amps. Try any of the Pass DIY amps depending on your budget. The Aleph J is the best in opinion with the newer CM8 s2.
The F5 isn't the best with these.
The F5 isn't the best with these.
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Thank you Galu
I'm probably also going to replace the capacitors if they are out of value as if they are the frequency response may be out and 1982 is a while ago!
KatieandDad
Well I just went crazy and got a load of large heatsinks so defiently making a Class-A amp
It says about Aleph J
"The Aleph J is a single-ended, Class-A, Mosfet power amplifier, with a Jfet driver stage. It utilizes the Nelson Pass 'Aleph Current Source' to greatly increase the overall efficiency of the output stage, with the benefits of more linearity, a higher damping factor, and greater stability into tough speaker loads, doing all this with less negative feedback than it's predecessors. The Aleph J is a regular kind of amp - a voltage source amplifier, requiring nothing out of the ordinary from the preamp or the speakers."
So you mean also the F5 Turbo would not be as good with these too? My Jean Hiraga 20W was not very loud on the DM16s but I wondered if it was something to do with my new laptops output levels, not sure.
The F5 Turbo is the best amp I've heard and had a lot more authority (is that more current drive?) hopefully not just because it was 50W instead of the original 25W but that there were other improvements that made me love the sound of that amp.
I'm probably also going to replace the capacitors if they are out of value as if they are the frequency response may be out and 1982 is a while ago!
KatieandDad
Well I just went crazy and got a load of large heatsinks so defiently making a Class-A amp
It says about Aleph J
"The Aleph J is a single-ended, Class-A, Mosfet power amplifier, with a Jfet driver stage. It utilizes the Nelson Pass 'Aleph Current Source' to greatly increase the overall efficiency of the output stage, with the benefits of more linearity, a higher damping factor, and greater stability into tough speaker loads, doing all this with less negative feedback than it's predecessors. The Aleph J is a regular kind of amp - a voltage source amplifier, requiring nothing out of the ordinary from the preamp or the speakers."
So you mean also the F5 Turbo would not be as good with these too? My Jean Hiraga 20W was not very loud on the DM16s but I wondered if it was something to do with my new laptops output levels, not sure.
The F5 Turbo is the best amp I've heard and had a lot more authority (is that more current drive?) hopefully not just because it was 50W instead of the original 25W but that there were other improvements that made me love the sound of that amp.
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What about Aleph-X
My audio gear (musician) is balanced
ALEPH-X - Pass Labs Clone Class-A amplifier PCB & schematic
My audio gear (musician) is balanced
ALEPH-X - Pass Labs Clone Class-A amplifier PCB & schematic
Note that a push-pull amp may be primarily class A but still able to move out into class B for the peaks, should you want to increase your rails but not the standing current (or, depending on your point of view build a high power amp you can hold into class A). If you're sure of the power you need, the single ended amps are fine. (The Aleph above is balanced single ended.)
Hey thanks
So you mean I can up the power of amps like the F5 Turbo which run in Class-A up to a point.
I think I'm sensible to go with around 50w with those speakers which I know needs a lot of cooling but luckily I got some good sinks!
So you mean I can up the power of amps like the F5 Turbo which run in Class-A up to a point.
I think I'm sensible to go with around 50w with those speakers which I know needs a lot of cooling but luckily I got some good sinks!
Mine seems to get along well with an old Yamaha B2, and even better results with a darTZeel MHB108 circuit based amp. 🙂
I have found in the street two beautifull DM14 last years...easy to feed while needed recap...the upper mid and tweeter sound is beautifull...
Yam B2 and most of those old Yam. sounded good...🙂 still have a cx2 pre I like a lot.
Yam B2 and most of those old Yam. sounded good...🙂 still have a cx2 pre I like a lot.
Yeah, I enjoyed it with the B2 for a bit but have since found an even better match in an amp based around the darTZeel NHB108 circuit. It's a far more evenhanded and natural sounding combination though surprisingly quite similar presentation to the B2 just with far better detail overall. Quite impressed with it.
Awesome find with the DM14. Still enjoying my restored 16's. The big caps limiting how deep the woofers go were removed and bypassed though as was the APOC protection circuit. More dynamic sounding and bass goes deeper now.
Wem; I know a guy who uses a class AB tube amp (ARC Ref75) for those and they sound very good with those, with his solid state amp (Nad M22 so class D) they sound lifeless., So it may be that they high Rout amplifiers more than others. Class A transistor amps like Pass/Firstwatt amps will do it also probally as they are much behaving like a tube amp on that, only without tubes 😉.
Are you sure your B-2 sound is not being robbed of details? Dd you bi-pass the selector assembly of the B-2? Any additional details of the Dartzeel circuit?
No, B2 is stock as it's on loan by a mate. It's not my amp. The darTZeel is simply far faster sounding with better fine detail, better control of the woofers. It's better all round. Course it's a tired old amp. Might improve with a full recap etc though then again that can sometimes have a detrimental effect on the sound as well so its a gamble. All I can definitely say is right now the system is significantly better with the darTZeel circuit amp. I have a mate round last week who has confirmed what I was hearing and has decided he now wants to source the same power amp. So yeah the B2 is nice with these speakers, though the darTZeel is better.
yes, 45 years old amps can get tired. B2 is a DC amp no caps in the signal path. The PSU does need to be rebuilt. Noisy carbon resistors and other components can keep the floor noise high. High floor noise can muffle some of the details. Changing the bulk caps and restoring the PSU makes a big difference in that amp. What else makes even a bigger difference is that the signal is routed via open air connectors and noisy pots. No way to get around that unless you directly bypass or implement a change to leverage low signal relays to route the signal.
So you did not really have a comparison there...not even apples and oranges. More like tomatoes and walnuts....both could pass for fruits at some level...but....nonetheless, the B-2 even at 45 years old is a serious contender. If you liked the clone as much, I am intrigued with the darTZeel clone. Could you please provide some details of the clone you have, such as source?
I would love to hear the original darTZeel. How does the clone compare to the original, any idea?
Cheers,
Peter
Any old second-hand amp will sound the same as any other amp. Spend your money on a large carpet because that will help your sound a lot more (even if you already have some carpeting).
B.
B.
I don't know about this speaker but many of them had protection circuits just for the tweeter. I could see 15W limit on the tweets.
True, if both amps are similar condition as in working as new (agnostic of actual age). Agreed on the carpet as well.
As accurate as can be considering the amps age. Like it or not, recap that B2 and it's not stock anymore so really there is no way to do an exact like for like comparison. The darTZeel NHB108 is on another level as well it should be given it's a new amp. I can't say how it compares to the original as you're comparing an amp thats a few hundred dollars vs $30k from Switzerland. Little doubt the real deal is better. How much better I'll never know. Costs more than my car.
Nonetheless, my darTZeel copy has had the Chinese caps in the power filtering section replaced with Mundorf MLytics and capacitance upped from 10,000uF to 15,000uF,and the cheap film bypasses for 0.1uf Jupiter Copper Foil. The power transformer had to be moved slightly forward, and one of the amp boards flipped upside down and a new hole drilled to accommodate the higher capacitance caps. The amp boards themselves however have not been touched. I remain impressed given the money spent.
This is the amp here: https://www.aliexpress.com/item/32847333882.html
This is what I'm using as a preamp for both amps: https://www.aliexpress.com/item/1005002111085039.html
VTL Reference D/A Convertor up front with a complement of 4x Mullard CV4024's: https://www.stereophile.com/digitalprocessors/vtl_reference_da_processor/index.html
Likely the VTL will need a recap at some point though right now it still sounds superb though somewhat midrange forward.
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