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  #11  
Old 24th January 2018, 03:15 PM
bob orbell bob orbell is offline
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Default Re: Another set of secondhand speakers

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Originally Posted by Richard View Post
I'd get the Bada checked though first Stuart as 50W would be plenty with circa 90dB speakers.

Looking at a pic of the insides someone should be able to fit pre-out and power-in RCAs on the back but check the pre topology as it may need to see a high impedance (>100K) and the likes of all Quad ss amps are 20K
I agree with Richard, 50 watts and 90 dB should blow the bloody doors off. BOB
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  #12  
Old 25th January 2018, 12:14 PM
Black Stuart Black Stuart is offline
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Default Re: Another set of secondhand speakers

Richard,
It would be good to get someone with real experience to check out the Bada, It's been completely dismantled and I've replicated the cut-outs above two of the Mosfets so all 4 have an exit path for heat dissipation and intended to raise the potted mains above the 2 inside mosfets. The potted mains is good no hum problems at all. I'm sure the Chinese have 'copied' an old design, it's what they tended to do. It has what all amps should have a slow start circuit. The impedance might well be a problem as you say.

The only tubes I want to keep now are the pre-amp ones, I find the mosfets have power and the ability to render a sweet top-end. I'm very happy with the Bada PH12 h/amp which uses virtually the same pre-amp design. Once I got rid of the awful Red Wimas and used the K73-16s 0.1uF & 1uF caps. Keeping the two amps has the real advantage that I have enough of the 6F8G and 1578 tubes to last me and of course the wonderful sound of this combo of tubes, which have now become really expensive and the 6F8G Tung Sol RP is virtually unobtainable.

Bob - I can play the amp very loud but it 'ain't pleasant'. Is it the amp clipping or the awful materials that the French use to build with. Ye old stone walls with or without a hard plaster finish are not conducive to a good sound. Older houses have internal walls made of hollow red clay approx. 2.5"/65mm, believe it or not, the French also uses these thin clay blocks as party walls, same as Spain They are so hard you have to use special 'tacks' to pin anything to such a wall.

The house we should be moving to was built around 1960 so, honeycombed clay blocks externally and these same thin clay block walls internally. Modern houses are even worse with ceramic tiled floors and single plasterboard walls - both very noisy and suck the bass right out of music. Luckily the floors in this house are t&g pine as are a lot of the ceilings, so that's a good thing. So it's a case of vamos a ver/ let's see.

I much prefer listening to music via speakers but h/amps do have the advantage of the listening room/space being irrelevent.
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  #13  
Old 25th January 2018, 10:15 PM
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Greg. Greg. is offline
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Default Re: Another set of secondhand speakers

Stuart, my early 1960’s house (you’ve been here) is constructed with a high quantity of the red clay hollow bricks. All is rendered followed by a plaster skim. I get no acoustic problems owing to this construction. Certainly there is no bass suck out.
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  #14  
Old 26th January 2018, 10:51 AM
Richard Richard is offline
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Default Re: Another set of secondhand speakers

Hi Greg, I wonder if Stuart means those big hollow clay building blocks about breeze block size rather than our bricks with frog holes?
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  #15  
Old 26th January 2018, 10:57 AM
Richard Richard is offline
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Default Re: Another set of secondhand speakers

Hi Stuart, you need to get the amp on a sig gen and scope and sweep it at a few different power outputs to see if it's distorting or try a known good amp for comparison in the system
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  #16  
Old 26th January 2018, 11:06 AM
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Greg. Greg. is offline
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Default Re: Another set of secondhand speakers

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Hi Greg, I wonder if Stuart means those big hollow clay building blocks about breeze block size rather than our bricks with frog holes?
No, I mean the breeze block size hollow blocks. My house is littered with them. Can be a pain when drilling into them looking for a good anchor for hanging heavy objects.
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  #17  
Old 26th January 2018, 11:17 AM
Richard Richard is offline
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Default Re: Another set of secondhand speakers

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No, I mean the breeze block size hollow blocks. My house is littered with them. Can be a pain when drilling into them looking for a good anchor for hanging heavy objects.
Ah, ok, I didn't know we used them over here.
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  #18  
Old 26th January 2018, 06:56 PM
Black Stuart Black Stuart is offline
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Default Re: Another set of secondhand speakers

As Greg says I know his house and the materials used to build at that time. The bricks would be 'flettons', a very brittle brick. The suck out Greg, is from single skinned plasterboard onto timber stud. What the French use today is even worse - galvanised steel stud and the plasterboard is screwed onto it. The joke is that this galvanised steel is part of an insulation process LOL.

I've seen for the first time just up the road a start to finish (well nearly) new build house - unbelieveable **** and with the heavy rain we've had there was a small lake beneath and around the house that they had to pump out. DPC - don't make me laugh, what they have used as internal walls, I could go on and on but if you know anyone whose going to buy a new house in France or Spain, they are really stupid. On the net today you can easily check out what is good and what is bad - the only problem then is to find a builder that will do what you want. That and a possible hard Brexit is why we are going to go on renting, it's the only sensible thing to do.

Cavity construction walls are a joke in this day and age. British bricks soak up water hence c/w/c. Aircrete blocks are the only sensible way to go (invented in 1924) with a waterproof crepi finish. No need for plaster, size and use 1200 grade lining paper and never use vinyl/plastic paint if you want a healthy indoor environment. You will have privacy between rooms, real acoustic and thermal insulation and they are fireproof. Dense concrete blocks should have been banned decades ago. Domestic kitchens are a joke as is central heating, great big cons. Sit down and look at what the function of a kitchen is and think about when and where you need heating.

A room constructed of aircrete blocks, 10 or 15cm with a wooden floor on battens over concrete with a waterproof additive and a t&g wooden ceiling or double plasterboard ceiling, wood is preferable and you will have a superb listening environment that will not annoy others who don't want to hear your music. If you can park a car and pull down a garage and use these materials - your golden.
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  #19  
Old 26th January 2018, 09:43 PM
bob orbell bob orbell is offline
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Default Re: Another set of secondhand speakers

Wooden floor, you must be joking, I have lived in 4 houses, three with solid concrete and one with tong and groove wood, the latter was bloody awful, give me a solid concrete floor any day. BOB
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  #20  
Old 26th January 2018, 11:00 PM
Chris Chris is offline
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Default Re: Another set of secondhand speakers

I've just put in 100mm of insulation under concrete slab, good to have south facing windows and patio to heat up the slab during the Winter months.

Chris.
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