ANOTHER - Impulse buy -- Magnavox 8802
- Thread starter S Swanson
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I thought that was the answer - but only from a layman's perspective - And Did- not want to encourage debate - that was contentious in anyway --- - What was that cop show ? where the guy was always saying -Just the facts Mam ! -- Passive aggressive I suppose === But kind -of funny.
So it matters ? or NOT?? what the original amp was tube wise - as a example a transformer from a 6bq5 set up as opposed to OP transformers from a 7591 based Pull ---as long as there - the same brand Scott - fisher - heath - or the like ? with the same impedance ?
Each and every transformer will have unique characteristics that must be designed around and tuned for regardless of brand, that matter more than the exact plate to plate impedance- yes- anything in the 8K-10K will generally work fine for either the 6BQ5 or 6V6GT. Dave experimented with the Z-565 and tried to get Ultra Linear to work well (on the 8800 with 6V6GT), and ultimately abandoned that feature. Usually transformer choice will be driven more by what you have on hand, what is available, or can afford, or what will fit on your chassis.
'what fits' is a consideration not to be underestimated. I have a console pull with not-great transformers, but they fit and they were cheap. I could find something else that fits and probably suck a little less but nothing I put there is going to be truly great. The chassis just doesn't have space for anything bigger and that will always limit bass performance. Whats on there is better than what it came with though, very incorrect loading on the stock stuff which made performance into an 8 ohm load really dismal.
I still see - Cheer leaders for ultra linear - And of course am interested --
But again as a Layman any meaningful comment will have to wait --- That said - I would like to get some bang for the buck - and unless I have Misjudged there seems to be more to be had from the -vintage stuff then new at a comparable price point -however - it is still hard to KNOW - sure I could guess - but - I would rather - PUNT- to others who have measured these things - or KNOW there reputation -- I see Scott Dynaco Heathkit and others as Recommended ???? are there Sleepers among the offerings - I really don't know - As a example I was looking at some 3647w LUX transformers - interesting - Good Perhaps ? a vintage Sansui h15-8 seems like that may be interesting - where all these stand relative to each is TO ME a complete mystery - But there is a difference !!!
KINDA A SPLURGE - The Sansui H15-8 ( 15 w- and 8 K)looked to interesting -built in the late 50s by Hashimoto -So its on the way ! - could not help myself -
I think @ 15watts they will be on the edge power wise - my hope is the older transformer manufactures were a bit more honest - spec wise - compared to the current crop --of guys - in any event it should be interesting
Should be fine, normally where you see transformers hitting their power handling limits first is they saturate at the bottom end and have weird distortion in the very low bass region. Maybe its only clean to 30hz at full power vs 20hz. Not the end of the world. With the voltage available in this i don't think it will break 15w anyway
The transformers are still made -- I was able to find a website with the Sansui history a d links to the Hashimoto models - Is this helpful ? - from a design perspective
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Pretty impressive specs. (Should be for the price! )
Maximum rated power is at 50Hz, a challenging frequency where many transformers roll off. The 15W is likely based upon performance, not "meltdown", so it should be spectacular even with the 6V6GT push-pull cranked. (by the way the typical 6V6GT push pull is considered a 10W at the speaker circuit.)
The primary magnetizing inductance, combined with the spectacularly flat frequency response chart at the low end means this should be "more than capable" of putting out really solid bass. They list that the magnetizing inductance is still 85H for a 3.5mA imbalance between the two bias currents, but since you have put in DC balance, this can be zero'd out so you will always be able to ensure the maximum bass performance.
Maximum rated power is at 50Hz, a challenging frequency where many transformers roll off. The 15W is likely based upon performance, not "meltdown", so it should be spectacular even with the 6V6GT push-pull cranked. (by the way the typical 6V6GT push pull is considered a 10W at the speaker circuit.)
The primary magnetizing inductance, combined with the spectacularly flat frequency response chart at the low end means this should be "more than capable" of putting out really solid bass. They list that the magnetizing inductance is still 85H for a 3.5mA imbalance between the two bias currents, but since you have put in DC balance, this can be zero'd out so you will always be able to ensure the maximum bass performance.
Price was a Factor - but used they were very reasonable - got the pair for -- 138 plus shipping and duties --whatever that is --- ( UNREASONABLE @ 68 but oh well )--- I always look for combined shipping - in Hawaii Punishment IS coming --- So I ready myself for shipping sticker shock - Anything from Japan is expensive to Ship----
I think you read my mind about a custom chassis - I have time in the stock 8802 ,, but could improve the look if not the performance -- Thinking ----
My thinking exactly -- At one time I was looking at some iwistao (?) - Chinese transformers -- with questionable performance --- Just suspicion Here -- Steven Lancaster -- U Tube guy - confirmed my worries though -- Not exactly Good Real world performance --
Not the Point though - - for our topic Fore You are correct for even them the 200$ mark I was there --- I looked elseware - and pricing was Eye Shocking high - for the Praised ones --That is --
Back to used for me --
I meant for something not-Chinese but yeah I guess the China ones are pretty cheap. I was thinking Edcor, MPS, Hammond, etc. Looks like a 15 watt transformer in the right impedance range from Edcor are about 140 each, others I'd guess are in a similar price range so ~300 for a pair. Getting a pair of Hashimoto for 200 is a good deal.
I hope so - I read- somewhere ( DAVE G -said ) that Even the USA stuff Has dubious performance -
I will attempt a ( partial quote ) - It went something like - the Hammond's -- Edcor's and other current production stuff was Little better than Transformers meant for guitar amplification ( In TESTED performance ) His point was to compare and contrast The Vintage stuff with current Production - He did like the appearance ; though Pretty wires, and all ---But to be fair any manufacturer will have a Dog sometimes ---
It seems Like work (akin to) separating the wheat from the Chaff - Real WORK-- SO in behalf of those who don't have those skills - Thank you - To the more skilled among us willing to share
yeah they are hit and miss for sure. Never messed with Hammond stuff so no comment there but the Edcors on my 9300 do not seem to perform as well as the Dynaco repops. I've used one pair of MPS transformers and while I got good results, the Eico ST70 transformers on my similar-ish 6L6 family amp are definitely better. I've got some other classic iron around to build with so I probably won't be deeply exploring the world of modern transformers any time soon.
Speaking of the VINTAGE units - A guy Had on the BAY -a Scott Transformer that was described as A 4Kx2 (TRA 8-5-2 ) That seems like a ODD description - Is that a 8K - and Just a weird way describing it ?
