tubelab.com said:
Granted it was only on the bench but I had encouraging success using the 4 ohm taps and treating it like a 10K:8 OPT with a triode-connected 813. It has enough iron. The top end was ~ 1dB down at 20 kHz with no evidence of the dreaded notch.
Hi Tubelab,
Besides mondo amounts of NFB? A swamping resistor that gobbles 1/2 the power
Cheers!
tubelab.com said:
Besides mondo amounts of NFB? A swamping resistor that gobbles 1/2 the power
Cheers!
I remember you stating this in a Hammond bashing thread a while ago, so I tried it. I guess my transformers are (as many of these) slightly different from yours, and different from each other. First off I confirmed that one of mine had mis marked primaries. I don't remember the details (I am currently 1100 miles from home) but I think the plate and UL wires were swapped. One of them lost most of the HF when the two secondaries were paralleled for 4 ohm operation. It worked the best when all of the windings were wired in series. The other worked best at 4 ohms. I marked this info on the transformer boxes, but I can't remember the exact details now.
The transformers have been sitting unused since I got them, their only use has been some temporary duty as chokes. I also have a pair of 1628SEA's that are in a Simple SE. They work much better, and sound pretty good. In fact that amp has some serious wall shaking bass on the 15 inch OB Silver Iris speakers. I was set to build the amp into a permanent enclosure until a chance experiment with the pair of Edcor CXSE's that I have. The Edcors booted the Hammonds out of the amp for about a year, but now the Hammonds are back and I plan to make a VT225 - 307A Tubelab SE with the Edcors. That combination just sounds too good.
I'm not even sure that would work. The big Hammonds are the most inefficient of all the transformers that I tested. The cheap Edcors beat them by almost a watt on a 6 watt amp.
Hi tubelab, rdf and Geek,
The last time I attended a trade show, Hammond was there. They even had members from the Hammond family present. I think I will ask them about these problems, eye to eye.
I can't promise anything, but an effort will be made.
-Chris
The last time I attended a trade show, Hammond was there. They even had members from the Hammond family present. I think I will ask them about these problems, eye to eye.
I can't promise anything, but an effort will be made.
-Chris
From the symptoms of buzzing, running hot, high ext. mag. fields, and over voltaged outputs, along with the very high price of copper lately, I'll make an easy guess as to the problem:
They obviously have reduced the number of turns of wire to save copper, but have kept the turns ratio the same.
With fewer turns, the B field is banging into saturation, causing field to spill outside plus the humming and buzzing. The fewer turns have caused the copper loss to go down at rated current, so the internal voltage drop in the xfmr. has decreased at load. Since transformers are wound to have a higher no load voltage to make up for the loss (ie, a turns ratio higher than naively expected), this now leaves the resulting output voltage at load higher than before.
Question now is, have they done the same to the 300 series too?
They obviously have reduced the number of turns of wire to save copper, but have kept the turns ratio the same.
With fewer turns, the B field is banging into saturation, causing field to spill outside plus the humming and buzzing. The fewer turns have caused the copper loss to go down at rated current, so the internal voltage drop in the xfmr. has decreased at load. Since transformers are wound to have a higher no load voltage to make up for the loss (ie, a turns ratio higher than naively expected), this now leaves the resulting output voltage at load higher than before.
Question now is, have they done the same to the 300 series too?
have any of you gentlemen tried Mercury Magnetics in california ? They specialize in tube transformers and they seem to have some very killer upgrades for many old tube guitar and bass amplifiers as well as many off the shelf tube transformers. I recently repaired and old sun amp for a friends and the new transformer absolutely rocks.
http://www.mercurymagnetics.com/
I to have had problems with Hammond transformers being out of spec.
http://www.mercurymagnetics.com/
I to have had problems with Hammond transformers being out of spec.
Holy cow dude, I've been reading this forum for about a half hour now, and am nowhere near as knowledgeable as any of you, but I would say you have a very good explanation!
Now, my question is: will Hammond admit to this?
As a Canadian, I demand the truth! please?
as for the Allied transformers being made by Hammond, and not behaving badly, well maybe they are older stock?
Heck they're probably not even made in Canada anyway...
One thing they'll never be able to make in China that we make here dammit, is Maple syrup. I guarantee that.
Now, my question is: will Hammond admit to this?
As a Canadian, I demand the truth! please?
as for the Allied transformers being made by Hammond, and not behaving badly, well maybe they are older stock?
Heck they're probably not even made in Canada anyway...
One thing they'll never be able to make in China that we make here dammit, is Maple syrup. I guarantee that.
gain-wire said:
Check your dollar store - maple syrup (unlabled knockoff I'm sure) with "PRODUCT OF CHINA" on it
I don't see why not. I've had some frank conversations with them on the phone in the past.
Cheers!
gain-wire said:
Way off topic but I just glanced at your profile. By 'The Upper Crust' do you mean the band?
what?
the Dollar store has "chinese" maple syrup? coming from what, japanese midget maples?
Hey we don't make, I don't know... rice in Canada! (as much as I love it). why should they pretend to make maple syrup,
this has gone way off track but it's buggin me as hell...
over and out.
oh yeah, Hammond get your stuff together, on behalf of the DIYaudio community!
the Dollar store has "chinese" maple syrup? coming from what, japanese midget maples?
Hey we don't make, I don't know... rice in Canada! (as much as I love it). why should they pretend to make maple syrup,
this has gone way off track but it's buggin me as hell...
over and out.
oh yeah, Hammond get your stuff together, on behalf of the DIYaudio community!
Yes THE UPPER CRUST RUUUUULLLLES!!!
finally someone who knows a good band1
(I can only hope)
they've put back the Balls in Rock! (and a serious amount of tongue-in cheek too!) www.theuppercrust.org
finally someone who knows a good band1
(I can only hope)
they've put back the Balls in Rock! (and a serious amount of tongue-in cheek too!) www.theuppercrust.org
Since the topic is doomed... 😀
Wild rice is wildly popular and guess what? It don't grow in Asia 😉
Saskatchewan is the worlds largest producer.
The Chinese maple syrup is maple flavoured AFAIK, but because many dollar stores buy at auctions from outside Canada where labling and ingredient disclosure requirements are non existant.. *shrug*
Cheers!
gain-wire said:
Wild rice is wildly popular and guess what? It don't grow in Asia 😉
Saskatchewan is the worlds largest producer.
The Chinese maple syrup is maple flavoured AFAIK, but because many dollar stores buy at auctions from outside Canada where labling and ingredient disclosure requirements are non existant.. *shrug*
Cheers!
gain-wire said:
Let them eat rock. 😀
Do you know their precursor versions, The Satanics and before that The Titanics? Double 🙂.
Kramerguy said:
Nice find.... they certainly specialize in Guitar amp upgrades. They don't seem to offer anything in a power transformer for under $95 and you would have to be familiar with the original amp design to pick something you could adapt. I also noticed that Hammond now make a potted version of some 300 series, but they are very expensive.
http://www.hammondmfg.com/300Pseries.htm
I guess now is the logical time for me to put a shameless plug in for Hashimoto. To date I've not had a peep of trouble with them. They are truly top-notch across the board and offer a wide range of iron specifically aimed at audio. They're not cheap but they are virtually flawless.
Regards, KM
Hey rdf, at the risk of being a parasite to this post, no I don't know about the previous groups like the Satanics and the Titanics, but I somehow doubt that it would be as good.
I tried emailing you through diyaudio but it said that you were unreachable. I wanted to email to avoid plaguing this topic with an off-topic comment. although I do have one more:
Saskatchewan produces rice?
like they say in Quebec, I'll go to bed less dumber tonight!
I had no idea...
I'm outta here
I tried emailing you through diyaudio but it said that you were unreachable. I wanted to email to avoid plaguing this topic with an off-topic comment. although I do have one more:
Saskatchewan produces rice?
like they say in Quebec, I'll go to bed less dumber tonight!
I had no idea...
I'm outta here
Hi kmaier,
Now, back on topic .........
In the mean time, use iron that works and ask for an exchange for transformers that are defective. When the accounting department sees warranty costs going up, they might smarten up and back off. Accountants are normally terrible business people.
Hi gain-wire,
On the plus side, people at Hammond Manufacturing have always been very approachable. Understand too that audio and hobbyist markets do not exist really. The dollars are too small to worry about in any big way. If you want a better product, then you must be prepared to pay for it. Remember the cost of labour in other parts of the world are a small fraction of what it costs here.
I have a feeling that the less expensive transformers are not made in their plant, but rather a small outfit here (non-union), or off shore.
-Chris
Now, back on topic .........
No problem, but the next trade show will probably be in September. Still, this seems to be a concern for both Hammond and their customers.
In the mean time, use iron that works and ask for an exchange for transformers that are defective. When the accounting department sees warranty costs going up, they might smarten up and back off. Accountants are normally terrible business people.
Hi gain-wire,
Why so indignant? It's a world economy out there, and most consumers have voted with their dollars. Cheap is in, because of all of us.
On the plus side, people at Hammond Manufacturing have always been very approachable. Understand too that audio and hobbyist markets do not exist really. The dollars are too small to worry about in any big way. If you want a better product, then you must be prepared to pay for it. Remember the cost of labour in other parts of the world are a small fraction of what it costs here.
I have a feeling that the less expensive transformers are not made in their plant, but rather a small outfit here (non-union), or off shore.
-Chris
Hi anatech,
I generally agree with everything you said, as I am aware that it is the competion's lower prices that drive us (speaking of locally, as in USA and Canada) to make cheaper products, and since we can't lower our wages(labour costs you said), then it obviously has to be made elsewhere. But still, does that have to bring down quality control?
If I remeber well inconsistency was the main concern at the beginning of the topic. doesn't that relate more to quality control than overall design and assembly? Or maybe the topic switched to general overvoltage problems, because so many other diy'ers complained about the same problem.
In any case I don't wish to really bash Hammond (I support them because they are Canadian and am satisfied with what I used) but I want to see if my impressions are well-founded, by questionning. It might be that I do it in a way seems to bash them but I donT' want to.
On the topic of line voltage (out of your wall) mine here in has always been 125V, for at least 12 years.
ps: I know this might seem like no help at all to some, but you might want to buy an old broken tube oscilloscope or HP test oscillator, they have really nice power transformers. I know I got three nice 8 pound irons form old "candidates"! the tektronix stuff has like three 6.3V outputs, two HV outputs and one 1200V output, that outta be enough.
cheers
I generally agree with everything you said, as I am aware that it is the competion's lower prices that drive us (speaking of locally, as in USA and Canada) to make cheaper products, and since we can't lower our wages(labour costs you said), then it obviously has to be made elsewhere. But still, does that have to bring down quality control?
If I remeber well inconsistency was the main concern at the beginning of the topic. doesn't that relate more to quality control than overall design and assembly? Or maybe the topic switched to general overvoltage problems, because so many other diy'ers complained about the same problem.
In any case I don't wish to really bash Hammond (I support them because they are Canadian and am satisfied with what I used) but I want to see if my impressions are well-founded, by questionning. It might be that I do it in a way seems to bash them but I donT' want to.
On the topic of line voltage (out of your wall) mine here in has always been 125V, for at least 12 years.
ps: I know this might seem like no help at all to some, but you might want to buy an old broken tube oscilloscope or HP test oscillator, they have really nice power transformers. I know I got three nice 8 pound irons form old "candidates"! the tektronix stuff has like three 6.3V outputs, two HV outputs and one 1200V output, that outta be enough.
cheers
Hi gain-wire,
Please don't destroy old test equipment!!! I enjoy restoring old radios, old stereo gear and older HP test equipment. Those older HP test oscillators work extremely well. The 65x series are my favorite. Even the newer 3336 and 3325 units are well worth fixing and using. There performance completely blows away the new Asian stuff. Mind you, the DDS stuff is looking very interesting.
-Chris
Oh no!
Please don't destroy old test equipment!!! I enjoy restoring old radios, old stereo gear and older HP test equipment. Those older HP test oscillators work extremely well. The 65x series are my favorite. Even the newer 3336 and 3325 units are well worth fixing and using. There performance completely blows away the new Asian stuff. Mind you, the DDS stuff is looking very interesting.
Yes. Same here and I lived in two different cities in this time frame. Three different service shop locations also ran high.
-Chris
woops! yeah I forgot to tell you I don't destroy old test equipment. As a metter of fact, I am exactly like you : I love restore old electronic stuff. Those transformers I described were from a friend who's hobbies included buying (or obtaining) old electronic stuff and dismantling it.
Are you ready for the list?
-Heathkit Mono power amplifier and preamplifier (late fifties era) I still have the pc boards with soem originalparts and the dynaco tubes. anyone interested?
-HP test oscillator (the smaller tall version of the 200D I think)
-Tektronix oscilloscope (I don't know what model)
-Old WW2 communication radios in cdn army barrels.
-Kennedy 9 track open reel tape storgae units. Heavy aluminum frames.
Luckily he gave me:
-Heathkit SB-301 in working condition
-Lafayette tube integrated amplifier
-Pioneer CT-f750 cassette deck
-Bogen challenger amplifier (was on Ebay two months ago)
-tek 543a and 564.
MERCI ALAIN!
I'm telling you this guy's basement is packed with electronics and HAM radio stuff.
I have to call him up, see what he is up to.
So no I don't take apart stuff unlees like the scope tube would be damaged or the variable capacitor plates would be bent, or you know something like that.
Are you ready for the list?
-Heathkit Mono power amplifier and preamplifier (late fifties era) I still have the pc boards with soem originalparts and the dynaco tubes. anyone interested?
-HP test oscillator (the smaller tall version of the 200D I think)
-Tektronix oscilloscope (I don't know what model)
-Old WW2 communication radios in cdn army barrels.
-Kennedy 9 track open reel tape storgae units. Heavy aluminum frames.
Luckily he gave me:
-Heathkit SB-301 in working condition
-Lafayette tube integrated amplifier
-Pioneer CT-f750 cassette deck
-Bogen challenger amplifier (was on Ebay two months ago)
-tek 543a and 564.
MERCI ALAIN!
I'm telling you this guy's basement is packed with electronics and HAM radio stuff.
I have to call him up, see what he is up to.
So no I don't take apart stuff unlees like the scope tube would be damaged or the variable capacitor plates would be bent, or you know something like that.